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AbilitiesWML

2025-11-23T10:02:20Z

Newfrenchy83: /* Common keys and tags for specials with a value */

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_opponent]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_opponent]''', while the student can be filtered with '''[filter_student]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* '''[defense]''' {{DevFeature1.19|16}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' .
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''unique_id''': {{DevFeature1.19|17}} A unique identifier for this ability, used for the registry under [[UnitsWML#.5Babilities.5D|[units][abilities]]] or [[UnitsWML#.5Bweapon_specials.5D|[units][weapon_specials]]]. If not defined, falls back to '''id'''. Used to add this ability via '''abilities_list''' key in '''[unit_type]''' or '''[effect]apply_to=new_ability'''. Similarly for weapon specials ('''[unit_type][attack]specials_list''', or via [[EffectWML]]).
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
** '''radius''': {{DevFeature1.19|13}} set to 1 by default, it determines the range within which units can be affected beyond immediately adjacent units, if the value is equal to 'full-map', the area is the entire map.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate. {{DevFeature1.19|18}} '''filter_adjacent''' is deprecated and will likely be removed in version 1.21, since a version already exists in the [[StandardUnitFilter]].
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location]. {{DevFeature1.19|18}} '''filter_adjacent_location''' is deprecated and will likely be removed in version 1.21, since a version already exists in the [[StandardUnitFilter]].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this ability appears in. Note that such events get included when a unit with this ability first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for abilities with a value ===

The '''[leadership]''', '''[heals]''', '''[regenerate]''',and '''[illuminates]''' abilities take values that specify how those abilities modify their respective base values.

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''priority''': {{DevFeature1.19|19}} This attribute allows a higher-priority ability to use as its base the value returned by a lower-priority ability of the same type. Default: 0.
* '''cumulative''': if set to 'yes', the [leadership] value will be added to another [leadership] value= same if have same id=, for other abilities, the highest value between value= or base_value will be choosen.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[heals]'' ability ===
* '''value''': the amount healed.
* Use common keys and tags for abilities with a value.

=== Extra keys used by the ''[regenerate]'' ability ===
* '''value''': the amount healed.
* Use common keys and tags for abilities with a value

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* Use common keys and tags for abilities with a value
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys and tags used by the ''[defense]'' ability ===
* '''value''': set defense to this value. Warning, the chance to be hit decrease when value of ability increase.
* Use common keys and tags for abilities with a value

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* Use common keys and tags for abilities with a value
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect. If you use [affect_adjacent] the terrain under and adjacent to adjacent unit will be changed.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* Use Common keys and tags for abilities with a value
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.
* '''radius''': {{DevFeature1.19|15}} defines the radius of the ability, by default only the terrain the user is on and adjacent hexes are affected, but this can now be extended to a radius defined by '''radius''' ; if '''radius'''=all_map then the whole map will be affected.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected.
* '''[filter_adjacent_student]''': {{DevFeature1.19|10}} if an adjacent unit to student does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_student]. The variables $this_unit and $other_unit both work as you'd expect. Multiple [filter_adjacent_student] can be provided, all of which must pass for the ability to activate.
** '''radius''': {{DevFeature1.19|13}} determines the distance of units that can be filtered and not just adjacent units, '''radius''' is set to 1 by default. {{DevFeature1.19|18}} '''[filter_adjacent_student]''' is removed because having multiple shorthands requires giving them specific names for abilities used as weapons, and it's even simpler to use the [[StandardUnitFilter]].
* '''[filter_adjacent_student_location]''': {{DevFeature1.19|10}} like [filter_adjacent_student], but filters on locations instead of units. This is a shorthand for [filter_student][filter_location][filter_adjacent_location]. {{DevFeature1.19|18}} '''[filter_adjacent_student_location]''' is removed because having multiple shorthands requires giving them specific names for abilities used as weapons, and it's even simpler to use the [[StandardUnitFilter]].
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
** '''description_affected''': {{DevFeature1.17|13}} becomes the '''description''' of the weapon special, without changing the '''description''' of the ability
** '''name_affected''': {{DevFeature1.17|13}} becomes the '''name''' of the weapon special, without changing the '''name''' of the ability
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[defense]''' {{DevFeature1.19|15}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' {{DevFeature1.19|16}} [defense] is no longer a weapon special but an ability.
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker '''value''' percentage of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50 by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate. {{DevFeature1.19|18}} '''filter_adjacent''' is deprecated and will likely be removed in version 1.21, since a version already exists in the [[StandardUnitFilter]] and ''count'' is no longer required.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location]. {{DevFeature1.19|18}} '''filter_adjacent_location''' is deprecated and will likely be removed in version 1.21, since a version already exists in the [[StandardUnitFilter]].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this weapon special appears in. Note that such events get included when a unit with this weapon special first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''priority''': {{DevFeature1.19|19}} This attribute allows a higher-priority special to use as its base the value returned by a lower-priority special of the same type. Default: 0.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special ===

{{DevFeature1.17|23}}

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

AbilitiesWML

2025-11-23T10:01:18Z

Newfrenchy83: /* Common keys and tags for abilities with a value */

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_opponent]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_opponent]''', while the student can be filtered with '''[filter_student]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* '''[defense]''' {{DevFeature1.19|16}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' .
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''unique_id''': {{DevFeature1.19|17}} A unique identifier for this ability, used for the registry under [[UnitsWML#.5Babilities.5D|[units][abilities]]] or [[UnitsWML#.5Bweapon_specials.5D|[units][weapon_specials]]]. If not defined, falls back to '''id'''. Used to add this ability via '''abilities_list''' key in '''[unit_type]''' or '''[effect]apply_to=new_ability'''. Similarly for weapon specials ('''[unit_type][attack]specials_list''', or via [[EffectWML]]).
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
** '''radius''': {{DevFeature1.19|13}} set to 1 by default, it determines the range within which units can be affected beyond immediately adjacent units, if the value is equal to 'full-map', the area is the entire map.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate. {{DevFeature1.19|18}} '''filter_adjacent''' is deprecated and will likely be removed in version 1.21, since a version already exists in the [[StandardUnitFilter]].
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location]. {{DevFeature1.19|18}} '''filter_adjacent_location''' is deprecated and will likely be removed in version 1.21, since a version already exists in the [[StandardUnitFilter]].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this ability appears in. Note that such events get included when a unit with this ability first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for abilities with a value ===

The '''[leadership]''', '''[heals]''', '''[regenerate]''',and '''[illuminates]''' abilities take values that specify how those abilities modify their respective base values.

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''priority''': {{DevFeature1.19|19}} This attribute allows a higher-priority ability to use as its base the value returned by a lower-priority ability of the same type. Default: 0.
* '''cumulative''': if set to 'yes', the [leadership] value will be added to another [leadership] value= same if have same id=, for other abilities, the highest value between value= or base_value will be choosen.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[heals]'' ability ===
* '''value''': the amount healed.
* Use common keys and tags for abilities with a value.

=== Extra keys used by the ''[regenerate]'' ability ===
* '''value''': the amount healed.
* Use common keys and tags for abilities with a value

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* Use common keys and tags for abilities with a value
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys and tags used by the ''[defense]'' ability ===
* '''value''': set defense to this value. Warning, the chance to be hit decrease when value of ability increase.
* Use common keys and tags for abilities with a value

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* Use common keys and tags for abilities with a value
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect. If you use [affect_adjacent] the terrain under and adjacent to adjacent unit will be changed.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* Use Common keys and tags for abilities with a value
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.
* '''radius''': {{DevFeature1.19|15}} defines the radius of the ability, by default only the terrain the user is on and adjacent hexes are affected, but this can now be extended to a radius defined by '''radius''' ; if '''radius'''=all_map then the whole map will be affected.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected.
* '''[filter_adjacent_student]''': {{DevFeature1.19|10}} if an adjacent unit to student does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_student]. The variables $this_unit and $other_unit both work as you'd expect. Multiple [filter_adjacent_student] can be provided, all of which must pass for the ability to activate.
** '''radius''': {{DevFeature1.19|13}} determines the distance of units that can be filtered and not just adjacent units, '''radius''' is set to 1 by default. {{DevFeature1.19|18}} '''[filter_adjacent_student]''' is removed because having multiple shorthands requires giving them specific names for abilities used as weapons, and it's even simpler to use the [[StandardUnitFilter]].
* '''[filter_adjacent_student_location]''': {{DevFeature1.19|10}} like [filter_adjacent_student], but filters on locations instead of units. This is a shorthand for [filter_student][filter_location][filter_adjacent_location]. {{DevFeature1.19|18}} '''[filter_adjacent_student_location]''' is removed because having multiple shorthands requires giving them specific names for abilities used as weapons, and it's even simpler to use the [[StandardUnitFilter]].
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
** '''description_affected''': {{DevFeature1.17|13}} becomes the '''description''' of the weapon special, without changing the '''description''' of the ability
** '''name_affected''': {{DevFeature1.17|13}} becomes the '''name''' of the weapon special, without changing the '''name''' of the ability
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[defense]''' {{DevFeature1.19|15}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' {{DevFeature1.19|16}} [defense] is no longer a weapon special but an ability.
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker '''value''' percentage of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50 by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate. {{DevFeature1.19|18}} '''filter_adjacent''' is deprecated and will likely be removed in version 1.21, since a version already exists in the [[StandardUnitFilter]] and ''count'' is no longer required.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location]. {{DevFeature1.19|18}} '''filter_adjacent_location''' is deprecated and will likely be removed in version 1.21, since a version already exists in the [[StandardUnitFilter]].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this weapon special appears in. Note that such events get included when a unit with this weapon special first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special ===

{{DevFeature1.17|23}}

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

StandardUnitFilter

2025-11-09T10:24:03Z

Newfrenchy83:

{{WML Tags}}

From [[FilterWML]], this is the standard way of filtering units.

When a unit filter is applied to a map, first it applies to all units on the field,
based on their coordinates.
Next it applies to units in the recall list.
This is important to remember as it means, for example,
that the tag '''[kill]''' can be used to kill units in the recall list.

You can access the filtered unit within the filter as the ''$this_unit'' variable, see [[SingleUnitWML]] for the possible content of these variables

The term [[StandardUnitFilter]] means that the set of such keys and tags (see below) can appear at that point. Often a [[StandardUnitFilter]] needs to be included in a [filter] tag. But many tags take the [[StandardUnitFilter]] directly as an argument, like [[DirectActionsWML#.5Bkill.5D|[kill]]] and [[ConditionalActionsWML#.5Bhave_unit.5D|[have_unit]]] (which each accept a few additional keys of their own). See [[Special:WhatLinksHere/StandardUnitFilter]] for tags which can contain a StandardUnitFilter.

__TOC__

The following attributes and sub-tags are allowed:

* '''id''': unit matches the given id. This is the same as ''id'' in the [unit] tag. Note that it is independent of a unit's user-visible name, which can be internationalized independent of this (see [[SingleUnitWML]]). id= can be a comma-separated list, every unit with one of these ids matches.
* '''speaker''': alias for id (no comma-separated list supported)
* '''type''': matches the unit's type name (can be a list of types)
* '''type_adv_tree''': {{DevFeature1.13|7}} matches the type name of the unit and all its advancements (can be a list)
* '''race''': the race of the unit type. This can be a comma-separated list; the unit's race must match one of the given races. Mainline races are listed in data/core/units.cfg 
* '''variation''': the unit type variation id (can be a list of variation ids)
* '''has_variation''': matches if the unit type for the unit defines at least one of the variation ids provided as a comma-separated list
* '''upkeep''': {{DevFeature1.15|3}} The upkeep of the unit. Can be either a non-negative number or one of the special values ''loyal'', ''free'', ''full''. Note that while ''loyal'' and ''free'' are synonymous with an upkeep of 0, the value ''full'' is not synonymous with any single numeric value – it is equivalent to <code>$this_unit.level</code>.
* '''ability''': unit has an ability with the given id; see [[AbilitiesWML]]. This can be a comma-separated list. The unit must have at least one of the specified abilities.
* '''ability_type''': {{DevFeature1.13|7}} unit has an ability with the given type (tag name) - eg, ''ability_type=heals'' will match a unit with any healing ability.
* '''ability_type_active''': {{DevFeature1.13|8}} unit has an ''active'' ability with the given type (tag name).
* '''ability_id_active''': {{DevFeature1.15|13}} unit has an ''active'' ability with the given id; see [[AbilitiesWML]]
* '''trait''': {{DevFeature1.13|8}} This can be a comma-separated list. The unit must have at least one of the specified traits.
* '''status''': {{DevFeature1.13|0}} matches if the unit has the specified status active. This can be a comma-separated list, in which case the unit will match as long as it has one of the listed statuses active (note: possible statuses are listed on the [[SingleUnitWML]] page).
* '''side''': the unit is on the given side (can be a list)
* '''has_weapon''': the unit has a weapon with the given name {{DevFeature1.13|5}} Now deprecated
* {{anchor|has_attack|'''[has_attack]'''}}: {{DevFeature1.13|5}} the unit has a weapon matching the [[StandardWeaponFilter]]. If this is present, '''has_weapon''' is ignored.
* '''canrecruit''': yes if the unit can recruit (i.e. is a leader)
* '''gender''': female if the unit is female rather than the default of male
* '''role''': the unit has been assigned the given role; see '''[role]''', [[InternalActionsWML]]
* '''level''': the level of the unit (this can be a comma-separated list).
* '''defense''': current defense of the unit on current tile (chance to hit %, like in movement type definitions)
* '''movement_cost''': current movement cost of the unit on current tile. Can be a number, range, or comma separated range.
* '''x,y''': the position of the unit. Note: As a special case '''x,y=recall,recall''' matches units on the recall list. Note that the similar '''search_recall_list=yes''' key is only available as part of the '''[have_unit]''' condition tag, and is not otherwise considered part of a StandardUnitFilter.
* '''find_in''': name of an array or container variable; if present, the unit will not match unless a unit with the same '''id''' is already stored in the variable
* {{anchor|filter_vision|'''[filter_vision]'''}}: this tests whether or not the unit is currently visible
** '''visible''': yes or no, default yes. When "yes", this matches units that are not obscured by fog or shroud, and that are not hiding (via the {{tag|AbilitiesWML|hides}} ability). When "no", this matches units that are obscured by fog or shroud, or that are hiding.
** [[StandardSideFilter]] tags and keys. Filter for who may be able to see (or not see) the unit. If there is *at least one* matching side which can see the unit then the filter matches, and otherwise it fails to match.
* {{anchor|filter_wml|'''[filter_wml]'''}}: Converts the unit to WML (as if by '''[store_unit]''') and tests it against a [[FilterWML#Filtering_on_WML_data|WML filter]]. For a list of things in the WML that could be filtered on, see [[SingleUnitWML]] or open a saved game in a text editor. Note that this is slower than other methods, so if possible it's better to use other filter keys and tags; however, if the WML filter contains only a child '''[variables]''', then the unit is not converted to WML and the filter is matched only against the unit's variables (which are already WML).
* '''[and]''': an extra unit filter. Unless the unit also matches the [and] filter, then it will not count as a match. ''Note: [and],[or], and [not] filters are considered after the containing filter; they are then processed in the order encountered.''
* '''[or]''': an extra unit filter. If a unit matches the [or] filter, then it will count as a match regardless of conditions in previous filters or the containing filter.
* '''[not]''': an extra unit filter. If a unit matches the [not] filter, then that unit will not be considered a match by the containing filter.
* {{anchor|filter_adjacent|'''[filter_adjacent]'''}} with a StandardUnitFilter as argument. If present the correct number of adjacent units must match this filter.
**'''StandardUnitFilter''' tags and keys
** '''count''': a number, range, or comma separated range; default "1-6" {{DevFeature1.19|13}} '''count''' no longer has a default value since `filters adjacent` supports remote units thanks to '''radius'''.
** '''adjacent''': a comma separated list of directions; default "n,ne,se,s,sw,nw" (see [[StandardLocationFilter#Directions|notes]])
** '''is_enemy''': a boolean specifying whether the adjacent unit must be an enemy or an ally (optional)
** '''$other_unit''': {{DevFeature1.13|2}} Within [filter_adjacent], the special variable $other_unit refers to the filtered unit from the enclosing filter, while $this_unit refers (as with all StandardUnitFilters) to the unit being filtered on.
** '''radius''': {{DevFeature1.19|13}} determines the distance of units that can be filtered and not just adjacent units, '''radius''' is set to 1 by default.
* '''[filter_location]''': [[StandardLocationFilter]] - the tile that the unit is standing on matches the location filter.
*'''[filter_side]''': The currently filtered unit's side must match this [[StandardSideFilter]] for the unit to match.
**[[StandardSideFilter]] tags and keys
* '''formula''': A formula using [[Wesnoth Formula Language]]. The <tt>self</tt> variable is set to the current $this_unit, and the formula should return a boolean. If it returns 0, the filter does not match. Otherwise, the filter does match. {{DevFeature1.13|5}} If the filter has a secondary unit, the formula can access it using the <code>other</code> variable. Both the unit and the secondary unit are a '''unit object''', with keys documented [[#Wesnoth_Formula_Language|below]]. Do not surround the formula in <code>$(...)</code>, since that will erase the <tt>self</tt> variable.
* '''lua_function''': the name of a [[LuaWML|Lua]] function in the global environment that takes a unit as an argument and returns true if the given unit matches the filter. {{DevFeature1.13|5}} Non-global functions can now be used here by building a dot-separated "path". Note that this is not actually interpreted as Lua code even though it superficially resembles it, so using a Lua keyword in the path will work, for example "my_filter_functions.goto" will correctly use the function which in actual Lua code would need to be referenced as <code>my_filter_functions["goto"]</code>.
* {{anchor|filter_ability|'''[experimental_filter_ability]'''}}: {{DevFeature1.17|17}} [[StandardAbilityFilter]] matches if the unit has an ability with the given properties - eg, ''[experimental_filter_ability]affect_self=yes'' will match a unit with any ability with ''affect_self=yes''. {{DevFeature1.19|5}} [experimental_filter_ability] deprecated, use [filter_ability] instead.
* {{anchor|filter_ability_active|'''[experimental_filter_ability_active]'''}}: {{DevFeature1.17|17}} [[StandardAbilityFilter]] matches if the unit has an ''active'' ability with the given properties - eg, ''[experimental_filter_ability_active]affect_adjacent=yes'' will match a unit with any ''active'' ability with ''[affect_adjacent]''. The attributes checked are the same as for [experimental_filter_ability]. {{DevFeature1.19|5}} [experimental_filter_ability_active] deprecated, use [filter_ability] instead.
* '''[filter_ability]''': {{DevFeature1.19|5}} [[StandardAbilityFilter]] matches if the unit has anability with the given properties - eg, ''[filter_ability]affect_adjacent=yes'' will match a unit with any ability with ''[affect_adjacent]''.
** '''active''': if active=yes, matches if the unit has an ''active'' ability with the given properties, if active=no, matches if the unit has an ability with the given properties regardless of 'active' or not. '''active''' is false by default.

== [[Wesnoth Formula Language]] ==

When using the '''formula''' key, the '''self''' and (if present) '''other''' objects support the following keys:

* '''x''', '''y''', '''loc''' - the latter is a '''location object''' such as what would be returned from [[Wesnoth_Formula_Language#loc|loc()]].
* '''id'''
* '''type'''
* '''name'''
* '''usage'''
* '''canrecruit''', '''leader'''
* '''undead''' - true if the unit has the ''not_living'' status
* '''attacks''' - a list of '''[[FilterWML#Filtering_Weapons|weapon objects]]'''
* '''abilities''' - a list of the ability IDs the unit possesses
* '''hitpoints''', '''max_hitpoints'''
* '''experience''', '''max_experience'''
* '''moves''', '''max_moves'''
* '''attacks_left''', '''max_attacks'''
* '''level''', '''full''' - '''full''' refers to the unit's level to support the formula <syntaxhighlight lang=wfl inline>upkeep = full</syntaxhighlight>
* '''traits''' - a list of the trait IDs
* '''objects''' {{DevFeature1.19|0}} - a list of the objects IDs
* '''advancements_taken''' {{DevFeature1.19|0}} - a list of the advancements taken IDs
* '''traits_count''' {{DevFeature1.19|0}} - number of traits used by unit regardless of IDs
* '''objects_count''' {{DevFeature1.19|0}} - number of objects used by unit regardless of IDs
* '''advancements_taken_count''' {{DevFeature1.19|0}} - number of advancements taken used by unit regardless of IDs
* '''extra_recruit'''
* '''advances_to'''
* '''status''' - a list of active statuses
* '''side_number'''
* '''cost'''
* '''upkeep'''
* '''loyal''' - a constant 0 to support the formula <syntaxhighlight lang=wfl inline>upkeep = loyal</syntaxhighlight>
* '''hidden'''
* '''petrified''' - true if the unit has the '''petrified''' status
* '''resting'''
* '''role'''
* '''race'''
* '''gender'''
* '''variation'''
* '''zoc'''
* '''alignment'''
* '''facing'''
* '''resistance''', '''movement_cost''', '''vision_cost''', '''jamming_cost''', '''defense''' - {{DevFeature1.15|3}} Maps containing the basic movetype data. The '''defense''' and '''resistance''' maps contain the actual defense and resistance values, rather than the values specified in the WML, so you do not need to subtract them from 100.
* '''flying''' {{DevFeature1.15|3}}
* '''fearless''', '''healthy''' {{DevFeature1.19|4}}
* '''vars''' - WFL variables owned by the unit, which can be set and used by FormulaAI
* '''wml_vars''' - the WML variables stored in the unit
* '''n''', '''s''', '''ne''', '''se''', '''nw''', '''sw''', '''lawful''', '''chaotic''', '''neutral''', '''liminal''', '''male''', '''female''' - these are all defined to be the equivalent string so that, for example, you can write a formula like <syntaxhighlight lang=wfl inline>alignment = liminal and gender = female</syntaxhighlight> without needing to quote the alignment and gender strings.

== A Note about Re-Using the Same Attribute ==
You are limited to having each attribute, such as '''id''', appear once or less in a [[StandardUnitFilter]]. However, this can be worked around. If you have several specific units you want excepted from matching, use a separate [or] subfilters for each one. Also you can use [not] subfilters. For example to kill ([kill] uses the standard unit filter) all units except Gwiti Ha'atel and Tanar you can do the following:

<syntaxhighlight lang='wml'>
[kill]
[not]
id=Gwiti Ha'atel
[/not]
[not]
id=Tanar
[/not]
[/kill]
</syntaxhighlight>

And similarly if you wanted to kill both Gwiti Ha'atel and Tanar, but no one else you could do the following:

<syntaxhighlight lang='wml'>
[kill]
id=Gwiti Ha'atel
[or]
id=Tanar
[/or]
[/kill]
</syntaxhighlight>

== Tutorial ==

* [[FilterWML/Examples_-_How_to_use_Filter|How To Use Filter (with examples)]]

== See Also ==

* [[FilterWML]]
* [[ReferenceWML]]

[[Category: WML Reference]]

AbilitiesWML

2025-11-09T10:18:41Z

Newfrenchy83: /* Extra tags and keys used by weapon specials as abilities */

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_opponent]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_opponent]''', while the student can be filtered with '''[filter_student]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* '''[defense]''' {{DevFeature1.19|16}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' .
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''unique_id''': {{DevFeature1.19|17}} A unique identifier for this ability, used for the registry under [[UnitsWML#.5Babilities.5D|[units][abilities]]]. If not defined, falls back to '''id'''. Used to add this ability via '''abilities''' key in '''[unit_type]''' or '''[effect]apply_to=new_ability'''.
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
** '''radius''': {{DevFeature1.19|13}} set to 1 by default, it determines the range within which units can be affected beyond immediately adjacent units, if the value is equal to 'full-map', the area is the entire map.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate. {{DevFeature1.19|18}} '''filter_adjacent''' is deprecated and will likely be removed in version 1.21, since a version already exists in the [[StandardUnitFilter]].
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location]. {{DevFeature1.19|18}} '''filter_adjacent_location''' is deprecated and will likely be removed in version 1.21, since a version already exists in the [[StandardUnitFilter]].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this ability appears in. Note that such events get included when a unit with this ability first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for abilities with a value ===

The '''[leadership]''', '''[heals]''', '''[regenerate]''',and '''[illuminates]''' abilities take values that specify how those abilities modify their respective base values.

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', the [leadership] value will be added to another [leadership] value= same if have same id=, for other abilities, the highest value between value= or base_value will be choosen.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[heals]'' ability ===
* '''value''': the amount healed.
* Use common keys and tags for abilities with a value.

=== Extra keys used by the ''[regenerate]'' ability ===
* '''value''': the amount healed.
* Use common keys and tags for abilities with a value

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* Use common keys and tags for abilities with a value
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys and tags used by the ''[defense]'' ability ===
* '''value''': set defense to this value. Warning, the chance to be hit decrease when value of ability increase.
* Use common keys and tags for abilities with a value

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* Use common keys and tags for abilities with a value
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect. If you use [affect_adjacent] the terrain under and adjacent to adjacent unit will be changed.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* Use Common keys and tags for abilities with a value
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.
* '''radius''': {{DevFeature1.19|15}} defines the radius of the ability, by default only the terrain the user is on and adjacent hexes are affected, but this can now be extended to a radius defined by '''radius''' ; if '''radius'''=all_map then the whole map will be affected.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected.
* '''[filter_adjacent_student]''': {{DevFeature1.19|10}} if an adjacent unit to student does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_student]. The variables $this_unit and $other_unit both work as you'd expect. Multiple [filter_adjacent_student] can be provided, all of which must pass for the ability to activate.
** '''radius''': {{DevFeature1.19|13}} determines the distance of units that can be filtered and not just adjacent units, '''radius''' is set to 1 by default. {{DevFeature1.19|18}} '''[filter_adjacent_student]''' is removed because having multiple shorthands requires giving them specific names for abilities used as weapons, and it's even simpler to use the [[StandardUnitFilter]].
* '''[filter_adjacent_student_location]''': {{DevFeature1.19|10}} like [filter_adjacent_student], but filters on locations instead of units. This is a shorthand for [filter_student][filter_location][filter_adjacent_location]. {{DevFeature1.19|18}} '''[filter_adjacent_student_location]''' is removed because having multiple shorthands requires giving them specific names for abilities used as weapons, and it's even simpler to use the [[StandardUnitFilter]].
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
** '''description_affected''': {{DevFeature1.17|13}} becomes the '''description''' of the weapon special, without changing the '''description''' of the ability
** '''name_affected''': {{DevFeature1.17|13}} becomes the '''name''' of the weapon special, without changing the '''name''' of the ability
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[defense]''' {{DevFeature1.19|15}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' {{DevFeature1.19|16}} [defense] is no longer a weapon special but an ability.
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker '''value''' percentage of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50 by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate. {{DevFeature1.19|18}} '''filter_adjacent''' is deprecated and will likely be removed in version 1.21, since a version already exists in the [[StandardUnitFilter]] and ''count'' is no longer required.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location]. {{DevFeature1.19|18}} '''filter_adjacent_location''' is deprecated and will likely be removed in version 1.21, since a version already exists in the [[StandardUnitFilter]].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this weapon special appears in. Note that such events get included when a unit with this weapon special first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special ===

{{DevFeature1.17|23}}

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

AbilitiesWML

2025-11-09T10:17:32Z

Newfrenchy83: /* Extra tags and keys used by weapon specials as abilities */

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_opponent]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_opponent]''', while the student can be filtered with '''[filter_student]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* '''[defense]''' {{DevFeature1.19|16}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' .
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''unique_id''': {{DevFeature1.19|17}} A unique identifier for this ability, used for the registry under [[UnitsWML#.5Babilities.5D|[units][abilities]]]. If not defined, falls back to '''id'''. Used to add this ability via '''abilities''' key in '''[unit_type]''' or '''[effect]apply_to=new_ability'''.
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
** '''radius''': {{DevFeature1.19|13}} set to 1 by default, it determines the range within which units can be affected beyond immediately adjacent units, if the value is equal to 'full-map', the area is the entire map.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate. {{DevFeature1.19|18}} '''filter_adjacent''' is deprecated and will likely be removed in version 1.21, since a version already exists in the [[StandardUnitFilter]].
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location]. {{DevFeature1.19|18}} '''filter_adjacent_location''' is deprecated and will likely be removed in version 1.21, since a version already exists in the [[StandardUnitFilter]].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this ability appears in. Note that such events get included when a unit with this ability first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for abilities with a value ===

The '''[leadership]''', '''[heals]''', '''[regenerate]''',and '''[illuminates]''' abilities take values that specify how those abilities modify their respective base values.

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', the [leadership] value will be added to another [leadership] value= same if have same id=, for other abilities, the highest value between value= or base_value will be choosen.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[heals]'' ability ===
* '''value''': the amount healed.
* Use common keys and tags for abilities with a value.

=== Extra keys used by the ''[regenerate]'' ability ===
* '''value''': the amount healed.
* Use common keys and tags for abilities with a value

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* Use common keys and tags for abilities with a value
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys and tags used by the ''[defense]'' ability ===
* '''value''': set defense to this value. Warning, the chance to be hit decrease when value of ability increase.
* Use common keys and tags for abilities with a value

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* Use common keys and tags for abilities with a value
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect. If you use [affect_adjacent] the terrain under and adjacent to adjacent unit will be changed.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* Use Common keys and tags for abilities with a value
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.
* '''radius''': {{DevFeature1.19|15}} defines the radius of the ability, by default only the terrain the user is on and adjacent hexes are affected, but this can now be extended to a radius defined by '''radius''' ; if '''radius'''=all_map then the whole map will be affected.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected.
* '''[filter_adjacent_student]''': {{DevFeature1.19|10}} if an adjacent unit to student does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_student]. The variables $this_unit and $other_unit both work as you'd expect. Multiple [filter_adjacent_student] can be provided, all of which must pass for the ability to activate.
** '''radius''': {{DevFeature1.19|13}} determines the distance of units that can be filtered and not just adjacent units, '''radius''' is set to 1 by default. {{DevFeature1.19|18}} '''[filter_adjacent_student]''' is removed because having multiple shorthands requires giving them specific names for abilities used as weapons, and it's even simpler to use the [[StandardAbilityFilter]].
* '''[filter_adjacent_student_location]''': {{DevFeature1.19|10}} like [filter_adjacent_student], but filters on locations instead of units. This is a shorthand for [filter_student][filter_location][filter_adjacent_location]. {{DevFeature1.19|18}} '''[filter_adjacent_student_location]''' is removed because having multiple shorthands requires giving them specific names for abilities used as weapons, and it's even simpler to use the [[StandardAbilityFilter]].
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
** '''description_affected''': {{DevFeature1.17|13}} becomes the '''description''' of the weapon special, without changing the '''description''' of the ability
** '''name_affected''': {{DevFeature1.17|13}} becomes the '''name''' of the weapon special, without changing the '''name''' of the ability
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[defense]''' {{DevFeature1.19|15}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' {{DevFeature1.19|16}} [defense] is no longer a weapon special but an ability.
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker '''value''' percentage of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50 by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate. {{DevFeature1.19|18}} '''filter_adjacent''' is deprecated and will likely be removed in version 1.21, since a version already exists in the [[StandardUnitFilter]] and ''count'' is no longer required.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location]. {{DevFeature1.19|18}} '''filter_adjacent_location''' is deprecated and will likely be removed in version 1.21, since a version already exists in the [[StandardUnitFilter]].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this weapon special appears in. Note that such events get included when a unit with this weapon special first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special ===

{{DevFeature1.17|23}}

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

AbilitiesWML

2025-11-09T10:10:59Z

Newfrenchy83: /* Common keys and tags for every weapon special */

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_opponent]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_opponent]''', while the student can be filtered with '''[filter_student]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* '''[defense]''' {{DevFeature1.19|16}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' .
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''unique_id''': {{DevFeature1.19|17}} A unique identifier for this ability, used for the registry under [[UnitsWML#.5Babilities.5D|[units][abilities]]]. If not defined, falls back to '''id'''. Used to add this ability via '''abilities''' key in '''[unit_type]''' or '''[effect]apply_to=new_ability'''.
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
** '''radius''': {{DevFeature1.19|13}} set to 1 by default, it determines the range within which units can be affected beyond immediately adjacent units, if the value is equal to 'full-map', the area is the entire map.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate. {{DevFeature1.19|18}} '''filter_adjacent''' is deprecated and will likely be removed in version 1.21, since a version already exists in the [[StandardUnitFilter]].
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location]. {{DevFeature1.19|18}} '''filter_adjacent_location''' is deprecated and will likely be removed in version 1.21, since a version already exists in the [[StandardUnitFilter]].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this ability appears in. Note that such events get included when a unit with this ability first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for abilities with a value ===

The '''[leadership]''', '''[heals]''', '''[regenerate]''',and '''[illuminates]''' abilities take values that specify how those abilities modify their respective base values.

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', the [leadership] value will be added to another [leadership] value= same if have same id=, for other abilities, the highest value between value= or base_value will be choosen.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[heals]'' ability ===
* '''value''': the amount healed.
* Use common keys and tags for abilities with a value.

=== Extra keys used by the ''[regenerate]'' ability ===
* '''value''': the amount healed.
* Use common keys and tags for abilities with a value

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* Use common keys and tags for abilities with a value
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys and tags used by the ''[defense]'' ability ===
* '''value''': set defense to this value. Warning, the chance to be hit decrease when value of ability increase.
* Use common keys and tags for abilities with a value

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* Use common keys and tags for abilities with a value
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect. If you use [affect_adjacent] the terrain under and adjacent to adjacent unit will be changed.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* Use Common keys and tags for abilities with a value
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.
* '''radius''': {{DevFeature1.19|15}} defines the radius of the ability, by default only the terrain the user is on and adjacent hexes are affected, but this can now be extended to a radius defined by '''radius''' ; if '''radius'''=all_map then the whole map will be affected.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected.
* '''[filter_adjacent_student]''': {{DevFeature1.19|10}} if an adjacent unit to student does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_student]. The variables $this_unit and $other_unit both work as you'd expect. Multiple [filter_adjacent_student] can be provided, all of which must pass for the ability to activate.
** '''radius''': {{DevFeature1.19|13}} determines the distance of units that can be filtered and not just adjacent units, '''radius''' is set to 1 by default.
* '''[filter_adjacent_student_location]''': {{DevFeature1.19|10}} like [filter_adjacent_student], but filters on locations instead of units. This is a shorthand for [filter_student][filter_location][filter_adjacent_location].
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
** '''description_affected''': {{DevFeature1.17|13}} becomes the '''description''' of the weapon special, without changing the '''description''' of the ability
** '''name_affected''': {{DevFeature1.17|13}} becomes the '''name''' of the weapon special, without changing the '''name''' of the ability
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[defense]''' {{DevFeature1.19|15}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' {{DevFeature1.19|16}} [defense] is no longer a weapon special but an ability.
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker '''value''' percentage of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50 by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate. {{DevFeature1.19|18}} '''filter_adjacent''' is deprecated and will likely be removed in version 1.21, since a version already exists in the [[StandardUnitFilter]] and ''count'' is no longer required.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location]. {{DevFeature1.19|18}} '''filter_adjacent_location''' is deprecated and will likely be removed in version 1.21, since a version already exists in the [[StandardUnitFilter]].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this weapon special appears in. Note that such events get included when a unit with this weapon special first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special ===

{{DevFeature1.17|23}}

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

AbilitiesWML

2025-11-09T10:04:01Z

Newfrenchy83: /* Common keys and tags for every ability */

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_opponent]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_opponent]''', while the student can be filtered with '''[filter_student]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* '''[defense]''' {{DevFeature1.19|16}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' .
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''unique_id''': {{DevFeature1.19|17}} A unique identifier for this ability, used for the registry under [[UnitsWML#.5Babilities.5D|[units][abilities]]]. If not defined, falls back to '''id'''. Used to add this ability via '''abilities''' key in '''[unit_type]''' or '''[effect]apply_to=new_ability'''.
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
** '''radius''': {{DevFeature1.19|13}} set to 1 by default, it determines the range within which units can be affected beyond immediately adjacent units, if the value is equal to 'full-map', the area is the entire map.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate. {{DevFeature1.19|18}} '''filter_adjacent''' is deprecated and will likely be removed in version 1.21, since a version already exists in the [[StandardUnitFilter]].
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location]. {{DevFeature1.19|18}} '''filter_adjacent_location''' is deprecated and will likely be removed in version 1.21, since a version already exists in the [[StandardUnitFilter]].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this ability appears in. Note that such events get included when a unit with this ability first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for abilities with a value ===

The '''[leadership]''', '''[heals]''', '''[regenerate]''',and '''[illuminates]''' abilities take values that specify how those abilities modify their respective base values.

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', the [leadership] value will be added to another [leadership] value= same if have same id=, for other abilities, the highest value between value= or base_value will be choosen.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[heals]'' ability ===
* '''value''': the amount healed.
* Use common keys and tags for abilities with a value.

=== Extra keys used by the ''[regenerate]'' ability ===
* '''value''': the amount healed.
* Use common keys and tags for abilities with a value

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* Use common keys and tags for abilities with a value
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys and tags used by the ''[defense]'' ability ===
* '''value''': set defense to this value. Warning, the chance to be hit decrease when value of ability increase.
* Use common keys and tags for abilities with a value

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* Use common keys and tags for abilities with a value
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect. If you use [affect_adjacent] the terrain under and adjacent to adjacent unit will be changed.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* Use Common keys and tags for abilities with a value
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.
* '''radius''': {{DevFeature1.19|15}} defines the radius of the ability, by default only the terrain the user is on and adjacent hexes are affected, but this can now be extended to a radius defined by '''radius''' ; if '''radius'''=all_map then the whole map will be affected.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected.
* '''[filter_adjacent_student]''': {{DevFeature1.19|10}} if an adjacent unit to student does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_student]. The variables $this_unit and $other_unit both work as you'd expect. Multiple [filter_adjacent_student] can be provided, all of which must pass for the ability to activate.
** '''radius''': {{DevFeature1.19|13}} determines the distance of units that can be filtered and not just adjacent units, '''radius''' is set to 1 by default.
* '''[filter_adjacent_student_location]''': {{DevFeature1.19|10}} like [filter_adjacent_student], but filters on locations instead of units. This is a shorthand for [filter_student][filter_location][filter_adjacent_location].
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
** '''description_affected''': {{DevFeature1.17|13}} becomes the '''description''' of the weapon special, without changing the '''description''' of the ability
** '''name_affected''': {{DevFeature1.17|13}} becomes the '''name''' of the weapon special, without changing the '''name''' of the ability
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[defense]''' {{DevFeature1.19|15}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' {{DevFeature1.19|16}} [defense] is no longer a weapon special but an ability.
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker '''value''' percentage of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50 by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this weapon special appears in. Note that such events get included when a unit with this weapon special first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special ===

{{DevFeature1.17|23}}

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

AbilitiesWML

2025-10-26T16:49:09Z

Newfrenchy83:

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_opponent]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_opponent]''', while the student can be filtered with '''[filter_student]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* '''[defense]''' {{DevFeature1.19|16}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' .
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
** '''radius''': {{DevFeature1.19|13}} set to 1 by default, it determines the range within which units can be affected beyond immediately adjacent units, if the value is equal to 'full-map', the area is the entire map.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this ability appears in. Note that such events get included when a unit with this ability first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for abilities with a value ===

The '''[leasership]''', '''[heals]''', '''[regenerate]''',and '''[illuminates]''' abilities take values that specify how those abilities modify their respective base values.

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', the [leadership] value will be added to another [leadership] value= same if have same id=, for other abilities, the highest value between value= or base_value will be choosen.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[heals]'' ability ===
* '''value''': the amount healed.
* Use common keys and tags for abilities with a value.

=== Extra keys used by the ''[regenerate]'' ability ===
* '''value''': the amount healed.
* Use common keys and tags for abilities with a value

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* Use common keys and tags for abilities with a value
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys and tags used by the ''[defense]'' ability ===
* '''value''': set defense to this value. Warning, the chance to be hit decrease when value of ability increase.
* Use common keys and tags for abilities with a value

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* Use common keys and tags for abilities with a value
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect. If you use [affect_adjacent] the terrain under and adjacent to adjacent unit will be changed.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* Use Common keys and tags for abilities with a value
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.
* '''radius''': {{DevFeature1.19|15}} defines the radius of the ability, by default only the terrain the user is on and adjacent hexes are affected, but this can now be extended to a radius defined by '''radius''' ; if '''radius'''=all_map then the whole map will be affected.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected.
* '''[filter_adjacent_student]''': {{DevFeature1.19|10}} if an adjacent unit to student does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_student]. The variables $this_unit and $other_unit both work as you'd expect. Multiple [filter_adjacent_student] can be provided, all of which must pass for the ability to activate.
** '''radius''': {{DevFeature1.19|13}} determines the distance of units that can be filtered and not just adjacent units, '''radius''' is set to 1 by default.
* '''[filter_adjacent_student_location]''': {{DevFeature1.19|10}} like [filter_adjacent_student], but filters on locations instead of units. This is a shorthand for [filter_student][filter_location][filter_adjacent_location].
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
** '''description_affected''': {{DevFeature1.17|13}} becomes the '''description''' of the weapon special, without changing the '''description''' of the ability
** '''name_affected''': {{DevFeature1.17|13}} becomes the '''name''' of the weapon special, without changing the '''name''' of the ability
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[defense]''' {{DevFeature1.19|15}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' {{DevFeature1.19|16}} [defense] is no longer a weapon special but an ability.
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker '''value''' percentage of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50 by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this weapon special appears in. Note that such events get included when a unit with this weapon special first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special ===

{{DevFeature1.17|23}}

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

AbilitiesWML

2025-10-26T16:44:58Z

Newfrenchy83: /* Extra keys used by the [heals] ability */

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_opponent]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_opponent]''', while the student can be filtered with '''[filter_student]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* '''[defense]''' {{DevFeature1.19|16}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' .
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
** '''radius''': {{DevFeature1.19|13}} set to 1 by default, it determines the range within which units can be affected beyond immediately adjacent units, if the value is equal to 'full-map', the area is the entire map.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this ability appears in. Note that such events get included when a unit with this ability first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for abilities with a value ===

The '''[leasership]''', '''[heals]''', '''[regenerate]''',and '''[illuminates]''' abilities take values that specify how those abilities modify their respective base values.

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', the [leadership] value will be added to another [leadership] value= same if have same id=, for other abilities, the highest value between value= or base_value will be choosen.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[heals]'' ability ===
* '''value''': the amount healed.
* Use common keys and tags for abilities with a value.

=== Extra keys used by the ''[regenerate]'' ability ===

* Use common keys and tags for abilities with a value

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* Use common keys and tags for abilities with a value
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys and tags used by the ''[defense]'' ability ===

* Use common keys and tags for abilities with a value

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* Common keys and tags for abilities with a value
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* Use Common keys and tags for abilities with a value
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.
* '''radius''': {{DevFeature1.19|15}} defines the radius of the ability, by default only the terrain the user is on and adjacent hexes are affected, but this can now be extended to a radius defined by '''radius''' ; if '''radius'''=all_map then the whole map will be affected.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected.
* '''[filter_adjacent_student]''': {{DevFeature1.19|10}} if an adjacent unit to student does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_student]. The variables $this_unit and $other_unit both work as you'd expect. Multiple [filter_adjacent_student] can be provided, all of which must pass for the ability to activate.
** '''radius''': {{DevFeature1.19|13}} determines the distance of units that can be filtered and not just adjacent units, '''radius''' is set to 1 by default.
* '''[filter_adjacent_student_location]''': {{DevFeature1.19|10}} like [filter_adjacent_student], but filters on locations instead of units. This is a shorthand for [filter_student][filter_location][filter_adjacent_location].
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
** '''description_affected''': {{DevFeature1.17|13}} becomes the '''description''' of the weapon special, without changing the '''description''' of the ability
** '''name_affected''': {{DevFeature1.17|13}} becomes the '''name''' of the weapon special, without changing the '''name''' of the ability
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[defense]''' {{DevFeature1.19|15}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' {{DevFeature1.19|16}} [defense] is no longer a weapon special but an ability.
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker '''value''' percentage of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50 by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this weapon special appears in. Note that such events get included when a unit with this weapon special first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special ===

{{DevFeature1.17|23}}

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

AbilitiesWML

2025-10-26T15:28:58Z

Newfrenchy83: /* Common keys and tags for abilities with a value */

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_opponent]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_opponent]''', while the student can be filtered with '''[filter_student]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* '''[defense]''' {{DevFeature1.19|16}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' .
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
** '''radius''': {{DevFeature1.19|13}} set to 1 by default, it determines the range within which units can be affected beyond immediately adjacent units, if the value is equal to 'full-map', the area is the entire map.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this ability appears in. Note that such events get included when a unit with this ability first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for abilities with a value ===

The '''[leasership]''', '''[heals]''', '''[regenerate]''',and '''[illuminates]''' abilities take values that specify how those abilities modify their respective base values.

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', the [leadership] value will be added to another [leadership] value= same if have same id=, for other abilities, the highest value between value= or base_value will be choosen.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[heals]'' ability ===

* Use common keys and tags for abilities with a value.

=== Extra keys used by the ''[regenerate]'' ability ===

* Use common keys and tags for abilities with a value

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* Use common keys and tags for abilities with a value
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys and tags used by the ''[defense]'' ability ===

* Use common keys and tags for abilities with a value

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* Common keys and tags for abilities with a value
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* Use Common keys and tags for abilities with a value
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.
* '''radius''': {{DevFeature1.19|15}} defines the radius of the ability, by default only the terrain the user is on and adjacent hexes are affected, but this can now be extended to a radius defined by '''radius''' ; if '''radius'''=all_map then the whole map will be affected.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected.
* '''[filter_adjacent_student]''': {{DevFeature1.19|10}} if an adjacent unit to student does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_student]. The variables $this_unit and $other_unit both work as you'd expect. Multiple [filter_adjacent_student] can be provided, all of which must pass for the ability to activate.
** '''radius''': {{DevFeature1.19|13}} determines the distance of units that can be filtered and not just adjacent units, '''radius''' is set to 1 by default.
* '''[filter_adjacent_student_location]''': {{DevFeature1.19|10}} like [filter_adjacent_student], but filters on locations instead of units. This is a shorthand for [filter_student][filter_location][filter_adjacent_location].
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
** '''description_affected''': {{DevFeature1.17|13}} becomes the '''description''' of the weapon special, without changing the '''description''' of the ability
** '''name_affected''': {{DevFeature1.17|13}} becomes the '''name''' of the weapon special, without changing the '''name''' of the ability
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[defense]''' {{DevFeature1.19|15}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' {{DevFeature1.19|16}} [defense] is no longer a weapon special but an ability.
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker '''value''' percentage of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50 by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this weapon special appears in. Note that such events get included when a unit with this weapon special first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special ===

{{DevFeature1.17|23}}

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

AbilitiesWML

2025-10-26T15:28:30Z

Newfrenchy83: /* Common keys and tags for every ability */

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_opponent]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_opponent]''', while the student can be filtered with '''[filter_student]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* '''[defense]''' {{DevFeature1.19|16}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' .
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
** '''radius''': {{DevFeature1.19|13}} set to 1 by default, it determines the range within which units can be affected beyond immediately adjacent units, if the value is equal to 'full-map', the area is the entire map.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this ability appears in. Note that such events get included when a unit with this ability first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for abilities with a value ===

The '''[leasership]''', '''[heals]''', '''[regenerate]''',and '''[illuminates]''' abilities take values that specify how those abilities modify their respective base values.

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', the [leadership] value will be added to another [leadership] value= same if have same id=, for other abilities, the highest value beteween value= or base_value will be choosen.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[heals]'' ability ===

* Use common keys and tags for abilities with a value.

=== Extra keys used by the ''[regenerate]'' ability ===

* Use common keys and tags for abilities with a value

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* Use common keys and tags for abilities with a value
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys and tags used by the ''[defense]'' ability ===

* Use common keys and tags for abilities with a value

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* Common keys and tags for abilities with a value
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* Use Common keys and tags for abilities with a value
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.
* '''radius''': {{DevFeature1.19|15}} defines the radius of the ability, by default only the terrain the user is on and adjacent hexes are affected, but this can now be extended to a radius defined by '''radius''' ; if '''radius'''=all_map then the whole map will be affected.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected.
* '''[filter_adjacent_student]''': {{DevFeature1.19|10}} if an adjacent unit to student does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_student]. The variables $this_unit and $other_unit both work as you'd expect. Multiple [filter_adjacent_student] can be provided, all of which must pass for the ability to activate.
** '''radius''': {{DevFeature1.19|13}} determines the distance of units that can be filtered and not just adjacent units, '''radius''' is set to 1 by default.
* '''[filter_adjacent_student_location]''': {{DevFeature1.19|10}} like [filter_adjacent_student], but filters on locations instead of units. This is a shorthand for [filter_student][filter_location][filter_adjacent_location].
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
** '''description_affected''': {{DevFeature1.17|13}} becomes the '''description''' of the weapon special, without changing the '''description''' of the ability
** '''name_affected''': {{DevFeature1.17|13}} becomes the '''name''' of the weapon special, without changing the '''name''' of the ability
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[defense]''' {{DevFeature1.19|15}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' {{DevFeature1.19|16}} [defense] is no longer a weapon special but an ability.
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker '''value''' percentage of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50 by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this weapon special appears in. Note that such events get included when a unit with this weapon special first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special ===

{{DevFeature1.17|23}}

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

AbilitiesWML

2025-10-26T15:27:27Z

Newfrenchy83: /* Extra keys and tags used by the [defense] ability */

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_opponent]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_opponent]''', while the student can be filtered with '''[filter_student]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* '''[defense]''' {{DevFeature1.19|16}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' .
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''cumulative''': if set to 'yes', this ability will be cumulative with the base value for this ability. ''Beware of the bug with cumulative leadership in 1.16 https://github.com/wesnoth/wesnoth/issues/6466 , more info see below, in "Extra keys used by the ''leadership'' ability" section''. {{DevFeature1.17|5}}, bug fixed.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
** '''radius''': {{DevFeature1.19|13}} set to 1 by default, it determines the range within which units can be affected beyond immediately adjacent units, if the value is equal to 'full-map', the area is the entire map.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this ability appears in. Note that such events get included when a unit with this ability first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for abilities with a value ===

The '''[leasership]''', '''[heals]''', '''[regenerate]''',and '''[illuminates]''' abilities take values that specify how those abilities modify their respective base values.

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', the [leadership] value will be added to another [leadership] value= same if have same id=, for other abilities, the highest value beteween value= or base_value will be choosen.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[heals]'' ability ===

* Use common keys and tags for abilities with a value.

=== Extra keys used by the ''[regenerate]'' ability ===

* Use common keys and tags for abilities with a value

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* Use common keys and tags for abilities with a value
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys and tags used by the ''[defense]'' ability ===

* Use common keys and tags for abilities with a value

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* Common keys and tags for abilities with a value
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* Use Common keys and tags for abilities with a value
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.
* '''radius''': {{DevFeature1.19|15}} defines the radius of the ability, by default only the terrain the user is on and adjacent hexes are affected, but this can now be extended to a radius defined by '''radius''' ; if '''radius'''=all_map then the whole map will be affected.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected.
* '''[filter_adjacent_student]''': {{DevFeature1.19|10}} if an adjacent unit to student does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_student]. The variables $this_unit and $other_unit both work as you'd expect. Multiple [filter_adjacent_student] can be provided, all of which must pass for the ability to activate.
** '''radius''': {{DevFeature1.19|13}} determines the distance of units that can be filtered and not just adjacent units, '''radius''' is set to 1 by default.
* '''[filter_adjacent_student_location]''': {{DevFeature1.19|10}} like [filter_adjacent_student], but filters on locations instead of units. This is a shorthand for [filter_student][filter_location][filter_adjacent_location].
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
** '''description_affected''': {{DevFeature1.17|13}} becomes the '''description''' of the weapon special, without changing the '''description''' of the ability
** '''name_affected''': {{DevFeature1.17|13}} becomes the '''name''' of the weapon special, without changing the '''name''' of the ability
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[defense]''' {{DevFeature1.19|15}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' {{DevFeature1.19|16}} [defense] is no longer a weapon special but an ability.
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker '''value''' percentage of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50 by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this weapon special appears in. Note that such events get included when a unit with this weapon special first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special ===

{{DevFeature1.17|23}}

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

AbilitiesWML

2025-10-26T15:27:12Z

Newfrenchy83: /* Extra keys and tags used by the [resistance] ability */

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_opponent]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_opponent]''', while the student can be filtered with '''[filter_student]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* '''[defense]''' {{DevFeature1.19|16}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' .
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''cumulative''': if set to 'yes', this ability will be cumulative with the base value for this ability. ''Beware of the bug with cumulative leadership in 1.16 https://github.com/wesnoth/wesnoth/issues/6466 , more info see below, in "Extra keys used by the ''leadership'' ability" section''. {{DevFeature1.17|5}}, bug fixed.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
** '''radius''': {{DevFeature1.19|13}} set to 1 by default, it determines the range within which units can be affected beyond immediately adjacent units, if the value is equal to 'full-map', the area is the entire map.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this ability appears in. Note that such events get included when a unit with this ability first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for abilities with a value ===

The '''[leasership]''', '''[heals]''', '''[regenerate]''',and '''[illuminates]''' abilities take values that specify how those abilities modify their respective base values.

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', the [leadership] value will be added to another [leadership] value= same if have same id=, for other abilities, the highest value beteween value= or base_value will be choosen.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[heals]'' ability ===

* Use common keys and tags for abilities with a value.

=== Extra keys used by the ''[regenerate]'' ability ===

* Use common keys and tags for abilities with a value

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* Use common keys and tags for abilities with a value
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys and tags used by the ''[defense]'' ability ===

* Common keys and tags for abilities with a value

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* Common keys and tags for abilities with a value
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* Use Common keys and tags for abilities with a value
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.
* '''radius''': {{DevFeature1.19|15}} defines the radius of the ability, by default only the terrain the user is on and adjacent hexes are affected, but this can now be extended to a radius defined by '''radius''' ; if '''radius'''=all_map then the whole map will be affected.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected.
* '''[filter_adjacent_student]''': {{DevFeature1.19|10}} if an adjacent unit to student does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_student]. The variables $this_unit and $other_unit both work as you'd expect. Multiple [filter_adjacent_student] can be provided, all of which must pass for the ability to activate.
** '''radius''': {{DevFeature1.19|13}} determines the distance of units that can be filtered and not just adjacent units, '''radius''' is set to 1 by default.
* '''[filter_adjacent_student_location]''': {{DevFeature1.19|10}} like [filter_adjacent_student], but filters on locations instead of units. This is a shorthand for [filter_student][filter_location][filter_adjacent_location].
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
** '''description_affected''': {{DevFeature1.17|13}} becomes the '''description''' of the weapon special, without changing the '''description''' of the ability
** '''name_affected''': {{DevFeature1.17|13}} becomes the '''name''' of the weapon special, without changing the '''name''' of the ability
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[defense]''' {{DevFeature1.19|15}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' {{DevFeature1.19|16}} [defense] is no longer a weapon special but an ability.
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker '''value''' percentage of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50 by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this weapon special appears in. Note that such events get included when a unit with this weapon special first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special ===

{{DevFeature1.17|23}}

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

AbilitiesWML

2025-10-26T15:26:41Z

Newfrenchy83: /* Extra keys used by the [heals] ability */

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_opponent]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_opponent]''', while the student can be filtered with '''[filter_student]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* '''[defense]''' {{DevFeature1.19|16}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' .
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''cumulative''': if set to 'yes', this ability will be cumulative with the base value for this ability. ''Beware of the bug with cumulative leadership in 1.16 https://github.com/wesnoth/wesnoth/issues/6466 , more info see below, in "Extra keys used by the ''leadership'' ability" section''. {{DevFeature1.17|5}}, bug fixed.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
** '''radius''': {{DevFeature1.19|13}} set to 1 by default, it determines the range within which units can be affected beyond immediately adjacent units, if the value is equal to 'full-map', the area is the entire map.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this ability appears in. Note that such events get included when a unit with this ability first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for abilities with a value ===

The '''[leasership]''', '''[heals]''', '''[regenerate]''',and '''[illuminates]''' abilities take values that specify how those abilities modify their respective base values.

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', the [leadership] value will be added to another [leadership] value= same if have same id=, for other abilities, the highest value beteween value= or base_value will be choosen.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[heals]'' ability ===

* Use common keys and tags for abilities with a value.

=== Extra keys used by the ''[regenerate]'' ability ===

* Use common keys and tags for abilities with a value

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* '''add''': adds to resistance. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': subtracts from resistance.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys and tags used by the ''[defense]'' ability ===

* Common keys and tags for abilities with a value

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* Common keys and tags for abilities with a value
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* Use Common keys and tags for abilities with a value
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.
* '''radius''': {{DevFeature1.19|15}} defines the radius of the ability, by default only the terrain the user is on and adjacent hexes are affected, but this can now be extended to a radius defined by '''radius''' ; if '''radius'''=all_map then the whole map will be affected.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected.
* '''[filter_adjacent_student]''': {{DevFeature1.19|10}} if an adjacent unit to student does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_student]. The variables $this_unit and $other_unit both work as you'd expect. Multiple [filter_adjacent_student] can be provided, all of which must pass for the ability to activate.
** '''radius''': {{DevFeature1.19|13}} determines the distance of units that can be filtered and not just adjacent units, '''radius''' is set to 1 by default.
* '''[filter_adjacent_student_location]''': {{DevFeature1.19|10}} like [filter_adjacent_student], but filters on locations instead of units. This is a shorthand for [filter_student][filter_location][filter_adjacent_location].
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
** '''description_affected''': {{DevFeature1.17|13}} becomes the '''description''' of the weapon special, without changing the '''description''' of the ability
** '''name_affected''': {{DevFeature1.17|13}} becomes the '''name''' of the weapon special, without changing the '''name''' of the ability
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[defense]''' {{DevFeature1.19|15}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' {{DevFeature1.19|16}} [defense] is no longer a weapon special but an ability.
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker '''value''' percentage of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50 by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this weapon special appears in. Note that such events get included when a unit with this weapon special first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special ===

{{DevFeature1.17|23}}

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

AbilitiesWML

2025-10-26T15:26:29Z

Newfrenchy83: /* Extra keys used by the [regenerate] ability */

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_opponent]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_opponent]''', while the student can be filtered with '''[filter_student]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* '''[defense]''' {{DevFeature1.19|16}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' .
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''cumulative''': if set to 'yes', this ability will be cumulative with the base value for this ability. ''Beware of the bug with cumulative leadership in 1.16 https://github.com/wesnoth/wesnoth/issues/6466 , more info see below, in "Extra keys used by the ''leadership'' ability" section''. {{DevFeature1.17|5}}, bug fixed.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
** '''radius''': {{DevFeature1.19|13}} set to 1 by default, it determines the range within which units can be affected beyond immediately adjacent units, if the value is equal to 'full-map', the area is the entire map.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this ability appears in. Note that such events get included when a unit with this ability first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for abilities with a value ===

The '''[leasership]''', '''[heals]''', '''[regenerate]''',and '''[illuminates]''' abilities take values that specify how those abilities modify their respective base values.

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', the [leadership] value will be added to another [leadership] value= same if have same id=, for other abilities, the highest value beteween value= or base_value will be choosen.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[heals]'' ability ===

* Use Common keys and tags for abilities with a value.

=== Extra keys used by the ''[regenerate]'' ability ===

* Use common keys and tags for abilities with a value

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* '''add''': adds to resistance. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': subtracts from resistance.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys and tags used by the ''[defense]'' ability ===

* Common keys and tags for abilities with a value

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* Common keys and tags for abilities with a value
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* Use Common keys and tags for abilities with a value
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.
* '''radius''': {{DevFeature1.19|15}} defines the radius of the ability, by default only the terrain the user is on and adjacent hexes are affected, but this can now be extended to a radius defined by '''radius''' ; if '''radius'''=all_map then the whole map will be affected.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected.
* '''[filter_adjacent_student]''': {{DevFeature1.19|10}} if an adjacent unit to student does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_student]. The variables $this_unit and $other_unit both work as you'd expect. Multiple [filter_adjacent_student] can be provided, all of which must pass for the ability to activate.
** '''radius''': {{DevFeature1.19|13}} determines the distance of units that can be filtered and not just adjacent units, '''radius''' is set to 1 by default.
* '''[filter_adjacent_student_location]''': {{DevFeature1.19|10}} like [filter_adjacent_student], but filters on locations instead of units. This is a shorthand for [filter_student][filter_location][filter_adjacent_location].
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
** '''description_affected''': {{DevFeature1.17|13}} becomes the '''description''' of the weapon special, without changing the '''description''' of the ability
** '''name_affected''': {{DevFeature1.17|13}} becomes the '''name''' of the weapon special, without changing the '''name''' of the ability
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[defense]''' {{DevFeature1.19|15}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' {{DevFeature1.19|16}} [defense] is no longer a weapon special but an ability.
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker '''value''' percentage of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50 by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this weapon special appears in. Note that such events get included when a unit with this weapon special first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special ===

{{DevFeature1.17|23}}

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

AbilitiesWML

2025-10-26T15:26:02Z

Newfrenchy83: /* Extra keys used by the [illuminates] ability */

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_opponent]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_opponent]''', while the student can be filtered with '''[filter_student]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* '''[defense]''' {{DevFeature1.19|16}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' .
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''cumulative''': if set to 'yes', this ability will be cumulative with the base value for this ability. ''Beware of the bug with cumulative leadership in 1.16 https://github.com/wesnoth/wesnoth/issues/6466 , more info see below, in "Extra keys used by the ''leadership'' ability" section''. {{DevFeature1.17|5}}, bug fixed.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
** '''radius''': {{DevFeature1.19|13}} set to 1 by default, it determines the range within which units can be affected beyond immediately adjacent units, if the value is equal to 'full-map', the area is the entire map.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this ability appears in. Note that such events get included when a unit with this ability first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for abilities with a value ===

The '''[leasership]''', '''[heals]''', '''[regenerate]''',and '''[illuminates]''' abilities take values that specify how those abilities modify their respective base values.

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', the [leadership] value will be added to another [leadership] value= same if have same id=, for other abilities, the highest value beteween value= or base_value will be choosen.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[heals]'' ability ===

* Use Common keys and tags for abilities with a value.

=== Extra keys used by the ''[regenerate]'' ability ===

* Common keys and tags for abilities with a value

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* '''add''': adds to resistance. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': subtracts from resistance.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys and tags used by the ''[defense]'' ability ===

* Common keys and tags for abilities with a value

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* Common keys and tags for abilities with a value
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* Use Common keys and tags for abilities with a value
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.
* '''radius''': {{DevFeature1.19|15}} defines the radius of the ability, by default only the terrain the user is on and adjacent hexes are affected, but this can now be extended to a radius defined by '''radius''' ; if '''radius'''=all_map then the whole map will be affected.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected.
* '''[filter_adjacent_student]''': {{DevFeature1.19|10}} if an adjacent unit to student does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_student]. The variables $this_unit and $other_unit both work as you'd expect. Multiple [filter_adjacent_student] can be provided, all of which must pass for the ability to activate.
** '''radius''': {{DevFeature1.19|13}} determines the distance of units that can be filtered and not just adjacent units, '''radius''' is set to 1 by default.
* '''[filter_adjacent_student_location]''': {{DevFeature1.19|10}} like [filter_adjacent_student], but filters on locations instead of units. This is a shorthand for [filter_student][filter_location][filter_adjacent_location].
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
** '''description_affected''': {{DevFeature1.17|13}} becomes the '''description''' of the weapon special, without changing the '''description''' of the ability
** '''name_affected''': {{DevFeature1.17|13}} becomes the '''name''' of the weapon special, without changing the '''name''' of the ability
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[defense]''' {{DevFeature1.19|15}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' {{DevFeature1.19|16}} [defense] is no longer a weapon special but an ability.
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker '''value''' percentage of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50 by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this weapon special appears in. Note that such events get included when a unit with this weapon special first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special ===

{{DevFeature1.17|23}}

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

AbilitiesWML

2025-10-26T15:25:12Z

Newfrenchy83: /* Extra keys used by the [leadership] ability */

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_opponent]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_opponent]''', while the student can be filtered with '''[filter_student]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* '''[defense]''' {{DevFeature1.19|16}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' .
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''cumulative''': if set to 'yes', this ability will be cumulative with the base value for this ability. ''Beware of the bug with cumulative leadership in 1.16 https://github.com/wesnoth/wesnoth/issues/6466 , more info see below, in "Extra keys used by the ''leadership'' ability" section''. {{DevFeature1.17|5}}, bug fixed.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
** '''radius''': {{DevFeature1.19|13}} set to 1 by default, it determines the range within which units can be affected beyond immediately adjacent units, if the value is equal to 'full-map', the area is the entire map.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this ability appears in. Note that such events get included when a unit with this ability first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for abilities with a value ===

The '''[leasership]''', '''[heals]''', '''[regenerate]''',and '''[illuminates]''' abilities take values that specify how those abilities modify their respective base values.

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', the [leadership] value will be added to another [leadership] value= same if have same id=, for other abilities, the highest value beteween value= or base_value will be choosen.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[heals]'' ability ===

* Use Common keys and tags for abilities with a value.

=== Extra keys used by the ''[regenerate]'' ability ===

* Common keys and tags for abilities with a value

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* '''add''': adds to resistance. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': subtracts from resistance.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys and tags used by the ''[defense]'' ability ===

* Common keys and tags for abilities with a value

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* Common keys and tags for abilities with a value
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.
* '''radius''': {{DevFeature1.19|15}} defines the radius of the ability, by default only the terrain the user is on and adjacent hexes are affected, but this can now be extended to a radius defined by '''radius''' ; if '''radius'''=all_map then the whole map will be affected.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected.
* '''[filter_adjacent_student]''': {{DevFeature1.19|10}} if an adjacent unit to student does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_student]. The variables $this_unit and $other_unit both work as you'd expect. Multiple [filter_adjacent_student] can be provided, all of which must pass for the ability to activate.
** '''radius''': {{DevFeature1.19|13}} determines the distance of units that can be filtered and not just adjacent units, '''radius''' is set to 1 by default.
* '''[filter_adjacent_student_location]''': {{DevFeature1.19|10}} like [filter_adjacent_student], but filters on locations instead of units. This is a shorthand for [filter_student][filter_location][filter_adjacent_location].
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
** '''description_affected''': {{DevFeature1.17|13}} becomes the '''description''' of the weapon special, without changing the '''description''' of the ability
** '''name_affected''': {{DevFeature1.17|13}} becomes the '''name''' of the weapon special, without changing the '''name''' of the ability
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[defense]''' {{DevFeature1.19|15}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' {{DevFeature1.19|16}} [defense] is no longer a weapon special but an ability.
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker '''value''' percentage of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50 by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this weapon special appears in. Note that such events get included when a unit with this weapon special first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special ===

{{DevFeature1.17|23}}

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

AbilitiesWML

2025-10-26T15:24:42Z

Newfrenchy83: /* Extra keys and tags used by the [defense] ability */

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_opponent]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_opponent]''', while the student can be filtered with '''[filter_student]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* '''[defense]''' {{DevFeature1.19|16}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' .
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''cumulative''': if set to 'yes', this ability will be cumulative with the base value for this ability. ''Beware of the bug with cumulative leadership in 1.16 https://github.com/wesnoth/wesnoth/issues/6466 , more info see below, in "Extra keys used by the ''leadership'' ability" section''. {{DevFeature1.17|5}}, bug fixed.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
** '''radius''': {{DevFeature1.19|13}} set to 1 by default, it determines the range within which units can be affected beyond immediately adjacent units, if the value is equal to 'full-map', the area is the entire map.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this ability appears in. Note that such events get included when a unit with this ability first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for abilities with a value ===

The '''[leasership]''', '''[heals]''', '''[regenerate]''',and '''[illuminates]''' abilities take values that specify how those abilities modify their respective base values.

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', the [leadership] value will be added to another [leadership] value= same if have same id=, for other abilities, the highest value beteween value= or base_value will be choosen.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[heals]'' ability ===

* Use Common keys and tags for abilities with a value.

=== Extra keys used by the ''[regenerate]'' ability ===

* Common keys and tags for abilities with a value

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* '''add''': adds to resistance. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': subtracts from resistance.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys and tags used by the ''[defense]'' ability ===

* Common keys and tags for abilities with a value

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.
* '''max_value''': {{DevFeature1.19|2}} maximum leadership value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum leadership value. Default: no limit.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.
* '''radius''': {{DevFeature1.19|15}} defines the radius of the ability, by default only the terrain the user is on and adjacent hexes are affected, but this can now be extended to a radius defined by '''radius''' ; if '''radius'''=all_map then the whole map will be affected.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected.
* '''[filter_adjacent_student]''': {{DevFeature1.19|10}} if an adjacent unit to student does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_student]. The variables $this_unit and $other_unit both work as you'd expect. Multiple [filter_adjacent_student] can be provided, all of which must pass for the ability to activate.
** '''radius''': {{DevFeature1.19|13}} determines the distance of units that can be filtered and not just adjacent units, '''radius''' is set to 1 by default.
* '''[filter_adjacent_student_location]''': {{DevFeature1.19|10}} like [filter_adjacent_student], but filters on locations instead of units. This is a shorthand for [filter_student][filter_location][filter_adjacent_location].
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
** '''description_affected''': {{DevFeature1.17|13}} becomes the '''description''' of the weapon special, without changing the '''description''' of the ability
** '''name_affected''': {{DevFeature1.17|13}} becomes the '''name''' of the weapon special, without changing the '''name''' of the ability
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[defense]''' {{DevFeature1.19|15}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' {{DevFeature1.19|16}} [defense] is no longer a weapon special but an ability.
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker '''value''' percentage of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50 by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this weapon special appears in. Note that such events get included when a unit with this weapon special first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special ===

{{DevFeature1.17|23}}

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

AbilitiesWML

2025-10-26T15:24:29Z

Newfrenchy83: /* Extra keys used by the [regenerate] ability */

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_opponent]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_opponent]''', while the student can be filtered with '''[filter_student]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* '''[defense]''' {{DevFeature1.19|16}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' .
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''cumulative''': if set to 'yes', this ability will be cumulative with the base value for this ability. ''Beware of the bug with cumulative leadership in 1.16 https://github.com/wesnoth/wesnoth/issues/6466 , more info see below, in "Extra keys used by the ''leadership'' ability" section''. {{DevFeature1.17|5}}, bug fixed.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
** '''radius''': {{DevFeature1.19|13}} set to 1 by default, it determines the range within which units can be affected beyond immediately adjacent units, if the value is equal to 'full-map', the area is the entire map.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this ability appears in. Note that such events get included when a unit with this ability first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for abilities with a value ===

The '''[leasership]''', '''[heals]''', '''[regenerate]''',and '''[illuminates]''' abilities take values that specify how those abilities modify their respective base values.

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', the [leadership] value will be added to another [leadership] value= same if have same id=, for other abilities, the highest value beteween value= or base_value will be choosen.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[heals]'' ability ===

* Use Common keys and tags for abilities with a value.

=== Extra keys used by the ''[regenerate]'' ability ===

* Common keys and tags for abilities with a value

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* '''add''': adds to resistance. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': subtracts from resistance.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys and tags used by the ''[defense]'' ability ===

* '''value''': set defense to this value. The chance to be hits decrrease when value increase.
* '''add''': adds to defense. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': subtracts from defense.
* '''multiply''': multiplies defense value.
* '''divide''': divides defense value.
* '''max_value''': {{DevFeature1.19|2}} maximum defense value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum defense value. Default: no limit.

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.
* '''max_value''': {{DevFeature1.19|2}} maximum leadership value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum leadership value. Default: no limit.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.
* '''radius''': {{DevFeature1.19|15}} defines the radius of the ability, by default only the terrain the user is on and adjacent hexes are affected, but this can now be extended to a radius defined by '''radius''' ; if '''radius'''=all_map then the whole map will be affected.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected.
* '''[filter_adjacent_student]''': {{DevFeature1.19|10}} if an adjacent unit to student does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_student]. The variables $this_unit and $other_unit both work as you'd expect. Multiple [filter_adjacent_student] can be provided, all of which must pass for the ability to activate.
** '''radius''': {{DevFeature1.19|13}} determines the distance of units that can be filtered and not just adjacent units, '''radius''' is set to 1 by default.
* '''[filter_adjacent_student_location]''': {{DevFeature1.19|10}} like [filter_adjacent_student], but filters on locations instead of units. This is a shorthand for [filter_student][filter_location][filter_adjacent_location].
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
** '''description_affected''': {{DevFeature1.17|13}} becomes the '''description''' of the weapon special, without changing the '''description''' of the ability
** '''name_affected''': {{DevFeature1.17|13}} becomes the '''name''' of the weapon special, without changing the '''name''' of the ability
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[defense]''' {{DevFeature1.19|15}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' {{DevFeature1.19|16}} [defense] is no longer a weapon special but an ability.
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker '''value''' percentage of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50 by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this weapon special appears in. Note that such events get included when a unit with this weapon special first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special ===

{{DevFeature1.17|23}}

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

AbilitiesWML

2025-10-26T15:24:14Z

Newfrenchy83: /* Extra keys used by the [heals] ability */

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_opponent]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_opponent]''', while the student can be filtered with '''[filter_student]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* '''[defense]''' {{DevFeature1.19|16}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' .
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''cumulative''': if set to 'yes', this ability will be cumulative with the base value for this ability. ''Beware of the bug with cumulative leadership in 1.16 https://github.com/wesnoth/wesnoth/issues/6466 , more info see below, in "Extra keys used by the ''leadership'' ability" section''. {{DevFeature1.17|5}}, bug fixed.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
** '''radius''': {{DevFeature1.19|13}} set to 1 by default, it determines the range within which units can be affected beyond immediately adjacent units, if the value is equal to 'full-map', the area is the entire map.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this ability appears in. Note that such events get included when a unit with this ability first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for abilities with a value ===

The '''[leasership]''', '''[heals]''', '''[regenerate]''',and '''[illuminates]''' abilities take values that specify how those abilities modify their respective base values.

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', the [leadership] value will be added to another [leadership] value= same if have same id=, for other abilities, the highest value beteween value= or base_value will be choosen.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[heals]'' ability ===

* Use Common keys and tags for abilities with a value.

=== Extra keys used by the ''[regenerate]'' ability ===

* '''value''': the amount healed.
* '''add''': the number to add to the amount. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the amount.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''poison''': can be one of ''slowed'' or ''cured''.
* '''max_value''': {{DevFeature1.19|2}} maximum regenerate value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum regenerate value. Default: no limit.

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* '''add''': adds to resistance. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': subtracts from resistance.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys and tags used by the ''[defense]'' ability ===

* '''value''': set defense to this value. The chance to be hits decrrease when value increase.
* '''add''': adds to defense. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': subtracts from defense.
* '''multiply''': multiplies defense value.
* '''divide''': divides defense value.
* '''max_value''': {{DevFeature1.19|2}} maximum defense value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum defense value. Default: no limit.

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.
* '''max_value''': {{DevFeature1.19|2}} maximum leadership value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum leadership value. Default: no limit.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.
* '''radius''': {{DevFeature1.19|15}} defines the radius of the ability, by default only the terrain the user is on and adjacent hexes are affected, but this can now be extended to a radius defined by '''radius''' ; if '''radius'''=all_map then the whole map will be affected.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected.
* '''[filter_adjacent_student]''': {{DevFeature1.19|10}} if an adjacent unit to student does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_student]. The variables $this_unit and $other_unit both work as you'd expect. Multiple [filter_adjacent_student] can be provided, all of which must pass for the ability to activate.
** '''radius''': {{DevFeature1.19|13}} determines the distance of units that can be filtered and not just adjacent units, '''radius''' is set to 1 by default.
* '''[filter_adjacent_student_location]''': {{DevFeature1.19|10}} like [filter_adjacent_student], but filters on locations instead of units. This is a shorthand for [filter_student][filter_location][filter_adjacent_location].
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
** '''description_affected''': {{DevFeature1.17|13}} becomes the '''description''' of the weapon special, without changing the '''description''' of the ability
** '''name_affected''': {{DevFeature1.17|13}} becomes the '''name''' of the weapon special, without changing the '''name''' of the ability
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[defense]''' {{DevFeature1.19|15}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' {{DevFeature1.19|16}} [defense] is no longer a weapon special but an ability.
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker '''value''' percentage of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50 by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this weapon special appears in. Note that such events get included when a unit with this weapon special first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special ===

{{DevFeature1.17|23}}

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

AbilitiesWML

2025-10-26T15:21:51Z

Newfrenchy83: /* The [abilities] tag */

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_opponent]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_opponent]''', while the student can be filtered with '''[filter_student]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* '''[defense]''' {{DevFeature1.19|16}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' .
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''cumulative''': if set to 'yes', this ability will be cumulative with the base value for this ability. ''Beware of the bug with cumulative leadership in 1.16 https://github.com/wesnoth/wesnoth/issues/6466 , more info see below, in "Extra keys used by the ''leadership'' ability" section''. {{DevFeature1.17|5}}, bug fixed.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
** '''radius''': {{DevFeature1.19|13}} set to 1 by default, it determines the range within which units can be affected beyond immediately adjacent units, if the value is equal to 'full-map', the area is the entire map.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this ability appears in. Note that such events get included when a unit with this ability first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for abilities with a value ===

The '''[leasership]''', '''[heals]''', '''[regenerate]''',and '''[illuminates]''' abilities take values that specify how those abilities modify their respective base values.

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', the [leadership] value will be added to another [leadership] value= same if have same id=, for other abilities, the highest value beteween value= or base_value will be choosen.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[heals]'' ability ===

* '''value''': the amount healed.
* '''add''': the number to add to the amount. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the amount.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''poison''': can be one of ''slowed'' or ''cured''. ''slowed'' means poison will not take effect for adjacent units (it's not related to the weapon special "slows").
* '''max_value''': {{DevFeature1.19|2}} maximum heals value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum heals value. Default: no limit.

=== Extra keys used by the ''[regenerate]'' ability ===

* '''value''': the amount healed.
* '''add''': the number to add to the amount. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the amount.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''poison''': can be one of ''slowed'' or ''cured''.
* '''max_value''': {{DevFeature1.19|2}} maximum regenerate value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum regenerate value. Default: no limit.

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* '''add''': adds to resistance. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': subtracts from resistance.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys and tags used by the ''[defense]'' ability ===

* '''value''': set defense to this value. The chance to be hits decrrease when value increase.
* '''add''': adds to defense. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': subtracts from defense.
* '''multiply''': multiplies defense value.
* '''divide''': divides defense value.
* '''max_value''': {{DevFeature1.19|2}} maximum defense value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum defense value. Default: no limit.

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.
* '''max_value''': {{DevFeature1.19|2}} maximum leadership value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum leadership value. Default: no limit.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.
* '''radius''': {{DevFeature1.19|15}} defines the radius of the ability, by default only the terrain the user is on and adjacent hexes are affected, but this can now be extended to a radius defined by '''radius''' ; if '''radius'''=all_map then the whole map will be affected.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected.
* '''[filter_adjacent_student]''': {{DevFeature1.19|10}} if an adjacent unit to student does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_student]. The variables $this_unit and $other_unit both work as you'd expect. Multiple [filter_adjacent_student] can be provided, all of which must pass for the ability to activate.
** '''radius''': {{DevFeature1.19|13}} determines the distance of units that can be filtered and not just adjacent units, '''radius''' is set to 1 by default.
* '''[filter_adjacent_student_location]''': {{DevFeature1.19|10}} like [filter_adjacent_student], but filters on locations instead of units. This is a shorthand for [filter_student][filter_location][filter_adjacent_location].
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
** '''description_affected''': {{DevFeature1.17|13}} becomes the '''description''' of the weapon special, without changing the '''description''' of the ability
** '''name_affected''': {{DevFeature1.17|13}} becomes the '''name''' of the weapon special, without changing the '''name''' of the ability
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[defense]''' {{DevFeature1.19|15}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' {{DevFeature1.19|16}} [defense] is no longer a weapon special but an ability.
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker '''value''' percentage of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50 by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this weapon special appears in. Note that such events get included when a unit with this weapon special first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special ===

{{DevFeature1.17|23}}

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

AbilitiesWML

2025-10-17T18:44:33Z

Newfrenchy83: /* Extra keys used by the [regenerate] ability */

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_opponent]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_opponent]''', while the student can be filtered with '''[filter_student]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* '''[defense]''' {{DevFeature1.19|16}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' .
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''cumulative''': if set to 'yes', this ability will be cumulative with the base value for this ability. ''Beware of the bug with cumulative leadership in 1.16 https://github.com/wesnoth/wesnoth/issues/6466 , more info see below, in "Extra keys used by the ''leadership'' ability" section''. {{DevFeature1.17|5}}, bug fixed.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
** '''radius''': {{DevFeature1.19|13}} set to 1 by default, it determines the range within which units can be affected beyond immediately adjacent units, if the value is equal to 'full-map', the area is the entire map.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this ability appears in. Note that such events get included when a unit with this ability first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Extra keys used by the ''[heals]'' ability ===

* '''value''': the amount healed.
* '''add''': the number to add to the amount. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the amount.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''poison''': can be one of ''slowed'' or ''cured''. ''slowed'' means poison will not take effect for adjacent units (it's not related to the weapon special "slows").
* '''max_value''': {{DevFeature1.19|2}} maximum heals value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum heals value. Default: no limit.

=== Extra keys used by the ''[regenerate]'' ability ===

* '''value''': the amount healed.
* '''add''': the number to add to the amount. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the amount.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''poison''': can be one of ''slowed'' or ''cured''.
* '''max_value''': {{DevFeature1.19|2}} maximum regenerate value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum regenerate value. Default: no limit.

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* '''add''': adds to resistance. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': subtracts from resistance.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys and tags used by the ''[defense]'' ability ===

* '''value''': set defense to this value. The chance to be hits decrrease when value increase.
* '''add''': adds to defense. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': subtracts from defense.
* '''multiply''': multiplies defense value.
* '''divide''': divides defense value.
* '''max_value''': {{DevFeature1.19|2}} maximum defense value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum defense value. Default: no limit.

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.
* '''max_value''': {{DevFeature1.19|2}} maximum leadership value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum leadership value. Default: no limit.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.
* '''radius''': {{DevFeature1.19|15}} defines the radius of the ability, by default only the terrain the user is on and adjacent hexes are affected, but this can now be extended to a radius defined by '''radius''' ; if '''radius'''=all_map then the whole map will be affected.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected.
* '''[filter_adjacent_student]''': {{DevFeature1.19|10}} if an adjacent unit to student does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_student]. The variables $this_unit and $other_unit both work as you'd expect. Multiple [filter_adjacent_student] can be provided, all of which must pass for the ability to activate.
** '''radius''': {{DevFeature1.19|13}} determines the distance of units that can be filtered and not just adjacent units, '''radius''' is set to 1 by default.
* '''[filter_adjacent_student_location]''': {{DevFeature1.19|10}} like [filter_adjacent_student], but filters on locations instead of units. This is a shorthand for [filter_student][filter_location][filter_adjacent_location].
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
** '''description_affected''': {{DevFeature1.17|13}} becomes the '''description''' of the weapon special, without changing the '''description''' of the ability
** '''name_affected''': {{DevFeature1.17|13}} becomes the '''name''' of the weapon special, without changing the '''name''' of the ability
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[defense]''' {{DevFeature1.19|15}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' {{DevFeature1.19|16}} [defense] is no longer a weapon special but an ability.
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker '''value''' percentage of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50 by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this weapon special appears in. Note that such events get included when a unit with this weapon special first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special ===

{{DevFeature1.17|23}}

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

AbilitiesWML

2025-10-17T18:44:20Z

Newfrenchy83: /* Extra keys used by the [heals] ability */

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_opponent]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_opponent]''', while the student can be filtered with '''[filter_student]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* '''[defense]''' {{DevFeature1.19|16}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' .
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''cumulative''': if set to 'yes', this ability will be cumulative with the base value for this ability. ''Beware of the bug with cumulative leadership in 1.16 https://github.com/wesnoth/wesnoth/issues/6466 , more info see below, in "Extra keys used by the ''leadership'' ability" section''. {{DevFeature1.17|5}}, bug fixed.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
** '''radius''': {{DevFeature1.19|13}} set to 1 by default, it determines the range within which units can be affected beyond immediately adjacent units, if the value is equal to 'full-map', the area is the entire map.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this ability appears in. Note that such events get included when a unit with this ability first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Extra keys used by the ''[heals]'' ability ===

* '''value''': the amount healed.
* '''add''': the number to add to the amount. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the amount.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''poison''': can be one of ''slowed'' or ''cured''. ''slowed'' means poison will not take effect for adjacent units (it's not related to the weapon special "slows").
* '''max_value''': {{DevFeature1.19|2}} maximum heals value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum heals value. Default: no limit.

=== Extra keys used by the ''[regenerate]'' ability ===

* '''value''': the amount healed.
* '''poison''': can be one of ''slowed'' or ''cured''.
* '''max_value''': {{DevFeature1.19|2}} maximum regenerate value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum regenerate value. Default: no limit.

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* '''add''': adds to resistance. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': subtracts from resistance.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys and tags used by the ''[defense]'' ability ===

* '''value''': set defense to this value. The chance to be hits decrrease when value increase.
* '''add''': adds to defense. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': subtracts from defense.
* '''multiply''': multiplies defense value.
* '''divide''': divides defense value.
* '''max_value''': {{DevFeature1.19|2}} maximum defense value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum defense value. Default: no limit.

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.
* '''max_value''': {{DevFeature1.19|2}} maximum leadership value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum leadership value. Default: no limit.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.
* '''radius''': {{DevFeature1.19|15}} defines the radius of the ability, by default only the terrain the user is on and adjacent hexes are affected, but this can now be extended to a radius defined by '''radius''' ; if '''radius'''=all_map then the whole map will be affected.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected.
* '''[filter_adjacent_student]''': {{DevFeature1.19|10}} if an adjacent unit to student does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_student]. The variables $this_unit and $other_unit both work as you'd expect. Multiple [filter_adjacent_student] can be provided, all of which must pass for the ability to activate.
** '''radius''': {{DevFeature1.19|13}} determines the distance of units that can be filtered and not just adjacent units, '''radius''' is set to 1 by default.
* '''[filter_adjacent_student_location]''': {{DevFeature1.19|10}} like [filter_adjacent_student], but filters on locations instead of units. This is a shorthand for [filter_student][filter_location][filter_adjacent_location].
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
** '''description_affected''': {{DevFeature1.17|13}} becomes the '''description''' of the weapon special, without changing the '''description''' of the ability
** '''name_affected''': {{DevFeature1.17|13}} becomes the '''name''' of the weapon special, without changing the '''name''' of the ability
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[defense]''' {{DevFeature1.19|15}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' {{DevFeature1.19|16}} [defense] is no longer a weapon special but an ability.
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker '''value''' percentage of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50 by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this weapon special appears in. Note that such events get included when a unit with this weapon special first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special ===

{{DevFeature1.17|23}}

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

AbilitiesWML

2025-10-17T18:40:19Z

Newfrenchy83: /* Common keys and tags for specials with a value */

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_opponent]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_opponent]''', while the student can be filtered with '''[filter_student]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* '''[defense]''' {{DevFeature1.19|16}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' .
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''cumulative''': if set to 'yes', this ability will be cumulative with the base value for this ability. ''Beware of the bug with cumulative leadership in 1.16 https://github.com/wesnoth/wesnoth/issues/6466 , more info see below, in "Extra keys used by the ''leadership'' ability" section''. {{DevFeature1.17|5}}, bug fixed.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
** '''radius''': {{DevFeature1.19|13}} set to 1 by default, it determines the range within which units can be affected beyond immediately adjacent units, if the value is equal to 'full-map', the area is the entire map.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this ability appears in. Note that such events get included when a unit with this ability first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Extra keys used by the ''[heals]'' ability ===

* '''value''': the amount healed.
* '''poison''': can be one of ''slowed'' or ''cured''. ''slowed'' means poison will not take effect for adjacent units (it's not related to the weapon special "slows").
* '''max_value''': {{DevFeature1.19|2}} maximum heals value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum heals value. Default: no limit.

=== Extra keys used by the ''[regenerate]'' ability ===

* '''value''': the amount healed.
* '''poison''': can be one of ''slowed'' or ''cured''.
* '''max_value''': {{DevFeature1.19|2}} maximum regenerate value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum regenerate value. Default: no limit.

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* '''add''': adds to resistance. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': subtracts from resistance.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys and tags used by the ''[defense]'' ability ===

* '''value''': set defense to this value. The chance to be hits decrrease when value increase.
* '''add''': adds to defense. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': subtracts from defense.
* '''multiply''': multiplies defense value.
* '''divide''': divides defense value.
* '''max_value''': {{DevFeature1.19|2}} maximum defense value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum defense value. Default: no limit.

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.
* '''max_value''': {{DevFeature1.19|2}} maximum leadership value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum leadership value. Default: no limit.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.
* '''radius''': {{DevFeature1.19|15}} defines the radius of the ability, by default only the terrain the user is on and adjacent hexes are affected, but this can now be extended to a radius defined by '''radius''' ; if '''radius'''=all_map then the whole map will be affected.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected.
* '''[filter_adjacent_student]''': {{DevFeature1.19|10}} if an adjacent unit to student does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_student]. The variables $this_unit and $other_unit both work as you'd expect. Multiple [filter_adjacent_student] can be provided, all of which must pass for the ability to activate.
** '''radius''': {{DevFeature1.19|13}} determines the distance of units that can be filtered and not just adjacent units, '''radius''' is set to 1 by default.
* '''[filter_adjacent_student_location]''': {{DevFeature1.19|10}} like [filter_adjacent_student], but filters on locations instead of units. This is a shorthand for [filter_student][filter_location][filter_adjacent_location].
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
** '''description_affected''': {{DevFeature1.17|13}} becomes the '''description''' of the weapon special, without changing the '''description''' of the ability
** '''name_affected''': {{DevFeature1.17|13}} becomes the '''name''' of the weapon special, without changing the '''name''' of the ability
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[defense]''' {{DevFeature1.19|15}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' {{DevFeature1.19|16}} [defense] is no longer a weapon special but an ability.
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker '''value''' percentage of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50 by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this weapon special appears in. Note that such events get included when a unit with this weapon special first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''max_value''': {{DevFeature1.19|2}} maximum special value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum special value. Default: no limit.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special ===

{{DevFeature1.17|23}}

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

AbilitiesWML

2025-10-17T18:39:17Z

Newfrenchy83: /* Extra keys used by the [regenerate] ability */

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_opponent]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_opponent]''', while the student can be filtered with '''[filter_student]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* '''[defense]''' {{DevFeature1.19|16}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' .
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''cumulative''': if set to 'yes', this ability will be cumulative with the base value for this ability. ''Beware of the bug with cumulative leadership in 1.16 https://github.com/wesnoth/wesnoth/issues/6466 , more info see below, in "Extra keys used by the ''leadership'' ability" section''. {{DevFeature1.17|5}}, bug fixed.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
** '''radius''': {{DevFeature1.19|13}} set to 1 by default, it determines the range within which units can be affected beyond immediately adjacent units, if the value is equal to 'full-map', the area is the entire map.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this ability appears in. Note that such events get included when a unit with this ability first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Extra keys used by the ''[heals]'' ability ===

* '''value''': the amount healed.
* '''poison''': can be one of ''slowed'' or ''cured''. ''slowed'' means poison will not take effect for adjacent units (it's not related to the weapon special "slows").
* '''max_value''': {{DevFeature1.19|2}} maximum heals value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum heals value. Default: no limit.

=== Extra keys used by the ''[regenerate]'' ability ===

* '''value''': the amount healed.
* '''poison''': can be one of ''slowed'' or ''cured''.
* '''max_value''': {{DevFeature1.19|2}} maximum regenerate value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum regenerate value. Default: no limit.

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* '''add''': adds to resistance. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': subtracts from resistance.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys and tags used by the ''[defense]'' ability ===

* '''value''': set defense to this value. The chance to be hits decrrease when value increase.
* '''add''': adds to defense. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': subtracts from defense.
* '''multiply''': multiplies defense value.
* '''divide''': divides defense value.
* '''max_value''': {{DevFeature1.19|2}} maximum defense value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum defense value. Default: no limit.

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.
* '''max_value''': {{DevFeature1.19|2}} maximum leadership value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum leadership value. Default: no limit.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.
* '''radius''': {{DevFeature1.19|15}} defines the radius of the ability, by default only the terrain the user is on and adjacent hexes are affected, but this can now be extended to a radius defined by '''radius''' ; if '''radius'''=all_map then the whole map will be affected.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected.
* '''[filter_adjacent_student]''': {{DevFeature1.19|10}} if an adjacent unit to student does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_student]. The variables $this_unit and $other_unit both work as you'd expect. Multiple [filter_adjacent_student] can be provided, all of which must pass for the ability to activate.
** '''radius''': {{DevFeature1.19|13}} determines the distance of units that can be filtered and not just adjacent units, '''radius''' is set to 1 by default.
* '''[filter_adjacent_student_location]''': {{DevFeature1.19|10}} like [filter_adjacent_student], but filters on locations instead of units. This is a shorthand for [filter_student][filter_location][filter_adjacent_location].
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
** '''description_affected''': {{DevFeature1.17|13}} becomes the '''description''' of the weapon special, without changing the '''description''' of the ability
** '''name_affected''': {{DevFeature1.17|13}} becomes the '''name''' of the weapon special, without changing the '''name''' of the ability
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[defense]''' {{DevFeature1.19|15}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' {{DevFeature1.19|16}} [defense] is no longer a weapon special but an ability.
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker '''value''' percentage of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50 by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this weapon special appears in. Note that such events get included when a unit with this weapon special first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special ===

{{DevFeature1.17|23}}

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

AbilitiesWML

2025-10-17T18:38:53Z

Newfrenchy83: /* Extra keys used by the [heals] ability */

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_opponent]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_opponent]''', while the student can be filtered with '''[filter_student]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* '''[defense]''' {{DevFeature1.19|16}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' .
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''cumulative''': if set to 'yes', this ability will be cumulative with the base value for this ability. ''Beware of the bug with cumulative leadership in 1.16 https://github.com/wesnoth/wesnoth/issues/6466 , more info see below, in "Extra keys used by the ''leadership'' ability" section''. {{DevFeature1.17|5}}, bug fixed.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
** '''radius''': {{DevFeature1.19|13}} set to 1 by default, it determines the range within which units can be affected beyond immediately adjacent units, if the value is equal to 'full-map', the area is the entire map.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this ability appears in. Note that such events get included when a unit with this ability first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Extra keys used by the ''[heals]'' ability ===

* '''value''': the amount healed.
* '''poison''': can be one of ''slowed'' or ''cured''. ''slowed'' means poison will not take effect for adjacent units (it's not related to the weapon special "slows").
* '''max_value''': {{DevFeature1.19|2}} maximum heals value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum heals value. Default: no limit.

=== Extra keys used by the ''[regenerate]'' ability ===

* '''value''': the amount healed.
* '''poison''': can be one of ''slowed'' or ''cured''.

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* '''add''': adds to resistance. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': subtracts from resistance.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys and tags used by the ''[defense]'' ability ===

* '''value''': set defense to this value. The chance to be hits decrrease when value increase.
* '''add''': adds to defense. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': subtracts from defense.
* '''multiply''': multiplies defense value.
* '''divide''': divides defense value.
* '''max_value''': {{DevFeature1.19|2}} maximum defense value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum defense value. Default: no limit.

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.
* '''max_value''': {{DevFeature1.19|2}} maximum leadership value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum leadership value. Default: no limit.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.
* '''radius''': {{DevFeature1.19|15}} defines the radius of the ability, by default only the terrain the user is on and adjacent hexes are affected, but this can now be extended to a radius defined by '''radius''' ; if '''radius'''=all_map then the whole map will be affected.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected.
* '''[filter_adjacent_student]''': {{DevFeature1.19|10}} if an adjacent unit to student does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_student]. The variables $this_unit and $other_unit both work as you'd expect. Multiple [filter_adjacent_student] can be provided, all of which must pass for the ability to activate.
** '''radius''': {{DevFeature1.19|13}} determines the distance of units that can be filtered and not just adjacent units, '''radius''' is set to 1 by default.
* '''[filter_adjacent_student_location]''': {{DevFeature1.19|10}} like [filter_adjacent_student], but filters on locations instead of units. This is a shorthand for [filter_student][filter_location][filter_adjacent_location].
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
** '''description_affected''': {{DevFeature1.17|13}} becomes the '''description''' of the weapon special, without changing the '''description''' of the ability
** '''name_affected''': {{DevFeature1.17|13}} becomes the '''name''' of the weapon special, without changing the '''name''' of the ability
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[defense]''' {{DevFeature1.19|15}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' {{DevFeature1.19|16}} [defense] is no longer a weapon special but an ability.
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker '''value''' percentage of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50 by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this weapon special appears in. Note that such events get included when a unit with this weapon special first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special ===

{{DevFeature1.17|23}}

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

AbilitiesWML

2025-10-17T18:37:55Z

Newfrenchy83: /* Extra keys used by the [leadership] ability */

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_opponent]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_opponent]''', while the student can be filtered with '''[filter_student]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* '''[defense]''' {{DevFeature1.19|16}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' .
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''cumulative''': if set to 'yes', this ability will be cumulative with the base value for this ability. ''Beware of the bug with cumulative leadership in 1.16 https://github.com/wesnoth/wesnoth/issues/6466 , more info see below, in "Extra keys used by the ''leadership'' ability" section''. {{DevFeature1.17|5}}, bug fixed.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
** '''radius''': {{DevFeature1.19|13}} set to 1 by default, it determines the range within which units can be affected beyond immediately adjacent units, if the value is equal to 'full-map', the area is the entire map.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this ability appears in. Note that such events get included when a unit with this ability first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Extra keys used by the ''[heals]'' ability ===

* '''value''': the amount healed.
* '''poison''': can be one of ''slowed'' or ''cured''. ''slowed'' means poison will not take effect for adjacent units (it's not related to the weapon special "slows").

=== Extra keys used by the ''[regenerate]'' ability ===

* '''value''': the amount healed.
* '''poison''': can be one of ''slowed'' or ''cured''.

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* '''add''': adds to resistance. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': subtracts from resistance.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys and tags used by the ''[defense]'' ability ===

* '''value''': set defense to this value. The chance to be hits decrrease when value increase.
* '''add''': adds to defense. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': subtracts from defense.
* '''multiply''': multiplies defense value.
* '''divide''': divides defense value.
* '''max_value''': {{DevFeature1.19|2}} maximum defense value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum defense value. Default: no limit.

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.
* '''max_value''': {{DevFeature1.19|2}} maximum leadership value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum leadership value. Default: no limit.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.
* '''radius''': {{DevFeature1.19|15}} defines the radius of the ability, by default only the terrain the user is on and adjacent hexes are affected, but this can now be extended to a radius defined by '''radius''' ; if '''radius'''=all_map then the whole map will be affected.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected.
* '''[filter_adjacent_student]''': {{DevFeature1.19|10}} if an adjacent unit to student does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_student]. The variables $this_unit and $other_unit both work as you'd expect. Multiple [filter_adjacent_student] can be provided, all of which must pass for the ability to activate.
** '''radius''': {{DevFeature1.19|13}} determines the distance of units that can be filtered and not just adjacent units, '''radius''' is set to 1 by default.
* '''[filter_adjacent_student_location]''': {{DevFeature1.19|10}} like [filter_adjacent_student], but filters on locations instead of units. This is a shorthand for [filter_student][filter_location][filter_adjacent_location].
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
** '''description_affected''': {{DevFeature1.17|13}} becomes the '''description''' of the weapon special, without changing the '''description''' of the ability
** '''name_affected''': {{DevFeature1.17|13}} becomes the '''name''' of the weapon special, without changing the '''name''' of the ability
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[defense]''' {{DevFeature1.19|15}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' {{DevFeature1.19|16}} [defense] is no longer a weapon special but an ability.
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker '''value''' percentage of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50 by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this weapon special appears in. Note that such events get included when a unit with this weapon special first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special ===

{{DevFeature1.17|23}}

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

AbilitiesWML

2025-10-17T18:37:21Z

Newfrenchy83: /* Extra keys and tags used by the [defense] ability */

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_opponent]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_opponent]''', while the student can be filtered with '''[filter_student]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* '''[defense]''' {{DevFeature1.19|16}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' .
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''cumulative''': if set to 'yes', this ability will be cumulative with the base value for this ability. ''Beware of the bug with cumulative leadership in 1.16 https://github.com/wesnoth/wesnoth/issues/6466 , more info see below, in "Extra keys used by the ''leadership'' ability" section''. {{DevFeature1.17|5}}, bug fixed.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
** '''radius''': {{DevFeature1.19|13}} set to 1 by default, it determines the range within which units can be affected beyond immediately adjacent units, if the value is equal to 'full-map', the area is the entire map.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this ability appears in. Note that such events get included when a unit with this ability first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Extra keys used by the ''[heals]'' ability ===

* '''value''': the amount healed.
* '''poison''': can be one of ''slowed'' or ''cured''. ''slowed'' means poison will not take effect for adjacent units (it's not related to the weapon special "slows").

=== Extra keys used by the ''[regenerate]'' ability ===

* '''value''': the amount healed.
* '''poison''': can be one of ''slowed'' or ''cured''.

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* '''add''': adds to resistance. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': subtracts from resistance.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys and tags used by the ''[defense]'' ability ===

* '''value''': set defense to this value. The chance to be hits decrrease when value increase.
* '''add''': adds to defense. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': subtracts from defense.
* '''multiply''': multiplies defense value.
* '''divide''': divides defense value.
* '''max_value''': {{DevFeature1.19|2}} maximum defense value. Default: no limit.
* '''min_value''': {{DevFeature1.19|2}} minimum defense value. Default: no limit.

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.
* '''radius''': {{DevFeature1.19|15}} defines the radius of the ability, by default only the terrain the user is on and adjacent hexes are affected, but this can now be extended to a radius defined by '''radius''' ; if '''radius'''=all_map then the whole map will be affected.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected.
* '''[filter_adjacent_student]''': {{DevFeature1.19|10}} if an adjacent unit to student does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_student]. The variables $this_unit and $other_unit both work as you'd expect. Multiple [filter_adjacent_student] can be provided, all of which must pass for the ability to activate.
** '''radius''': {{DevFeature1.19|13}} determines the distance of units that can be filtered and not just adjacent units, '''radius''' is set to 1 by default.
* '''[filter_adjacent_student_location]''': {{DevFeature1.19|10}} like [filter_adjacent_student], but filters on locations instead of units. This is a shorthand for [filter_student][filter_location][filter_adjacent_location].
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
** '''description_affected''': {{DevFeature1.17|13}} becomes the '''description''' of the weapon special, without changing the '''description''' of the ability
** '''name_affected''': {{DevFeature1.17|13}} becomes the '''name''' of the weapon special, without changing the '''name''' of the ability
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[defense]''' {{DevFeature1.19|15}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' {{DevFeature1.19|16}} [defense] is no longer a weapon special but an ability.
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker '''value''' percentage of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50 by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this weapon special appears in. Note that such events get included when a unit with this weapon special first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special ===

{{DevFeature1.17|23}}

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

AbilitiesWML

2025-09-16T15:46:51Z

Newfrenchy83: /* The [abilities] tag */

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_opponent]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_opponent]''', while the student can be filtered with '''[filter_student]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* '''[defense]''' {{DevFeature1.19|16}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' .
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''cumulative''': if set to 'yes', this ability will be cumulative with the base value for this ability. ''Beware of the bug with cumulative leadership in 1.16 https://github.com/wesnoth/wesnoth/issues/6466 , more info see below, in "Extra keys used by the ''leadership'' ability" section''. {{DevFeature1.17|5}}, bug fixed.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
** '''radius''': {{DevFeature1.19|13}} set to 1 by default, it determines the range within which units can be affected beyond immediately adjacent units, if the value is equal to 'full-map', the area is the entire map.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this ability appears in. Note that such events get included when a unit with this ability first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Extra keys used by the ''[heals]'' ability ===

* '''value''': the amount healed.
* '''poison''': can be one of ''slowed'' or ''cured''. ''slowed'' means poison will not take effect for adjacent units (it's not related to the weapon special "slows").

=== Extra keys used by the ''[regenerate]'' ability ===

* '''value''': the amount healed.
* '''poison''': can be one of ''slowed'' or ''cured''.

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* '''add''': adds to resistance. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': subtracts from resistance.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys and tags used by the ''[defense]'' ability ===

* '''value''': set defense to this value. The chance to be hits decrrease when value increase.
* '''add''': adds to defense. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': subtracts from defense.
* '''multiply''': multiplies defense value.
* '''divide''': divides defense value.

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.
* '''radius''': {{DevFeature1.19|15}} defines the radius of the ability, by default only the terrain the user is on and adjacent hexes are affected, but this can now be extended to a radius defined by '''radius''' ; if '''radius'''=all_map then the whole map will be affected.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected.
* '''[filter_adjacent_student]''': {{DevFeature1.19|10}} if an adjacent unit to student does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_student]. The variables $this_unit and $other_unit both work as you'd expect. Multiple [filter_adjacent_student] can be provided, all of which must pass for the ability to activate.
** '''radius''': {{DevFeature1.19|13}} determines the distance of units that can be filtered and not just adjacent units, '''radius''' is set to 1 by default.
* '''[filter_adjacent_student_location]''': {{DevFeature1.19|10}} like [filter_adjacent_student], but filters on locations instead of units. This is a shorthand for [filter_student][filter_location][filter_adjacent_location].
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
** '''description_affected''': {{DevFeature1.17|13}} becomes the '''description''' of the weapon special, without changing the '''description''' of the ability
** '''name_affected''': {{DevFeature1.17|13}} becomes the '''name''' of the weapon special, without changing the '''name''' of the ability
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[defense]''' {{DevFeature1.19|15}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' {{DevFeature1.19|16}} [defense] is no longer a weapon special but an ability.
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker '''value''' percentage of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50 by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this weapon special appears in. Note that such events get included when a unit with this weapon special first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special ===

{{DevFeature1.17|23}}

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

AbilitiesWML

2025-09-16T15:41:28Z

Newfrenchy83: /* The [specials] tag */

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_opponent]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_opponent]''', while the student can be filtered with '''[filter_student]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''cumulative''': if set to 'yes', this ability will be cumulative with the base value for this ability. ''Beware of the bug with cumulative leadership in 1.16 https://github.com/wesnoth/wesnoth/issues/6466 , more info see below, in "Extra keys used by the ''leadership'' ability" section''. {{DevFeature1.17|5}}, bug fixed.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
** '''radius''': {{DevFeature1.19|13}} set to 1 by default, it determines the range within which units can be affected beyond immediately adjacent units, if the value is equal to 'full-map', the area is the entire map.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this ability appears in. Note that such events get included when a unit with this ability first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Extra keys used by the ''[heals]'' ability ===

* '''value''': the amount healed.
* '''poison''': can be one of ''slowed'' or ''cured''. ''slowed'' means poison will not take effect for adjacent units (it's not related to the weapon special "slows").

=== Extra keys used by the ''[regenerate]'' ability ===

* '''value''': the amount healed.
* '''poison''': can be one of ''slowed'' or ''cured''.

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* '''add''': adds to resistance. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': subtracts from resistance.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.
* '''radius''': {{DevFeature1.19|15}} defines the radius of the ability, by default only the terrain the user is on and adjacent hexes are affected, but this can now be extended to a radius defined by '''radius''' ; if '''radius'''=all_map then the whole map will be affected.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected.
* '''[filter_adjacent_student]''': {{DevFeature1.19|10}} if an adjacent unit to student does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_student]. The variables $this_unit and $other_unit both work as you'd expect. Multiple [filter_adjacent_student] can be provided, all of which must pass for the ability to activate.
** '''radius''': {{DevFeature1.19|13}} determines the distance of units that can be filtered and not just adjacent units, '''radius''' is set to 1 by default.
* '''[filter_adjacent_student_location]''': {{DevFeature1.19|10}} like [filter_adjacent_student], but filters on locations instead of units. This is a shorthand for [filter_student][filter_location][filter_adjacent_location].
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
** '''description_affected''': {{DevFeature1.17|13}} becomes the '''description''' of the weapon special, without changing the '''description''' of the ability
** '''name_affected''': {{DevFeature1.17|13}} becomes the '''name''' of the weapon special, without changing the '''name''' of the ability
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[defense]''' {{DevFeature1.19|15}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]''' {{DevFeature1.19|16}} [defense] is no longer a weapon special but an ability.
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker '''value''' percentage of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50 by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this weapon special appears in. Note that such events get included when a unit with this weapon special first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special ===

{{DevFeature1.17|23}}

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

AbilitiesWML

2025-08-12T12:55:49Z

Newfrenchy83: /* Extra tags and keys used by weapon specials as abilities */

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_opponent]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_opponent]''', while the student can be filtered with '''[filter_student]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''cumulative''': if set to 'yes', this ability will be cumulative with the base value for this ability. ''Beware of the bug with cumulative leadership in 1.16 https://github.com/wesnoth/wesnoth/issues/6466 , more info see below, in "Extra keys used by the ''leadership'' ability" section''. {{DevFeature1.17|5}}, bug fixed.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
** '''radius''': {{DevFeature1.19|13}} set to 1 by default, it determines the range within which units can be affected beyond immediately adjacent units, if the value is equal to 'full-map', the area is the entire map.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this ability appears in. Note that such events get included when a unit with this ability first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Extra keys used by the ''[heals]'' ability ===

* '''value''': the amount healed.
* '''poison''': can be one of ''slowed'' or ''cured''. ''slowed'' means poison will not take effect for adjacent units (it's not related to the weapon special "slows").

=== Extra keys used by the ''[regenerate]'' ability ===

* '''value''': the amount healed.
* '''poison''': can be one of ''slowed'' or ''cured''.

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* '''add''': adds to resistance. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': subtracts from resistance.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.
* '''radius''': {{DevFeature1.19|15}} defines the radius of the ability, by default only the terrain the user is on and adjacent hexes are affected, but this can now be extended to a radius defined by '''radius''' ; if '''radius'''=all_map then the whole map will be affected.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected.
* '''[filter_adjacent_student]''': {{DevFeature1.19|10}} if an adjacent unit to student does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_student]. The variables $this_unit and $other_unit both work as you'd expect. Multiple [filter_adjacent_student] can be provided, all of which must pass for the ability to activate.
** '''radius''': {{DevFeature1.19|13}} determines the distance of units that can be filtered and not just adjacent units, '''radius''' is set to 1 by default.
* '''[filter_adjacent_student_location]''': {{DevFeature1.19|10}} like [filter_adjacent_student], but filters on locations instead of units. This is a shorthand for [filter_student][filter_location][filter_adjacent_location].
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[defense]''' {{DevFeature1.19|15}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]'''
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker '''value''' percentage of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50 by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this weapon special appears in. Note that such events get included when a unit with this weapon special first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special ===

{{DevFeature1.17|23}}

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

AbilitiesWML

2025-08-12T12:52:33Z

Newfrenchy83: /* Extra tags and keys used by weapon specials as abilities */

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_opponent]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_opponent]''', while the student can be filtered with '''[filter_student]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''cumulative''': if set to 'yes', this ability will be cumulative with the base value for this ability. ''Beware of the bug with cumulative leadership in 1.16 https://github.com/wesnoth/wesnoth/issues/6466 , more info see below, in "Extra keys used by the ''leadership'' ability" section''. {{DevFeature1.17|5}}, bug fixed.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
** '''radius''': {{DevFeature1.19|13}} set to 1 by default, it determines the range within which units can be affected beyond immediately adjacent units, if the value is equal to 'full-map', the area is the entire map.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this ability appears in. Note that such events get included when a unit with this ability first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Extra keys used by the ''[heals]'' ability ===

* '''value''': the amount healed.
* '''poison''': can be one of ''slowed'' or ''cured''. ''slowed'' means poison will not take effect for adjacent units (it's not related to the weapon special "slows").

=== Extra keys used by the ''[regenerate]'' ability ===

* '''value''': the amount healed.
* '''poison''': can be one of ''slowed'' or ''cured''.

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* '''add''': adds to resistance. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': subtracts from resistance.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.
* '''radius''': {{DevFeature1.19|15}} defines the radius of the ability, by default only the terrain the user is on and adjacent hexes are affected, but this can now be extended to a radius defined by '''radius''' ; if '''radius'''=all_map then the whole map will be affected.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected.
* '''[filter_adjacent_student]''': {{DevFeature1.19|10}} if an adjacent unit to student does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_student]. The variables $this_unit and $other_unit both work as you'd expect. Multiple [filter_adjacent_student] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': {{DevFeature1.19|10}} like [filter_adjacent_student], but filters on locations instead of units. This is a shorthand for [filter_student][filter_location][filter_adjacent_location].
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[defense]''' {{DevFeature1.19|15}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]'''
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker '''value''' percentage of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50 by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this weapon special appears in. Note that such events get included when a unit with this weapon special first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special ===

{{DevFeature1.17|23}}

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

StandardUnitFilter

2025-08-11T09:14:49Z

Newfrenchy83:

{{WML Tags}}

From [[FilterWML]], this is the standard way of filtering units.

When a unit filter is applied to a map, first it applies to all units on the field,
based on their coordinates.
Next it applies to units in the recall list.
This is important to remember as it means, for example,
that the tag '''[kill]''' can be used to kill units in the recall list.

You can access the filtered unit within the filter as the ''$this_unit'' variable, see [[SingleUnitWML]] for the possible content of these variables

The term [[StandardUnitFilter]] means that the set of such keys and tags (see below) can appear at that point. Often a [[StandardUnitFilter]] needs to be included in a [filter] tag. But many tags take the [[StandardUnitFilter]] directly as an argument, like [[DirectActionsWML#.5Bkill.5D|[kill]]] and [[ConditionalActionsWML#.5Bhave_unit.5D|[have_unit]]] (which each accept a few additional keys of their own). See [[Special:WhatLinksHere/StandardUnitFilter]] for tags which can contain a StandardUnitFilter.

__TOC__

The following attributes and sub-tags are allowed:

* '''id''': unit matches the given id. This is the same as ''id'' in the [unit] tag. Note that it is independent of a unit's user-visible name, which can be internationalized independent of this (see [[SingleUnitWML]]). id= can be a comma-separated list, every unit with one of these ids matches.
* '''speaker''': alias for id (no comma-separated list supported)
* '''type''': matches the unit's type name (can be a list of types)
* '''type_adv_tree''': {{DevFeature1.13|7}} matches the type name of the unit and all its advancements (can be a list)
* '''race''': the race of the unit type. This can be a comma-separated list; the unit's race must match one of the given races. Mainline races are listed in data/core/units.cfg 
* '''variation''': the unit type variation id (can be a list of variation ids)
* '''has_variation''': matches if the unit type for the unit defines at least one of the variation ids provided as a comma-separated list
* '''upkeep''': {{DevFeature1.15|3}} The upkeep of the unit. Can be either a non-negative number or one of the special values ''loyal'', ''free'', ''full''. Note that while ''loyal'' and ''free'' are synonymous with an upkeep of 0, the value ''full'' is not synonymous with any single numeric value – it is equivalent to <code>$this_unit.level</code>.
* '''ability''': unit has an ability with the given id; see [[AbilitiesWML]]. This can be a comma-separated list. The unit must have at least one of the specified abilities.
* '''ability_type''': {{DevFeature1.13|7}} unit has an ability with the given type (tag name) - eg, ''ability_type=heals'' will match a unit with any healing ability.
* '''ability_type_active''': {{DevFeature1.13|8}} unit has an ''active'' ability with the given type (tag name).
* '''ability_id_active''': {{DevFeature1.15|13}} unit has an ''active'' ability with the given id; see [[AbilitiesWML]]
* '''trait''': {{DevFeature1.13|8}} This can be a comma-separated list. The unit must have at least one of the specified traits.
* '''status''': {{DevFeature1.13|0}} matches if the unit has the specified status active. This can be a comma-separated list, in which case the unit will match as long as it has one of the listed statuses active (note: possible statuses are listed on the [[SingleUnitWML]] page).
* '''side''': the unit is on the given side (can be a list)
* '''has_weapon''': the unit has a weapon with the given name {{DevFeature1.13|5}} Now deprecated
* {{anchor|has_attack|'''[has_attack]'''}}: {{DevFeature1.13|5}} the unit has a weapon matching the [[StandardWeaponFilter]]. If this is present, '''has_weapon''' is ignored.
* '''canrecruit''': yes if the unit can recruit (i.e. is a leader)
* '''gender''': female if the unit is female rather than the default of male
* '''role''': the unit has been assigned the given role; see '''[role]''', [[InternalActionsWML]]
* '''level''': the level of the unit (this can be a comma-separated list).
* '''defense''': current defense of the unit on current tile (chance to hit %, like in movement type definitions)
* '''movement_cost''': current movement cost of the unit on current tile. Can be a number, range, or comma separated range.
* '''x,y''': the position of the unit. Note: As a special case '''x,y=recall,recall''' matches units on the recall list. Note that the similar '''search_recall_list=yes''' key is only available as part of the '''[have_unit]''' condition tag, and is not otherwise considered part of a StandardUnitFilter.
* '''find_in''': name of an array or container variable; if present, the unit will not match unless a unit with the same '''id''' is already stored in the variable
* {{anchor|filter_vision|'''[filter_vision]'''}}: this tests whether or not the unit is currently visible
** '''visible''': yes or no, default yes. When "yes", this matches units that are not obscured by fog or shroud, and that are not hiding (via the {{tag|AbilitiesWML|hides}} ability). When "no", this matches units that are obscured by fog or shroud, or that are hiding.
** [[StandardSideFilter]] tags and keys. Filter for who may be able to see (or not see) the unit. If there is *at least one* matching side which can see the unit then the filter matches, and otherwise it fails to match.
* {{anchor|filter_wml|'''[filter_wml]'''}}: Converts the unit to WML (as if by '''[store_unit]''') and tests it against a [[FilterWML#Filtering_on_WML_data|WML filter]]. For a list of things in the WML that could be filtered on, see [[SingleUnitWML]] or open a saved game in a text editor. Note that this is slower than other methods, so if possible it's better to use other filter keys and tags; however, if the WML filter contains only a child '''[variables]''', then the unit is not converted to WML and the filter is matched only against the unit's variables (which are already WML).
* '''[and]''': an extra unit filter. Unless the unit also matches the [and] filter, then it will not count as a match. ''Note: [and],[or], and [not] filters are considered after the containing filter; they are then processed in the order encountered.''
* '''[or]''': an extra unit filter. If a unit matches the [or] filter, then it will count as a match regardless of conditions in previous filters or the containing filter.
* '''[not]''': an extra unit filter. If a unit matches the [not] filter, then that unit will not be considered a match by the containing filter.
* {{anchor|filter_adjacent|'''[filter_adjacent]'''}} with a StandardUnitFilter as argument. If present the correct number of adjacent units must match this filter.
**'''StandardUnitFilter''' tags and keys
** '''count''': a number, range, or comma separated range; default "1-6"
** '''adjacent''': a comma separated list of directions; default "n,ne,se,s,sw,nw" (see [[StandardLocationFilter#Directions|notes]])
** '''is_enemy''': a boolean specifying whether the adjacent unit must be an enemy or an ally (optional)
** '''$other_unit''': {{DevFeature1.13|2}} Within [filter_adjacent], the special variable $other_unit refers to the filtered unit from the enclosing filter, while $this_unit refers (as with all StandardUnitFilters) to the unit being filtered on.
** '''radius''': {{DevFeature1.19|13}} determines the distance of units that can be filtered and not just adjacent units, '''radius''' is set to 1 by default.
* '''[filter_location]''': [[StandardLocationFilter]] - the tile that the unit is standing on matches the location filter.
*'''[filter_side]''': The currently filtered unit's side must match this [[StandardSideFilter]] for the unit to match.
**[[StandardSideFilter]] tags and keys
* '''formula''': A formula using [[Wesnoth Formula Language]]. The <tt>self</tt> variable is set to the current $this_unit, and the formula should return a boolean. If it returns 0, the filter does not match. Otherwise, the filter does match. {{DevFeature1.13|5}} If the filter has a secondary unit, the formula can access it using the <code>other</code> variable. Both the unit and the secondary unit are a '''unit object''', with keys documented [[#Wesnoth_Formula_Language|below]]. Do not surround the formula in <code>$(...)</code>, since that will erase the <tt>self</tt> variable.
* '''lua_function''': the name of a [[LuaWML|Lua]] function in the global environment that takes a unit as an argument and returns true if the given unit matches the filter. {{DevFeature1.13|5}} Non-global functions can now be used here by building a dot-separated "path". Note that this is not actually interpreted as Lua code even though it superficially resembles it, so using a Lua keyword in the path will work, for example "my_filter_functions.goto" will correctly use the function which in actual Lua code would need to be referenced as <code>my_filter_functions["goto"]</code>.
* {{anchor|filter_ability|'''[experimental_filter_ability]'''}}: {{DevFeature1.17|17}} [[StandardAbilityFilter]] matches if the unit has an ability with the given properties - eg, ''[experimental_filter_ability]affect_self=yes'' will match a unit with any ability with ''affect_self=yes''. {{DevFeature1.19|5}} [experimental_filter_ability] deprecated, use [filter_ability] instead.
* {{anchor|filter_ability_active|'''[experimental_filter_ability_active]'''}}: {{DevFeature1.17|17}} [[StandardAbilityFilter]] matches if the unit has an ''active'' ability with the given properties - eg, ''[experimental_filter_ability_active]affect_adjacent=yes'' will match a unit with any ''active'' ability with ''[affect_adjacent]''. The attributes checked are the same as for [experimental_filter_ability]. {{DevFeature1.19|5}} [experimental_filter_ability_active] deprecated, use [filter_ability] instead.
* '''[filter_ability]''': {{DevFeature1.19|5}} [[StandardAbilityFilter]] matches if the unit has anability with the given properties - eg, ''[filter_ability]affect_adjacent=yes'' will match a unit with any ability with ''[affect_adjacent]''.
** '''active''': if active=yes, matches if the unit has an ''active'' ability with the given properties, if active=no, matches if the unit has an ability with the given properties regardless of 'active' or not. '''active''' is false by default.

== [[Wesnoth Formula Language]] ==

When using the '''formula''' key, the '''self''' and (if present) '''other''' objects support the following keys:

* '''x''', '''y''', '''loc''' - the latter is a '''location object''' such as what would be returned from [[Wesnoth_Formula_Language#loc|loc()]].
* '''id'''
* '''type'''
* '''name'''
* '''usage'''
* '''canrecruit''', '''leader'''
* '''undead''' - true if the unit has the ''not_living'' status
* '''attacks''' - a list of '''[[FilterWML#Filtering_Weapons|weapon objects]]'''
* '''abilities''' - a list of the ability IDs the unit possesses
* '''hitpoints''', '''max_hitpoints'''
* '''experience''', '''max_experience'''
* '''moves''', '''max_moves'''
* '''attacks_left''', '''max_attacks'''
* '''level''', '''full''' - '''full''' refers to the unit's level to support the formula <syntaxhighlight lang=wfl inline>upkeep = full</syntaxhighlight>
* '''traits''' - a list of the trait IDs
* '''objects''' {{DevFeature1.19|0}} - a list of the objects IDs
* '''advancements_taken''' {{DevFeature1.19|0}} - a list of the advancements taken IDs
* '''traits_count''' {{DevFeature1.19|0}} - number of traits used by unit regardless of IDs
* '''objects_count''' {{DevFeature1.19|0}} - number of objects used by unit regardless of IDs
* '''advancements_taken_count''' {{DevFeature1.19|0}} - number of advancements taken used by unit regardless of IDs
* '''extra_recruit'''
* '''advances_to'''
* '''status''' - a list of active statuses
* '''side_number'''
* '''cost'''
* '''upkeep'''
* '''loyal''' - a constant 0 to support the formula <syntaxhighlight lang=wfl inline>upkeep = loyal</syntaxhighlight>
* '''hidden'''
* '''petrified''' - true if the unit has the '''petrified''' status
* '''resting'''
* '''role'''
* '''race'''
* '''gender'''
* '''variation'''
* '''zoc'''
* '''alignment'''
* '''facing'''
* '''resistance''', '''movement_cost''', '''vision_cost''', '''jamming_cost''', '''defense''' - {{DevFeature1.15|3}} Maps containing the basic movetype data. The '''defense''' and '''resistance''' maps contain the actual defense and resistance values, rather than the values specified in the WML, so you do not need to subtract them from 100.
* '''flying''' {{DevFeature1.15|3}}
* '''fearless''', '''healthy''' {{DevFeature1.19|4}}
* '''vars''' - WFL variables owned by the unit, which can be set and used by FormulaAI
* '''wml_vars''' - the WML variables stored in the unit
* '''n''', '''s''', '''ne''', '''se''', '''nw''', '''sw''', '''lawful''', '''chaotic''', '''neutral''', '''liminal''', '''male''', '''female''' - these are all defined to be the equivalent string so that, for example, you can write a formula like <syntaxhighlight lang=wfl inline>alignment = liminal and gender = female</syntaxhighlight> without needing to quote the alignment and gender strings.

== A Note about Re-Using the Same Attribute ==
You are limited to having each attribute, such as '''id''', appear once or less in a [[StandardUnitFilter]]. However, this can be worked around. If you have several specific units you want excepted from matching, use a separate [or] subfilters for each one. Also you can use [not] subfilters. For example to kill ([kill] uses the standard unit filter) all units except Gwiti Ha'atel and Tanar you can do the following:

<syntaxhighlight lang='wml'>
[kill]
[not]
id=Gwiti Ha'atel
[/not]
[not]
id=Tanar
[/not]
[/kill]
</syntaxhighlight>

And similarly if you wanted to kill both Gwiti Ha'atel and Tanar, but no one else you could do the following:

<syntaxhighlight lang='wml'>
[kill]
id=Gwiti Ha'atel
[or]
id=Tanar
[/or]
[/kill]
</syntaxhighlight>

== Tutorial ==

* [[FilterWML/Examples_-_How_to_use_Filter|How To Use Filter (with examples)]]

== See Also ==

* [[FilterWML]]
* [[ReferenceWML]]

[[Category: WML Reference]]

AbilitiesWML

2025-08-11T09:06:48Z

Newfrenchy83: /* Extra tags and keys used by weapon specials as abilities */

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_opponent]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_opponent]''', while the student can be filtered with '''[filter_student]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''cumulative''': if set to 'yes', this ability will be cumulative with the base value for this ability. ''Beware of the bug with cumulative leadership in 1.16 https://github.com/wesnoth/wesnoth/issues/6466 , more info see below, in "Extra keys used by the ''leadership'' ability" section''. {{DevFeature1.17|5}}, bug fixed.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
** '''radius''': {{DevFeature1.19|13}} set to 1 by default, it determines the range within which units can be affected beyond immediately adjacent units, if the value is equal to 'full-map', the area is the entire map.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this ability appears in. Note that such events get included when a unit with this ability first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Extra keys used by the ''[heals]'' ability ===

* '''value''': the amount healed.
* '''poison''': can be one of ''slowed'' or ''cured''. ''slowed'' means poison will not take effect for adjacent units (it's not related to the weapon special "slows").

=== Extra keys used by the ''[regenerate]'' ability ===

* '''value''': the amount healed.
* '''poison''': can be one of ''slowed'' or ''cured''.

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* '''add''': adds to resistance. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': subtracts from resistance.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.
* '''radius''': {{DevFeature1.19|15}} defines the radius of the ability, by default only the terrain the user is on and adjacent hexes are affected, but this can now be extended to a radius defined by '''radius''' ; if '''radius'''=all_map then the whole map will be affected.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected.
* '''[filter_adjacent_student]''': {{DevFeature1.19|10}} if an adjacent unit to student does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_student]. The variables $this_unit and $other_unit both work as you'd expect. Multiple [filter_adjacent_student] can be provided, all of which must pass for the ability to activate.
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[defense]''' {{DevFeature1.19|15}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]'''
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker '''value''' percentage of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50 by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this weapon special appears in. Note that such events get included when a unit with this weapon special first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special ===

{{DevFeature1.17|23}}

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

AbilitiesWML

2025-07-31T12:48:05Z

Newfrenchy83: /* Extra keys used by the [illuminates] ability */

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_opponent]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_opponent]''', while the student can be filtered with '''[filter_student]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''cumulative''': if set to 'yes', this ability will be cumulative with the base value for this ability. ''Beware of the bug with cumulative leadership in 1.16 https://github.com/wesnoth/wesnoth/issues/6466 , more info see below, in "Extra keys used by the ''leadership'' ability" section''. {{DevFeature1.17|5}}, bug fixed.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
** '''radius''': {{DevFeature1.19|13}} set to 1 by default, it determines the range within which units can be affected beyond immediately adjacent units, if the value is equal to 'full-map', the area is the entire map.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this ability appears in. Note that such events get included when a unit with this ability first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Extra keys used by the ''[heals]'' ability ===

* '''value''': the amount healed.
* '''poison''': can be one of ''slowed'' or ''cured''. ''slowed'' means poison will not take effect for adjacent units (it's not related to the weapon special "slows").

=== Extra keys used by the ''[regenerate]'' ability ===

* '''value''': the amount healed.
* '''poison''': can be one of ''slowed'' or ''cured''.

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* '''add''': adds to resistance. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': subtracts from resistance.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.
* '''radius''': {{DevFeature1.19|15}} defines the radius of the ability, by default only the terrain the user is on and adjacent hexes are affected, but this can now be extended to a radius defined by '''radius''' ; if '''radius'''=all_map then the whole map will be affected.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected. '''Replaces''' '''[filter_self]''' of normal weapon specials.
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[defense]''' {{DevFeature1.19|15}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]'''
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker '''value''' percentage of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50 by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this weapon special appears in. Note that such events get included when a unit with this weapon special first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special ===

{{DevFeature1.17|23}}

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

AbilitiesWML

2025-07-31T12:47:22Z

Newfrenchy83: /* Extra keys used by the [leadership] ability */

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_opponent]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_opponent]''', while the student can be filtered with '''[filter_student]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''cumulative''': if set to 'yes', this ability will be cumulative with the base value for this ability. ''Beware of the bug with cumulative leadership in 1.16 https://github.com/wesnoth/wesnoth/issues/6466 , more info see below, in "Extra keys used by the ''leadership'' ability" section''. {{DevFeature1.17|5}}, bug fixed.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
** '''radius''': {{DevFeature1.19|13}} set to 1 by default, it determines the range within which units can be affected beyond immediately adjacent units, if the value is equal to 'full-map', the area is the entire map.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this ability appears in. Note that such events get included when a unit with this ability first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Extra keys used by the ''[heals]'' ability ===

* '''value''': the amount healed.
* '''poison''': can be one of ''slowed'' or ''cured''. ''slowed'' means poison will not take effect for adjacent units (it's not related to the weapon special "slows").

=== Extra keys used by the ''[regenerate]'' ability ===

* '''value''': the amount healed.
* '''poison''': can be one of ''slowed'' or ''cured''.

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* '''add''': adds to resistance. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': subtracts from resistance.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected. '''Replaces''' '''[filter_self]''' of normal weapon specials.
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[defense]''' {{DevFeature1.19|15}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]'''
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker '''value''' percentage of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50 by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this weapon special appears in. Note that such events get included when a unit with this weapon special first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special ===

{{DevFeature1.17|23}}

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

AbilitiesWML

2025-07-31T12:47:02Z

Newfrenchy83: /* Extra keys used by the [leadership] ability */

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_opponent]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_opponent]''', while the student can be filtered with '''[filter_student]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''cumulative''': if set to 'yes', this ability will be cumulative with the base value for this ability. ''Beware of the bug with cumulative leadership in 1.16 https://github.com/wesnoth/wesnoth/issues/6466 , more info see below, in "Extra keys used by the ''leadership'' ability" section''. {{DevFeature1.17|5}}, bug fixed.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
** '''radius''': {{DevFeature1.19|13}} set to 1 by default, it determines the range within which units can be affected beyond immediately adjacent units, if the value is equal to 'full-map', the area is the entire map.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this ability appears in. Note that such events get included when a unit with this ability first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Extra keys used by the ''[heals]'' ability ===

* '''value''': the amount healed.
* '''poison''': can be one of ''slowed'' or ''cured''. ''slowed'' means poison will not take effect for adjacent units (it's not related to the weapon special "slows").

=== Extra keys used by the ''[regenerate]'' ability ===

* '''value''': the amount healed.
* '''poison''': can be one of ''slowed'' or ''cured''.

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* '''add''': adds to resistance. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': subtracts from resistance.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.
* '''radius''': {{DevFeature1.19|15}} defines the radius of the ability, by default only the terrain the user is on and adjacent hexes are affected, but this can now be extended to a radius defined by '''radius''' ; if '''radius'''=all_map then the whole map will be affected.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected. '''Replaces''' '''[filter_self]''' of normal weapon specials.
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[defense]''' {{DevFeature1.19|15}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]'''
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker '''value''' percentage of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50 by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this weapon special appears in. Note that such events get included when a unit with this weapon special first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special ===

{{DevFeature1.17|23}}

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

AbilitiesWML

2025-07-24T08:48:24Z

Newfrenchy83: /* The [specials] tag */

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_opponent]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_opponent]''', while the student can be filtered with '''[filter_student]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''cumulative''': if set to 'yes', this ability will be cumulative with the base value for this ability. ''Beware of the bug with cumulative leadership in 1.16 https://github.com/wesnoth/wesnoth/issues/6466 , more info see below, in "Extra keys used by the ''leadership'' ability" section''. {{DevFeature1.17|5}}, bug fixed.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
** '''radius''': {{DevFeature1.19|13}} set to 1 by default, it determines the range within which units can be affected beyond immediately adjacent units, if the value is equal to 'full-map', the area is the entire map.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this ability appears in. Note that such events get included when a unit with this ability first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Extra keys used by the ''[heals]'' ability ===

* '''value''': the amount healed.
* '''poison''': can be one of ''slowed'' or ''cured''. ''slowed'' means poison will not take effect for adjacent units (it's not related to the weapon special "slows").

=== Extra keys used by the ''[regenerate]'' ability ===

* '''value''': the amount healed.
* '''poison''': can be one of ''slowed'' or ''cured''.

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* '''add''': adds to resistance. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': subtracts from resistance.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected. '''Replaces''' '''[filter_self]''' of normal weapon specials.
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[defense]''' {{DevFeature1.19|15}}: modifies the chances of being hit by the opponent's weapon, this value can be modified by the parry attribute, the accuracy attribute of the opponent's weapon, or by their special weapon '''[chance_to_hit]'''. Be careful, the more you increase the value, the less chance the opponent has of hitting you. Using same standard numerical attributes as '''[attacks]'''
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker half of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50% by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this weapon special appears in. Note that such events get included when a unit with this weapon special first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special ===

{{DevFeature1.17|23}}

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

AbilitiesWML

2025-06-10T09:26:30Z

Newfrenchy83:

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_opponent]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_opponent]''', while the student can be filtered with '''[filter_student]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''cumulative''': if set to 'yes', this ability will be cumulative with the base value for this ability. ''Beware of the bug with cumulative leadership in 1.16 https://github.com/wesnoth/wesnoth/issues/6466 , more info see below, in "Extra keys used by the ''leadership'' ability" section''. {{DevFeature1.17|5}}, bug fixed.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
** '''radius''': {{DevFeature1.19|13}} set to 1 by default, it determines the range within which units can be affected beyond immediately adjacent units, if the value is equal to 'full-map', the area is the entire map.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.{{DevFeature1.19|10}} If a unit does not match [filter_adjacent] it is not invalidated if the other units match the standard filters as well as the direction and number conditions.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this ability appears in. Note that such events get included when a unit with this ability first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Extra keys used by the ''[heals]'' ability ===

* '''value''': the amount healed.
* '''poison''': can be one of ''slowed'' or ''cured''. ''slowed'' means poison will not take effect for adjacent units (it's not related to the weapon special "slows").

=== Extra keys used by the ''[regenerate]'' ability ===

* '''value''': the amount healed.
* '''poison''': can be one of ''slowed'' or ''cured''.

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* '''add''': adds to resistance. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': subtracts from resistance.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected. '''Replaces''' '''[filter_self]''' of normal weapon specials.
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker half of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50% by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''' {{DevFeature1.19|10}}: if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this weapon special appears in. Note that such events get included when a unit with this weapon special first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special ===

{{DevFeature1.17|23}}

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

StandardUnitFilter

2025-06-09T18:16:43Z

Newfrenchy83:

{{WML Tags}}

From [[FilterWML]], this is the standard way of filtering units.

When a unit filter is applied to a map, first it applies to all units on the field,
based on their coordinates.
Next it applies to units in the recall list.
This is important to remember as it means, for example,
that the tag '''[kill]''' can be used to kill units in the recall list.

You can access the filtered unit within the filter as the ''$this_unit'' variable, see [[SingleUnitWML]] for the possible content of these variables

The term [[StandardUnitFilter]] means that the set of such keys and tags (see below) can appear at that point. Often a [[StandardUnitFilter]] needs to be included in a [filter] tag. But many tags take the [[StandardUnitFilter]] directly as an argument, like [[DirectActionsWML#.5Bkill.5D|[kill]]] and [[ConditionalActionsWML#.5Bhave_unit.5D|[have_unit]]] (which each accept a few additional keys of their own). See [[Special:WhatLinksHere/StandardUnitFilter]] for tags which can contain a StandardUnitFilter.

__TOC__

The following attributes and sub-tags are allowed:

* '''id''': unit matches the given id. This is the same as ''id'' in the [unit] tag. Note that it is independent of a unit's user-visible name, which can be internationalized independent of this (see [[SingleUnitWML]]). id= can be a comma-separated list, every unit with one of these ids matches.
* '''speaker''': alias for id (no comma-separated list supported)
* '''type''': matches the unit's type name (can be a list of types)
* '''type_adv_tree''': {{DevFeature1.13|7}} matches the type name of the unit and all its advancements (can be a list)
* '''race''': the race of the unit type. This can be a comma-separated list; the unit's race must match one of the given races. Mainline races are listed in data/core/units.cfg 
* '''variation''': the unit type variation id (can be a list of variation ids)
* '''has_variation''': matches if the unit type for the unit defines at least one of the variation ids provided as a comma-separated list
* '''upkeep''': {{DevFeature1.15|3}} The upkeep of the unit. Can be either a non-negative number or one of the special values ''loyal'', ''free'', ''full''. Note that while ''loyal'' and ''free'' are synonymous with an upkeep of 0, the value ''full'' is not synonymous with any single numeric value – it is equivalent to <code>$this_unit.level</code>.
* '''ability''': unit has an ability with the given id; see [[AbilitiesWML]]. This can be a comma-separated list. The unit must have at least one of the specified abilities.
* '''ability_type''': {{DevFeature1.13|7}} unit has an ability with the given type (tag name) - eg, ''ability_type=heals'' will match a unit with any healing ability.
* '''ability_type_active''': {{DevFeature1.13|8}} unit has an ''active'' ability with the given type (tag name).
* '''ability_id_active''': {{DevFeature1.15|13}} unit has an ''active'' ability with the given id; see [[AbilitiesWML]]
* '''trait''': {{DevFeature1.13|8}} This can be a comma-separated list. The unit must have at least one of the specified traits.
* '''status''': {{DevFeature1.13|0}} matches if the unit has the specified status active. This can be a comma-separated list, in which case the unit will match as long as it has one of the listed statuses active (note: possible statuses are listed on the [[SingleUnitWML]] page).
* '''side''': the unit is on the given side (can be a list)
* '''has_weapon''': the unit has a weapon with the given name {{DevFeature1.13|5}} Now deprecated
* {{anchor|has_attack|'''[has_attack]'''}}: {{DevFeature1.13|5}} the unit has a weapon matching the [[StandardWeaponFilter]]. If this is present, '''has_weapon''' is ignored.
* '''canrecruit''': yes if the unit can recruit (i.e. is a leader)
* '''gender''': female if the unit is female rather than the default of male
* '''role''': the unit has been assigned the given role; see '''[role]''', [[InternalActionsWML]]
* '''level''': the level of the unit (this can be a comma-separated list).
* '''defense''': current defense of the unit on current tile (chance to hit %, like in movement type definitions)
* '''movement_cost''': current movement cost of the unit on current tile. Can be a number, range, or comma separated range.
* '''x,y''': the position of the unit. Note: As a special case '''x,y=recall,recall''' matches units on the recall list. Note that the similar '''search_recall_list=yes''' key is only available as part of the '''[have_unit]''' condition tag, and is not otherwise considered part of a StandardUnitFilter.
* '''find_in''': name of an array or container variable; if present, the unit will not match unless a unit with the same '''id''' is already stored in the variable
* {{anchor|filter_vision|'''[filter_vision]'''}}: this tests whether or not the unit is currently visible
** '''visible''': yes or no, default yes. When "yes", this matches units that are not obscured by fog or shroud, and that are not hiding (via the {{tag|AbilitiesWML|hides}} ability). When "no", this matches units that are obscured by fog or shroud, or that are hiding.
** [[StandardSideFilter]] tags and keys. Filter for who may be able to see (or not see) the unit. If there is *at least one* matching side which can see the unit then the filter matches, and otherwise it fails to match.
* {{anchor|filter_wml|'''[filter_wml]'''}}: Converts the unit to WML (as if by '''[store_unit]''') and tests it against a [[FilterWML#Filtering_on_WML_data|WML filter]]. For a list of things in the WML that could be filtered on, see [[SingleUnitWML]] or open a saved game in a text editor. Note that this is slower than other methods, so if possible it's better to use other filter keys and tags; however, if the WML filter contains only a child '''[variables]''', then the unit is not converted to WML and the filter is matched only against the unit's variables (which are already WML).
* '''[and]''': an extra unit filter. Unless the unit also matches the [and] filter, then it will not count as a match. ''Note: [and],[or], and [not] filters are considered after the containing filter; they are then processed in the order encountered.''
* '''[or]''': an extra unit filter. If a unit matches the [or] filter, then it will count as a match regardless of conditions in previous filters or the containing filter.
* '''[not]''': an extra unit filter. If a unit matches the [not] filter, then that unit will not be considered a match by the containing filter.
* {{anchor|filter_adjacent|'''[filter_adjacent]'''}} with a StandardUnitFilter as argument. If present the correct number of adjacent units must match this filter. {{DevFeature1.19|10}} Inside abilities, can be used without [filter] tag.
**'''StandardUnitFilter''' tags and keys
** '''count''': a number, range, or comma separated range; default "1-6"
** '''adjacent''': a comma separated list of directions; default "n,ne,se,s,sw,nw" (see [[StandardLocationFilter#Directions|notes]])
** '''is_enemy''': a boolean specifying whether the adjacent unit must be an enemy or an ally (optional)
** '''$other_unit''': {{DevFeature1.13|2}} Within [filter_adjacent], the special variable $other_unit refers to the filtered unit from the enclosing filter, while $this_unit refers (as with all StandardUnitFilters) to the unit being filtered on.
* '''[filter_location]''': [[StandardLocationFilter]] - the tile that the unit is standing on matches the location filter.
*'''[filter_side]''': The currently filtered unit's side must match this [[StandardSideFilter]] for the unit to match.
**[[StandardSideFilter]] tags and keys
* '''formula''': A formula using [[Wesnoth Formula Language]]. The <tt>self</tt> variable is set to the current $this_unit, and the formula should return a boolean. If it returns 0, the filter does not match. Otherwise, the filter does match. {{DevFeature1.13|5}} If the filter has a secondary unit, the formula can access it using the <code>other</code> variable. Both the unit and the secondary unit are a '''unit object''', with keys documented [[#Wesnoth_Formula_Language|below]]. Do not surround the formula in <code>$(...)</code>, since that will erase the <tt>self</tt> variable.
* '''lua_function''': the name of a [[LuaWML|Lua]] function in the global environment that takes a unit as an argument and returns true if the given unit matches the filter. {{DevFeature1.13|5}} Non-global functions can now be used here by building a dot-separated "path". Note that this is not actually interpreted as Lua code even though it superficially resembles it, so using a Lua keyword in the path will work, for example "my_filter_functions.goto" will correctly use the function which in actual Lua code would need to be referenced as <code>my_filter_functions["goto"]</code>.
* {{anchor|filter_ability|'''[experimental_filter_ability]'''}}: {{DevFeature1.17|17}} [[StandardAbilityFilter]] matches if the unit has an ability with the given properties - eg, ''[experimental_filter_ability]affect_self=yes'' will match a unit with any ability with ''affect_self=yes''. {{DevFeature1.19|5}} [experimental_filter_ability] deprecated, use [filter_ability] instead.
* {{anchor|filter_ability_active|'''[experimental_filter_ability_active]'''}}: {{DevFeature1.17|17}} [[StandardAbilityFilter]] matches if the unit has an ''active'' ability with the given properties - eg, ''[experimental_filter_ability_active]affect_adjacent=yes'' will match a unit with any ''active'' ability with ''[affect_adjacent]''. The attributes checked are the same as for [experimental_filter_ability]. {{DevFeature1.19|5}} [experimental_filter_ability_active] deprecated, use [filter_ability] instead.
* '''[filter_ability]''': {{DevFeature1.19|5}} [[StandardAbilityFilter]] matches if the unit has anability with the given properties - eg, ''[filter_ability]affect_adjacent=yes'' will match a unit with any ability with ''[affect_adjacent]''.
** '''active''': if active=yes, matches if the unit has an ''active'' ability with the given properties, if active=no, matches if the unit has an ability with the given properties regardless of 'active' or not. '''active''' is false by default.

== [[Wesnoth Formula Language]] ==

When using the '''formula''' key, the '''self''' and (if present) '''other''' objects support the following keys:

* '''x''', '''y''', '''loc''' - the latter is a '''location object''' such as what would be returned from [[Wesnoth_Formula_Language#loc|loc()]].
* '''id'''
* '''type'''
* '''name'''
* '''usage'''
* '''canrecruit''', '''leader'''
* '''undead''' - true if the unit has the ''not_living'' status
* '''attacks''' - a list of '''[[FilterWML#Filtering_Weapons|weapon objects]]'''
* '''abilities''' - a list of the ability IDs the unit possesses
* '''hitpoints''', '''max_hitpoints'''
* '''experience''', '''max_experience'''
* '''moves''', '''max_moves'''
* '''attacks_left''', '''max_attacks'''
* '''level''', '''full''' - '''full''' refers to the unit's level to support the formula <syntaxhighlight lang=wfl inline>upkeep = full</syntaxhighlight>
* '''traits''' - a list of the trait IDs
* '''objects''' {{DevFeature1.19|0}} - a list of the objects IDs
* '''advancements_taken''' {{DevFeature1.19|0}} - a list of the advancements taken IDs
* '''traits_count''' {{DevFeature1.19|0}} - number of traits used by unit regardless of IDs
* '''objects_count''' {{DevFeature1.19|0}} - number of objects used by unit regardless of IDs
* '''advancements_taken_count''' {{DevFeature1.19|0}} - number of advancements taken used by unit regardless of IDs
* '''extra_recruit'''
* '''advances_to'''
* '''status''' - a list of active statuses
* '''side_number'''
* '''cost'''
* '''upkeep'''
* '''loyal''' - a constant 0 to support the formula <syntaxhighlight lang=wfl inline>upkeep = loyal</syntaxhighlight>
* '''hidden'''
* '''petrified''' - true if the unit has the '''petrified''' status
* '''resting'''
* '''role'''
* '''race'''
* '''gender'''
* '''variation'''
* '''zoc'''
* '''alignment'''
* '''facing'''
* '''resistance''', '''movement_cost''', '''vision_cost''', '''jamming_cost''', '''defense''' - {{DevFeature1.15|3}} Maps containing the basic movetype data. The '''defense''' and '''resistance''' maps contain the actual defense and resistance values, rather than the values specified in the WML, so you do not need to subtract them from 100.
* '''flying''' {{DevFeature1.15|3}}
* '''fearless''', '''healthy''' {{DevFeature1.19|4}}
* '''vars''' - WFL variables owned by the unit, which can be set and used by FormulaAI
* '''wml_vars''' - the WML variables stored in the unit
* '''n''', '''s''', '''ne''', '''se''', '''nw''', '''sw''', '''lawful''', '''chaotic''', '''neutral''', '''liminal''', '''male''', '''female''' - these are all defined to be the equivalent string so that, for example, you can write a formula like <syntaxhighlight lang=wfl inline>alignment = liminal and gender = female</syntaxhighlight> without needing to quote the alignment and gender strings.

== A Note about Re-Using the Same Attribute ==
You are limited to having each attribute, such as '''id''', appear once or less in a [[StandardUnitFilter]]. However, this can be worked around. If you have several specific units you want excepted from matching, use a separate [or] subfilters for each one. Also you can use [not] subfilters. For example to kill ([kill] uses the standard unit filter) all units except Gwiti Ha'atel and Tanar you can do the following:

<syntaxhighlight lang='wml'>
[kill]
[not]
id=Gwiti Ha'atel
[/not]
[not]
id=Tanar
[/not]
[/kill]
</syntaxhighlight>

And similarly if you wanted to kill both Gwiti Ha'atel and Tanar, but no one else you could do the following:

<syntaxhighlight lang='wml'>
[kill]
id=Gwiti Ha'atel
[or]
id=Tanar
[/or]
[/kill]
</syntaxhighlight>

== Tutorial ==

* [[FilterWML/Examples_-_How_to_use_Filter|How To Use Filter (with examples)]]

== See Also ==

* [[FilterWML]]
* [[ReferenceWML]]

[[Category: WML Reference]]

StandardUnitFilter

2025-06-09T13:43:30Z

Newfrenchy83:

{{WML Tags}}

From [[FilterWML]], this is the standard way of filtering units.

When a unit filter is applied to a map, first it applies to all units on the field,
based on their coordinates.
Next it applies to units in the recall list.
This is important to remember as it means, for example,
that the tag '''[kill]''' can be used to kill units in the recall list.

You can access the filtered unit within the filter as the ''$this_unit'' variable, see [[SingleUnitWML]] for the possible content of these variables

The term [[StandardUnitFilter]] means that the set of such keys and tags (see below) can appear at that point. Often a [[StandardUnitFilter]] needs to be included in a [filter] tag. But many tags take the [[StandardUnitFilter]] directly as an argument, like [[DirectActionsWML#.5Bkill.5D|[kill]]] and [[ConditionalActionsWML#.5Bhave_unit.5D|[have_unit]]] (which each accept a few additional keys of their own). See [[Special:WhatLinksHere/StandardUnitFilter]] for tags which can contain a StandardUnitFilter.

__TOC__

The following attributes and sub-tags are allowed:

* '''id''': unit matches the given id. This is the same as ''id'' in the [unit] tag. Note that it is independent of a unit's user-visible name, which can be internationalized independent of this (see [[SingleUnitWML]]). id= can be a comma-separated list, every unit with one of these ids matches.
* '''speaker''': alias for id (no comma-separated list supported)
* '''type''': matches the unit's type name (can be a list of types)
* '''type_adv_tree''': {{DevFeature1.13|7}} matches the type name of the unit and all its advancements (can be a list)
* '''race''': the race of the unit type. This can be a comma-separated list; the unit's race must match one of the given races. Mainline races are listed in data/core/units.cfg 
* '''variation''': the unit type variation id (can be a list of variation ids)
* '''has_variation''': matches if the unit type for the unit defines at least one of the variation ids provided as a comma-separated list
* '''upkeep''': {{DevFeature1.15|3}} The upkeep of the unit. Can be either a non-negative number or one of the special values ''loyal'', ''free'', ''full''. Note that while ''loyal'' and ''free'' are synonymous with an upkeep of 0, the value ''full'' is not synonymous with any single numeric value – it is equivalent to <code>$this_unit.level</code>.
* '''ability''': unit has an ability with the given id; see [[AbilitiesWML]]. This can be a comma-separated list. The unit must have at least one of the specified abilities.
* '''ability_type''': {{DevFeature1.13|7}} unit has an ability with the given type (tag name) - eg, ''ability_type=heals'' will match a unit with any healing ability.
* '''ability_type_active''': {{DevFeature1.13|8}} unit has an ''active'' ability with the given type (tag name).
* '''ability_id_active''': {{DevFeature1.15|13}} unit has an ''active'' ability with the given id; see [[AbilitiesWML]]
* '''trait''': {{DevFeature1.13|8}} This can be a comma-separated list. The unit must have at least one of the specified traits.
* '''status''': {{DevFeature1.13|0}} matches if the unit has the specified status active. This can be a comma-separated list, in which case the unit will match as long as it has one of the listed statuses active (note: possible statuses are listed on the [[SingleUnitWML]] page).
* '''side''': the unit is on the given side (can be a list)
* '''has_weapon''': the unit has a weapon with the given name {{DevFeature1.13|5}} Now deprecated
* {{anchor|has_attack|'''[has_attack]'''}}: {{DevFeature1.13|5}} the unit has a weapon matching the [[StandardWeaponFilter]]. If this is present, '''has_weapon''' is ignored.
* '''canrecruit''': yes if the unit can recruit (i.e. is a leader)
* '''gender''': female if the unit is female rather than the default of male
* '''role''': the unit has been assigned the given role; see '''[role]''', [[InternalActionsWML]]
* '''level''': the level of the unit (this can be a comma-separated list).
* '''defense''': current defense of the unit on current tile (chance to hit %, like in movement type definitions)
* '''movement_cost''': current movement cost of the unit on current tile. Can be a number, range, or comma separated range.
* '''x,y''': the position of the unit. Note: As a special case '''x,y=recall,recall''' matches units on the recall list. Note that the similar '''search_recall_list=yes''' key is only available as part of the '''[have_unit]''' condition tag, and is not otherwise considered part of a StandardUnitFilter.
* '''find_in''': name of an array or container variable; if present, the unit will not match unless a unit with the same '''id''' is already stored in the variable
* {{anchor|filter_vision|'''[filter_vision]'''}}: this tests whether or not the unit is currently visible
** '''visible''': yes or no, default yes. When "yes", this matches units that are not obscured by fog or shroud, and that are not hiding (via the {{tag|AbilitiesWML|hides}} ability). When "no", this matches units that are obscured by fog or shroud, or that are hiding.
** [[StandardSideFilter]] tags and keys. Filter for who may be able to see (or not see) the unit. If there is *at least one* matching side which can see the unit then the filter matches, and otherwise it fails to match.
* {{anchor|filter_wml|'''[filter_wml]'''}}: Converts the unit to WML (as if by '''[store_unit]''') and tests it against a [[FilterWML#Filtering_on_WML_data|WML filter]]. For a list of things in the WML that could be filtered on, see [[SingleUnitWML]] or open a saved game in a text editor. Note that this is slower than other methods, so if possible it's better to use other filter keys and tags; however, if the WML filter contains only a child '''[variables]''', then the unit is not converted to WML and the filter is matched only against the unit's variables (which are already WML).
* '''[and]''': an extra unit filter. Unless the unit also matches the [and] filter, then it will not count as a match. ''Note: [and],[or], and [not] filters are considered after the containing filter; they are then processed in the order encountered.''
* '''[or]''': an extra unit filter. If a unit matches the [or] filter, then it will count as a match regardless of conditions in previous filters or the containing filter.
* '''[not]''': an extra unit filter. If a unit matches the [not] filter, then that unit will not be considered a match by the containing filter.
* {{anchor|filter_adjacent|'''[filter_adjacent]'''}} with a StandardUnitFilter as argument; use inside a [filter] tag. If present the correct number of adjacent units must match this filter. {{DevFeature1.19|10}} Inside abilities, can be used without [filter] tag.
**'''StandardUnitFilter''' tags and keys
** '''count''': a number, range, or comma separated range; default "1-6"
** '''adjacent''': a comma separated list of directions; default "n,ne,se,s,sw,nw" (see [[StandardLocationFilter#Directions|notes]])
** '''is_enemy''': a boolean specifying whether the adjacent unit must be an enemy or an ally (optional)
** '''$other_unit''': {{DevFeature1.13|2}} Within [filter_adjacent], the special variable $other_unit refers to the filtered unit from the enclosing filter, while $this_unit refers (as with all StandardUnitFilters) to the unit being filtered on.
* '''[filter_location]''': [[StandardLocationFilter]] - the tile that the unit is standing on matches the location filter.
*'''[filter_side]''': The currently filtered unit's side must match this [[StandardSideFilter]] for the unit to match.
**[[StandardSideFilter]] tags and keys
* '''formula''': A formula using [[Wesnoth Formula Language]]. The <tt>self</tt> variable is set to the current $this_unit, and the formula should return a boolean. If it returns 0, the filter does not match. Otherwise, the filter does match. {{DevFeature1.13|5}} If the filter has a secondary unit, the formula can access it using the <code>other</code> variable. Both the unit and the secondary unit are a '''unit object''', with keys documented [[#Wesnoth_Formula_Language|below]]. Do not surround the formula in <code>$(...)</code>, since that will erase the <tt>self</tt> variable.
* '''lua_function''': the name of a [[LuaWML|Lua]] function in the global environment that takes a unit as an argument and returns true if the given unit matches the filter. {{DevFeature1.13|5}} Non-global functions can now be used here by building a dot-separated "path". Note that this is not actually interpreted as Lua code even though it superficially resembles it, so using a Lua keyword in the path will work, for example "my_filter_functions.goto" will correctly use the function which in actual Lua code would need to be referenced as <code>my_filter_functions["goto"]</code>.
* {{anchor|filter_ability|'''[experimental_filter_ability]'''}}: {{DevFeature1.17|17}} [[StandardAbilityFilter]] matches if the unit has an ability with the given properties - eg, ''[experimental_filter_ability]affect_self=yes'' will match a unit with any ability with ''affect_self=yes''. {{DevFeature1.19|5}} [experimental_filter_ability] deprecated, use [filter_ability] instead.
* {{anchor|filter_ability_active|'''[experimental_filter_ability_active]'''}}: {{DevFeature1.17|17}} [[StandardAbilityFilter]] matches if the unit has an ''active'' ability with the given properties - eg, ''[experimental_filter_ability_active]affect_adjacent=yes'' will match a unit with any ''active'' ability with ''[affect_adjacent]''. The attributes checked are the same as for [experimental_filter_ability]. {{DevFeature1.19|5}} [experimental_filter_ability_active] deprecated, use [filter_ability] instead.
* '''[filter_ability]''': {{DevFeature1.19|5}} [[StandardAbilityFilter]] matches if the unit has anability with the given properties - eg, ''[filter_ability]affect_adjacent=yes'' will match a unit with any ability with ''[affect_adjacent]''.
** '''active''': if active=yes, matches if the unit has an ''active'' ability with the given properties, if active=no, matches if the unit has an ability with the given properties regardless of 'active' or not. '''active''' is false by default.

== [[Wesnoth Formula Language]] ==

When using the '''formula''' key, the '''self''' and (if present) '''other''' objects support the following keys:

* '''x''', '''y''', '''loc''' - the latter is a '''location object''' such as what would be returned from [[Wesnoth_Formula_Language#loc|loc()]].
* '''id'''
* '''type'''
* '''name'''
* '''usage'''
* '''canrecruit''', '''leader'''
* '''undead''' - true if the unit has the ''not_living'' status
* '''attacks''' - a list of '''[[FilterWML#Filtering_Weapons|weapon objects]]'''
* '''abilities''' - a list of the ability IDs the unit possesses
* '''hitpoints''', '''max_hitpoints'''
* '''experience''', '''max_experience'''
* '''moves''', '''max_moves'''
* '''attacks_left''', '''max_attacks'''
* '''level''', '''full''' - '''full''' refers to the unit's level to support the formula <syntaxhighlight lang=wfl inline>upkeep = full</syntaxhighlight>
* '''traits''' - a list of the trait IDs
* '''objects''' {{DevFeature1.19|0}} - a list of the objects IDs
* '''advancements_taken''' {{DevFeature1.19|0}} - a list of the advancements taken IDs
* '''traits_count''' {{DevFeature1.19|0}} - number of traits used by unit regardless of IDs
* '''objects_count''' {{DevFeature1.19|0}} - number of objects used by unit regardless of IDs
* '''advancements_taken_count''' {{DevFeature1.19|0}} - number of advancements taken used by unit regardless of IDs
* '''extra_recruit'''
* '''advances_to'''
* '''status''' - a list of active statuses
* '''side_number'''
* '''cost'''
* '''upkeep'''
* '''loyal''' - a constant 0 to support the formula <syntaxhighlight lang=wfl inline>upkeep = loyal</syntaxhighlight>
* '''hidden'''
* '''petrified''' - true if the unit has the '''petrified''' status
* '''resting'''
* '''role'''
* '''race'''
* '''gender'''
* '''variation'''
* '''zoc'''
* '''alignment'''
* '''facing'''
* '''resistance''', '''movement_cost''', '''vision_cost''', '''jamming_cost''', '''defense''' - {{DevFeature1.15|3}} Maps containing the basic movetype data. The '''defense''' and '''resistance''' maps contain the actual defense and resistance values, rather than the values specified in the WML, so you do not need to subtract them from 100.
* '''flying''' {{DevFeature1.15|3}}
* '''fearless''', '''healthy''' {{DevFeature1.19|4}}
* '''vars''' - WFL variables owned by the unit, which can be set and used by FormulaAI
* '''wml_vars''' - the WML variables stored in the unit
* '''n''', '''s''', '''ne''', '''se''', '''nw''', '''sw''', '''lawful''', '''chaotic''', '''neutral''', '''liminal''', '''male''', '''female''' - these are all defined to be the equivalent string so that, for example, you can write a formula like <syntaxhighlight lang=wfl inline>alignment = liminal and gender = female</syntaxhighlight> without needing to quote the alignment and gender strings.

== A Note about Re-Using the Same Attribute ==
You are limited to having each attribute, such as '''id''', appear once or less in a [[StandardUnitFilter]]. However, this can be worked around. If you have several specific units you want excepted from matching, use a separate [or] subfilters for each one. Also you can use [not] subfilters. For example to kill ([kill] uses the standard unit filter) all units except Gwiti Ha'atel and Tanar you can do the following:

<syntaxhighlight lang='wml'>
[kill]
[not]
id=Gwiti Ha'atel
[/not]
[not]
id=Tanar
[/not]
[/kill]
</syntaxhighlight>

And similarly if you wanted to kill both Gwiti Ha'atel and Tanar, but no one else you could do the following:

<syntaxhighlight lang='wml'>
[kill]
id=Gwiti Ha'atel
[or]
id=Tanar
[/or]
[/kill]
</syntaxhighlight>

== Tutorial ==

* [[FilterWML/Examples_-_How_to_use_Filter|How To Use Filter (with examples)]]

== See Also ==

* [[FilterWML]]
* [[ReferenceWML]]

[[Category: WML Reference]]

AbilitiesWML

2025-05-29T16:15:36Z

Newfrenchy83: /* Common keys and tags for every ability */

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_opponent]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_opponent]''', while the student can be filtered with '''[filter_student]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''cumulative''': if set to 'yes', this ability will be cumulative with the base value for this ability. ''Beware of the bug with cumulative leadership in 1.16 https://github.com/wesnoth/wesnoth/issues/6466 , more info see below, in "Extra keys used by the ''leadership'' ability" section''. {{DevFeature1.17|5}}, bug fixed.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
** '''radius''': {{DevFeature1.19|13}} set to 1 by default, it determines the range within which units can be affected beyond immediately adjacent units, if the value is equal to 'full-map', the area is the entire map.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this ability appears in. Note that such events get included when a unit with this ability first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Extra keys used by the ''[heals]'' ability ===

* '''value''': the amount healed.
* '''poison''': can be one of ''slowed'' or ''cured''. ''slowed'' means poison will not take effect for adjacent units (it's not related to the weapon special "slows").

=== Extra keys used by the ''[regenerate]'' ability ===

* '''value''': the amount healed.
* '''poison''': can be one of ''slowed'' or ''cured''.

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* '''add''': adds to resistance. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': subtracts from resistance.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected. '''Replaces''' '''[filter_self]''' of normal weapon specials.
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker half of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50% by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} An [event] to be included into any scenario where a unit with this weapon special appears in. Note that such events get included when a unit with this weapon special first appears in the scenario, not automatically when the scenario begins (meaning that ''name=prestart'' events, for example, would usually never trigger). See [[WML_Abilities|WML Abilities]]. Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special ===

{{DevFeature1.17|23}}

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

AddonsWML

2024-11-03T17:33:24Z

Newfrenchy83: /* Common Tags and Keys */

{{WML Tags}}
== Creating add-ons in WML ==

An add-on is defined by a directory structure, there is no tag called '''[addon]'''. The directory must contain a '''_main.cfg''', and the name of the directory is treated as its '''id'''. There are different rules for add-ons that define a custom core, which are described in [[CoreWML]] and ignored for the purposes of this page.

The description of a downloaded add-on is found in '''_info.cfg''', the data for a locally authored add-on is in '''_server.pbl''' (see [[PblWML]]).

An add-on typically contains other files, see for example [[AddonStructure]] or [[BuildingCampaignsTheCampaignFile]].

== Which add-ons are active during gameplay ==

To help prevent clashes between add-ons, when starting a scenario the engine only loads the active add-ons. An add-on is active if one or more "add-on modules" is used by the game. If a game does not use any add-on module from your add-on, then your add-on won't be parsed at all. On the other hand, if the game uses any add-on module from your add-on, then your entire add-on will be parsed, relying on preprocessor defines to exclude parts that aren't relevant to the add-on module that is to be loaded.

Several toplevel tags are used to define an "add-on module":

* [[EraWML|'''[era]''']] - A multiplayer era
* [[CampaignWML|'''[campaign]''']] - A campaign, either single-player or multiplayer
* [[ScenarioWML#The .5Bscenario.5D tag|'''[scenario]''']] - A campaign scenario
* [[ScenarioWML#The .5Bmultiplayer.5D tag|'''[multiplayer]''']] - A multiplayer scenario
* [[ScenarioWML#The .5Btest.5D tag|'''[test]''']] - A test or demo scenario
* [[ModificationWML#The .5Bmodification.5D toplevel tag|'''[modification]''']] - A modification that can be selected in the campaign or multiplayer menu
* [[ModificationWML#The .5Bresource.5D toplevel tag|'''[resource]''']] - A resource that can be requested by any other add-on module

Notably, that list doesn't contain the [[UnitsWML|'''[units]''']] tag. For example, a multiplayer scenario which allows the player to choose any era but has scripted events that spawn Ageless Era units needs to activate those units' add-on by loading a resource from it.

== Common Tags and Keys ==

The following tags and keys are supported in most types of addon modules:

* '''id''': The addon module's unique ID. It must be unique across all addon module types, so for example there cannot be a '''[scenario]''' and a '''[multiplayer]''' with the same ID.
* '''addon_min_version''': The minimum version of your add-on with which this content is backwards compatible. Compared with the version string given in [[PblWML]]. If ''addon_min_version'' is not explicitly specified, it means compatible only with the same version. Clients in multiplayer must have add-on versions agreeing with the ''addon_min_versions'' of each others' content in order to play, and will be prompted to update otherwise.
* '''name''': (translatable) The visible name for the addon module, shown in the campaign selection or multiplayer game creation menu. (Not supported for '''[resource]''' since it is never visible anywhere.)
* '''description''': (translatable) The detailed description for the addon module, shown in the campaign selection or multiplayer game creation menu. (Also not supported for '''[resource]''', nor for '''[scenario]''' or '''[test]'''.)
* '''define'''='''''SYMBOL''''' When this addon module is active, the preprocessor symbol '''''SYMBOL''''' will be defined. See [[PreprocessorRef#.23ifdef_and_.23ifndef|ifdef]] for how this can be used to isolate parts of the file from other addon modules. Besides the addon module tag, only the tags '''[textdomain]''' and '''[binary_path]''' (see [[BinaryPathWML]]) should go outside of '''#ifdef ''SYMBOL'''''. This symbol will be defined ''before'' any .cfg is preprocessed. Note: If for some reason you don't want to place your '''[binary_path]''' outside your '''#ifdef ''SYMBOL''''' (perhaps it's causing conflicts with other addon modules), you can use binary-path-independent paths for the textdomain and any assets that are used in the addon module tag. This looks like '''icon=data/add-ons/whatever/something.png''' – essentially, any path beginning with '''data/'''.
* '''[event]''' - An event handler that will be registered when the addon module is active. See [[EventWML]].
* '''[lua]''' - Lua code that will be run when the addon module is loaded, before the '''preload''' event is fired. See [[LuaWML]].
* {{anchor|ai|'''[ai]'''}}: Defines an AI algorithm that can be selected by players at the join game screen. See [[Wesnoth_AI_Framework#The_.5Bai.5D_Tag_.E2.80.94_Top-level_Elements|here]] for details. This is not used in single-player.
** Note: This is not the place to define faction-specific AI parameters in an era. For that, place the '''[ai]''' tag in '''[multiplayer_side]'''.
** Note: This tag may not be supported in '''[resource]''', '''[scenario]''', or '''[test]'''.
* '''[options]''': Custom options. See [[OptionWML]] for details. Note: This may not be supported in '''[resource]''', '''[scenario]''', or '''[test]'''.
* {{anchor|load_resource|'''[load_resource]'''}}: Indicates a resource to load when this addon module is loaded.
** '''id''': The ID of the resource.
* {{anchor|modify_unit_type|'''[modify_unit_type]'''}} {{DevFeature1.15|2}}: Changes a unit type while this modification is active. The supported attributes are:
** '''type''' : the id of the unit type to change.
** '''set_experience''' : changes the unit type's max experience.
** '''set_cost''' : changes the unit type's recruit cost.
** '''set_advances_to''' : changes the unit type's advancements.
** '''add_advancement''' : adds a (list of comma separated) unit type(s) to the possible advancements of this unit type.
** '''remove_advancement''' : removes a (list of comma separated) unit type(s) from the possible advancements of this unit type.
** '''[advancement]''' : {{DevFeature1.19|5}} If a list of [advancement] is here, replace all [advancement] in unit type(s).
** '''[male]''' : {{DevFeature1.19|5}} If exist and unit type use this tag, key and tags previously listed contained in this tag will apply to male unit type(s) only.
** '''[female]''' : {{DevFeature1.19|5}} Same what [male] but for [female] sub_tags in unit type(s).
** '''[variation]''' : {{DevFeature1.19|5}} If '''variation_id''' matches with '''variation_id''' of a [variation] in unit type(s), same what [male] or [female] tags.

== See Also ==

* [[BinaryPathWML]] - Toplevel tag to define search paths for assets.
* [[UnitsWML]] - Toplevel tag to define units and unit-related data.
* [[TerrainWML]] - Toplevel tag to define terrain types.
* [[TerrainGraphicsWML]] - Toplevel tag to define how terrain is drawn.

EffectWML

2024-11-03T17:17:35Z

Newfrenchy83:

{{WML Tags}}

== [effect] ==

The tag [effect] is used to describe one modification to a unit. Any number of [effect] tags can be used to describe a complete modification.

Modifications are permanent changes to a unit; however using an [[DirectActionsWML#.5Bobject.5D|[object]]] with a limited ''duration'' to apply an [effect] will cause the unit to be rebuilt without the effect's effects when the duration expires.

The following keys and subtags are always recognized:
* '''[filter]''': only apply this effect if the affected unit matches. See [[StandardUnitFilter]] for details.
* '''times''': describes how many times the effect is applied. The default is to apply the effect once. Other possible value : "per level" which means that the effect is applied level times, where level is the unit level. {{DevFeature1.13|5}} Integers are now supported for ''times''.
* '''apply_to''': describes what the effect actually affects. New effect types can be added with [[LuaAPI/wesnoth#wesnoth.effects]]. Some examples can be seen in [https://github.com/wesnoth/wesnoth/blob/master/data/campaigns/World_Conquest/lua/game_mechanics/effects.lua World Conquest].

[effect] uses different keys depending on the value of '''apply_to'''. '''apply_to''' can take the following values:
* {{anchor|apply_to-new_attack|'''new_attack'''}}: will use all other keys and tags as the description of an attack that will be added to the unit. See [attack] in [[UnitTypeWML#Attacks|UnitTypeWML]].
* {{anchor|apply_to-remove_attacks|'''remove_attacks'''}}: remove the matching attacks. All tags from the attack filter construct will be used to match the attack; see [[FilterWML#Filtering Weapons|FilterWML]]. Do not use a [filter] tag otherwise it will not work properly.
* {{anchor|apply_to-attack|'''attack'''}}: find an attack and modify it. All tags from the attack filter construct will be used to match the attack; see [[FilterWML#Filtering Weapons|FilterWML]]. After that, the following keys and tags can be used to modify the attack. Note: do not use a [filter] tag. Just put the keys you want to filter on inside the [effect] tag.
** '''set_name''': change the attack's name (ie identifier).
** '''set_description''': change the attack's description (ie displayed name).
** '''set_type''': change the attack type. The standard values are '''blade''', '''pierce''', '''impact''', '''fire''', '''cold''', and '''arcane'''.
** '''set_range''': change the attack range. The standard values are '''ranged''' and '''melee'''.
** '''set_icon''': change the attack's icon.
** {{anchor|set_specials|'''[set_specials]'''}}: change the attack's specials. The specials to add are given exactly as in the [[AbilitiesWML#The_.5Bspecials.5D_tag|[specials]]] tag.
*** '''mode''': if '''append''', adds the given specials to the attack. If '''replace''', replaces the existing specials with the given ones. Default '''replace'''.
**** {{DevFeature1.15|3}} A deprecation warning is triggered unless the '''mode''' attribute is set, although the effect will still be '''replace'''. This is to allow the default to change in the 1.17.x series.
** '''remove_specials''': remove the listed specials. The value of this key is the comma-separated list of the id of the specials to remove. This key is always evaluated before a [set_specials] tags in the same [effect]
** '''[remove_specials]''': {{DevFeature1.19|6}} remove the listed specials. Use [[StandardAbilityFilter]], special removed if matches. This tag is always evaluated before a [set_specials] tags in the same [effect]
** '''increase_damage''': increases the attack's damage. This can be positive or negative, so you can use it to decrease damage as well. If it ends in a percent(''''%''''), the change in damage will be a percentage ratio of the attack's original damage.
** '''increase_attacks''': increases the number of attack strikes. Like '''increase_damage''', it can be positive or negative, or a percentage.
** '''increase_accuracy''': increases the attack accuracy; can be positive or negative, or a percentage
** '''increase_parry''': increases the attack parry bonus; can be positive or negative, or a percentage
** '''increase_movement_used''': {{DevFeature1.13|2}} increases the movement points used by the attack; can be positive or negative, or a percentage
** '''increase_attacks_used''': {{DevFeature1.17|13}} increases the attack points used by the attack; can be positive or negative, or a percentage
** '''set_damage''' {{DevFeature1.13|2}} like increase_damage, but sets the damage to a specific value instead of setting it relative to its original value
** '''set_attacks''' {{DevFeature1.13|2}} like increase_attacks, but sets the attacks to a specific value instead of setting it relative to its original value
** '''set_accuracy''' {{DevFeature1.13|2}} like increase_accuracy, but sets the accuracy to a specific value instead of setting it relative to its original value
** '''set_parry''' {{DevFeature1.13|2}} like increase_parry, but sets the parry to a specific value instead of setting it relative to its original value
** '''set_movement_used''' {{DevFeature1.13|2}} like increase_movement_used, but sets the movement used to a specific value instead of setting it relative to its original value
** '''set_attacks_used''' {{DevFeature1.17|13}} like increase_attacks_used, but sets the attacks used to a specific value instead of setting it relative to its original value
** '''attack_weight''': change the attack's attack_weight. See [attack] in [[UnitTypeWML#Attacks|UnitTypeWML]] for explanations about attack_weight.
** '''defense_weight''': change the attack's defense_weight. See [attack] in [[UnitTypeWML#Attacks|UnitTypeWML]] for explanations about defense_weight.
** '''set_min_range''' {{DevFeature1.19|4}} modify required distance between units in order to allow using attack
** '''set_max_range''' {{DevFeature1.19|4}} modify required distance between units in order to allow using attack
** '''increase_min_range''' {{DevFeature1.19|4}} modify required distance between units in order to allow using attack
** '''increase_max_range''' {{DevFeature1.19|4}} modify required distance between units in order to allow using attack
* {{anchor|apply_to-max_attacks|'''max_attacks'''}}: {{DevFeature1.13|2}} change the unit's maximum attacks per turn
** '''increase''': how much to increase by; can be positive or negative, or a percentage
* {{anchor|apply_to-hitpoints|'''hitpoints'''}}: modifies the unit's HP and/or max HP.
** '''increase''': the amount to increase the unit's HP.
** '''heal_full''': if present and not set to "no" the unit will be put back to full HP.
** '''increase_total''': will increase the total HP of the unit. Can be specified either as a negative or a positive value. It can also be specified as a percentage of the current total; i.e. "-50%" will cut max HP in half.
** '''violate_maximum''': it the unit ends up with more than its max HP after these modifications, and this key is present (set to any non-null value, ex. '''yes'''), the unit's HP won't be lowered to its max HP.
* {{anchor|apply_to-movement|'''movement'''}}: modifies the unit's movement points.
** '''increase''': maximum movement is increased by this amount. It can be positive, negative, or specified as a percentage.
** '''set''': maximum movement is set to a specific value.
** '''apply_to_vision''': {{DevFeature1.15|13}} if set to '''yes''' (which is the default), then the vision points will change by the same amount. See [[#Movement_and_Vision|Movement and Vision]].
* {{anchor|apply_to-vision|'''vision'''}}: {{DevFeature1.13|2}} modifies the unit's vision points. Note: this has side effects described in [[#Movement_and_Vision|Movement and Vision]].
** '''increase''': maximum vision is increased by this amount. It can be positive, negative, or specified as a percentage.
** '''set''': maximum vision is set to a specific value.
* {{anchor|apply_to-jamming|'''jamming'''}}: {{DevFeature1.13|2}} modifies the unit's jamming points.
** '''increase''': maximum jamming is increased by this amount. It can be positive, negative, or specified as a percentage.
** '''set''': maximum jamming is set to a specific value.
* {{anchor|apply_to-experience|'''experience'''}}: affects the unit's current XP.
** '''increase''': current XP is increased by this amount. It can be positive, negative, or specified as a percentage.
** '''set''': current XP is set to a specific value.
* {{anchor|apply_to-max_experience|'''max_experience'''}}: affects the amount of XP the unit needs for the next level.
** '''increase''': how to change the xp; again it can be negative, positive or a percentage.
** '''set''': current max XP is set to a specific value.
* {{anchor|apply_to-loyal|'''loyal'''}}: no keys associated. The affected unit will be loyal i.e have an upkeep of 0.
* {{anchor|apply_to-fearless|'''fearless'''}}: Add/Remove fearless attribute.
** '''set''': new value for fearless (boolean). Defaults to '''yes'''.
* {{anchor|apply_to-healthy|'''healthy'''}}: Add/Remove healthy attribute.
** '''set''': new value for healthy (boolean). Defaults to '''yes'''.
* {{anchor|apply_to_movement_costs|'''movement_costs'''}}: speed through specific terrain is modified
** '''replace''': If set to "yes", any new values replace the old ones. Otherwise, new values are added to old values (negative values allowed). Defaults to '''no'''.
** '''[movement_costs]''': a subtag that describes the new movement costs just like under [[UnitsWML#.5Bmovetype.5D|[movetype]]] if replace is set to "yes" or the addition if "no".
* {{anchor|apply_to-vision_costs|'''vision_costs'''}}: vision through specific terrain is modified
** '''replace''': If set to "yes", any new values replace the old ones. Otherwise, new values are added to old values (negative values allowed). Defaults to '''no'''.
** '''[vision_costs]''': a subtag that describes the new vision costs just like under [[UnitsWML#.5Bmovetype.5D|[movetype]]] if replace is set to "yes" or the addition if "no".
* {{anchor|apply_to-jamming_costs|'''jamming_costs'''}}: jamming through specific terrain is modified
** '''replace''': If set to "yes", any new values replace the old ones. Otherwise, new values are added to old values (negative values allowed). Defaults to '''no'''.
** '''[jamming_costs]''': a subtag that describes the new jamming costs just like under [[UnitsWML#.5Bmovetype.5D|[movetype]]] if replace is set to "yes" or the addition if "no".
* {{anchor|apply_to-defense|'''defense'''}}: Sets the unit's chance to be hit in specific terrain (100 - the unit's defense as shown in-game).
** '''replace''': If set to "yes", any new values replace the old ones. Otherwise, new values are added to old values. In most cases, adding a positive number makes the unit easier to hit, while adding a negative number makes the unit harder to hit. The new value is added to the absolute value of the old, and the sign of the old value is preserved. Defaults to '''no'''.
** '''[defense]''': a subtag that describes the new defense just like under [[UnitsWML#.5Bmovetype.5D|[movetype]]] if replace is set to "yes" or the addition if "no".
* {{anchor|apply_to-resistance|'''resistance'''}}: Sets percent damage taken from combat (100 - the unit's resistance as shown in-game)
** '''replace''': If set to "yes", any new values replace the old ones. Otherwise, new values are added to old values. Adding a positive number makes the unit take more damage, while adding a negative number makes the unit take less damage. Defaults to '''no'''.
** '''[resistance]''': a subtag that describes the new resistance just like under [[UnitsWML#.5Bmovetype.5D|[movetype]]] if replace is set to "yes" or the addition if "no".
* {{anchor|apply_to-variation|'''variation'''}}: switches the unit into one of its variations. Similar to the '''type''' effect below, this might not behave properly outside of [advancement].
** '''name''': the id of the variation to invoke.
* {{anchor|apply_to-type|'''type'''}}: transforms the unit into a new unit_type. This does not work in [trait]; in ActionWML it's recommended to use [transform_unit] instead of an [object] with this effect. This effect cannot be undone with [remove_object].
** '''name''': the id of the unit_type to invoke.
* {{anchor|apply_to-status|'''status'''}}: modifies the status affecting the unit.
** '''add''': a list of status modifications to add. Beware, these may be reapplied later, such as when the unit is recalled or levels up; if in an event, you can use [[InternalActionsWML|[store_unit]]] and [[DirectActionsWML|[unstore_unit]]], modifying unit.status.name directly, to avoid this, or if you are creating the unit, you can just add it to the unit's [status] tag in the [unit] tag. These are listed in [status], [[SingleUnitWML]].
** '''remove''': a list of status modifications to remove.
* {{anchor|apply_to-zoc|'''zoc'''}}: toggle the zone of control.
** '''value''': new value for zoc (boolean).
* {{anchor|apply_to-profile|'''profile'''}}: customize the profile of the unit. See [[UnitTypeWML]].
** '''portrait''': new image to display when the unit speaks.
** '''small_portrait''': new image to display in unit reports.
** '''description''': sets the text to display when hovering over the unit's type in the righthand pane.
** '''[special_note]''': {{DevFeature1.15|2}} Adds or removes a special note in the unit's description.
*** '''remove''': A boolean value specifying whether to add or remove a note. Defaults to '''no'''.
*** '''note''' (translatable): The text of the note you want to add or remove. If removing a note, this must be an exact match, character-for-character, for the note you want to remove, and must also be in the same textdomain.
*** Since the tag name is the same, notes can also be added using the standard special note macros, eg '''{NOTE_HEALS}'''.
*** To remove a note, you can simply suffix '''{NOTE_REMOVE}''' to the regular note macro, eg '''{NOTE_HEALS}{NOTE_REMOVE}'''.
* {{anchor|apply_to-new_ability|'''new_ability'''}}: Adds one or more abilities to a unit.
** '''[abilities]''': A subtag that contains the ability definitions.
* '''remove_ability''': Removes one or more abilities from a unit. Abilities are not reference counted. Adding twice and removing once still means the ability is gone.
** '''[abilities]''': A subtag that contains the ability definitions. Strictly speaking, all that is needed is the id= inside some tag. {{DevFeature1.17|17}} This is now deprecated, use [experimental_filter_ability] instead.
** {{DevFeature1.17|17}} '''[experimental_filter_ability]''': [[StandardAbilityFilter]] to match the abilities to remove.
* {{anchor|apply_to-new_animation|'''new_animation'''}}: contain animations that will be added to the unit, it can contain multiple animation blocks, and a single "id=" line. That Id should be unique for each effect block and is used by the engine to reuse WML parsing, making the loading faster. See [[AnimationWML]] for further reference.
* {{anchor|apply_to-image_mod|'''image_mod'''}}: modify the image path function ([[ImagePathFunctions]]) of all the unit's frames. Due to a bug, the effect is permanent even inside [object]duration=turn
** '''replace''': replaces the image path function(s) to be used, e.g. "RC(magenta>red)"
** '''add''': adds an image path function without removing any existing ones.
** If needed, you can also define new [[GameConfigWML#Color_Palettes|color palettes]] here.
* {{anchor|apply_to-ellipse|'''ellipse'''}}: Change the image used for the unit's ellipse.
** '''ellipse''' : the new image base path to use. Defaults to '''misc/ellipse'''. Can be set to '''none''' to disable the ellipse. An ellipse consist of a top and bottom part so by default in the simplest case the game will look for image files misc/ellipse-top.png and misc/ellipse-bottom.png. This can get further modified based on if the unit is a leader (can_recruit), does the unit emit a zone of control (ZoC) and/or is the unit selected. For a unit that is a leader, emits no ZoC and is currently selected the used files would then be misc/ellipse-leader-nozoc-selected-top.png and misc/ellipse-leader-nozoc-selected-bottom.png.
* {{anchor|apply_to-halp|'''halo'''}}: Change the image used for the unit's halo.
** '''halo''': the new image to use.
* {{anchor|apply_to-overlay|'''overlay'''}}: Change the unit's overlays.
**'''add''': the specified overlay will be added to the unit's overlays. It can be a comma separated list with multiple overlays. ''Note: overlays added in this way cannot be removed by [remove_unit_overlay] until the effect's duration is over.''
**'''replace''': all the unit's overlays will be removed and replaced with the specified one. Again, it can be a comma separated list. ''Note: overlays replaced in this way cannot be modified by [unit_overlay] or [remove_unit_overlay] until the effect's duration is over.''
**'''remove''': {{DevFeature1.15|0}} the specified overlay will be removed from the unit's overlays. It can be a comma separated list with multiple overlays.
** {{DevFeature1.15|0}} [unit_overlay] and [remove_unit_overlay] are now equivalent to adding a permanent object with this effect, after checking if the unit already has / already doesn't have the overlay (effects with temporary durations will cause false positives / false negatives in this check).
* {{anchor|apply_to-recall_cost|'''recall_cost'''}}: {{DevFeature1.13|2}} change a unit's recall cost
** '''set''': set recall cost to a specific value, or a percentage of original value
** '''increase''': alter recall cost relative to original value; can be positive or negative, or a percentage
* {{anchor|apply_to-alignment|'''alignment'''}}: {{DevFeature1.13|2}} change a unit's alignment
** '''set''': the new alignment (one of chaotic, lawful, neutral, liminal)
* {{anchor|apply_to-new_advancement|'''new_advancement'''}}: {{DevFeature1.13|2}} add new advancement choices to the unit
** '''replace''': whether to replace existing advancement choices; if this key is set to yes, existing advancement choices are cleared only if you're adding a choice of the same type. (That is, unit type advancements are cleared only if you're adding a new unit advancement choice, and AMLA choices are cleared only if you're adding new AMLA choices.)
** '''types''': a comma-separated list of additional unit types the unit can advance to. ('''Note:''' If using this, you probably want to include a filter to prevent the unit from being able to advance to this type once it has already done so.)
** '''[advancement]''': an advancement choice to add, see [[UnitTypeWML#After_max_level_advancement_(AMLA)|AMLAs]]; you can have several of these tags to add multiple advancement choices at the same time.
* {{anchor|apply_to-remove_advancement|'''remove_advancement'''}}: {{DevFeature1.13|2}} remove existing advancement choices from the unit
** '''types''': a list of unit type advancements to remove as a possibility
** '''amlas''': a list of AMLA id attributes; any advancement possibility with the given id will be removed
* {{anchor|apply_to-level|'''level'''}}: {{DevFeature1.17|15}} change a unit's level. '''Note:''' this key is incompatible with ''times=per level''; if this combination is used, the engine reports a warning and uses ''times=1'' as fallback value
** '''set''': set level to a specific value; can be positive or negative, but not a percentage
** '''increase''': alter level relative to original value; can be positive or negative, but not a percentage

== Movement and Vision ==

Wesnoth 1.14 introduced vision points; by default units have the same number of vision points as their max movement points. However, combining effects that change vision with effects that change movement had edge cases which were reworked in 1.16:

Consider a unit with 5 mp, and default vision:
* It has (effectively) 5 mp and 5 vp.
* After (mp + 1), it will have 6 mp and 6 vp.
* After (vp + 2), it will have 5 mp and 7 vp.

In 1.14, using an effect with apply_to=vision breaks the link between vision and movement:
* After (mp + 1) (vp + 2), it will have 6 mp and 8 vp.
* After (vp + 2) (mp + 1), it will have 6 mp and 7 vp.

{{DevFeature1.15|13}}, [effect]apply_to=movement has another attribute apply_to_vision, which defaults to true. With that change, the order that the effects are applied in doesn't matter:
* After (mp + 1) (vp + 2), it will have 6 mp and 8 vp.
* After (vp + 2) (mp + 1), it will have 6 mp and 8 vp.

Increasing movement by 50% increases vision by (50% of movement) not by (50% of vision). For a unit that started with 6 mp and 8 vp, the following effect would give it 9 mp and 11 vp.
[effect]
apply_to=movement
increase=50%
[/effect]

== Examples ==
=== Effect: apply_to = new_animation ===
This is the only way to change animations of units after they have been placed on the map.
In this example, I add very simple idle animation (taken from Goblin Spearman) to the unit, which moves to hex (x=1, y=5). If you want something more complex, you need to check [[AnimationWML]] page.

[event]
name = moveto
[filter]
x,y = 1,5
[/filter]
[object]
[filter]
x,y = 1,5
[/filter]
[effect]
apply_to = new_animation
[idle_anim]
{STANDARD_IDLE_FILTER}
start_time=0
[frame]
image="units/goblins/spearman-idle-[1~12].png:[150*3,300,150*8]"
[/frame]
[/idle_anim]
[/effect]
[/object]
[/event]

If you are going to use '''advanced WML''' and want to add animation to unit, stored in variable, then following example might help you. '''This way is not efficient if you have no additional logic like inventoriy, shops, advanced unit modifications in your add-on.''' Is is preferred to use first variant or define all needed animation in unit_type.
[event]
name = moveto
[filter]
x,y = 1,5
[/filter]
[store_unit]
[filter]
x,y=1,5
[/filter]
variable = stored_unit
[/store_unit]
[set_variables]
name = stored_unit.modifications.object
[value]
[effect]
apply_to = new_animation
[idle_anim]
{STANDARD_IDLE_FILTER}
start_time=0
[frame]
image="units/goblins/spearman-idle-[1~12].png:[150*3,300,150*8]"
[/frame]
[/idle_anim]
[/effect]
[/value]
[/set_variables]
[unstore_unit]
variable = stored_unit
[/unstore_unit]
[/event]

== Where to Use Effects ==

A collection of effects together makes up a "unit modification", which is encased in one of the three types of modification tags: '''[trait]''', '''[object]''', or '''[advancement]'''. Which tag to use depends on the goal of the modification.

* [[UnitsWML#.5Btrait.5D|Traits]] are shown in the unit details on the sidebar. They can be placed in a race or unit type to include the trait in the pool of random traits for that race or unit type, or they can be placed in the global [units] tag to add them to the global pool of random traits. (Note that this can cause out-of-sync errors in multiplayer.)
* [[UnitTypeWML#After_max_level_advancement_.28AMLA.29|Advancements]] are offered when a unit levels up. If a unit type has both modification advancements and regular advancements, the player can choose either each time they level up.
* [[DirectActionsWML#.5Bobject.5D|Objects]] are usually placed on the map or added by special events. They also have a built-in facility to automatically remove under certain conditions.

An effect can also be placed in '''[modify_unit]''' [[DirectActionsWML#.5Bmodify_unit.5D|ActionWML]] to apply it on-the-fly without keeping a record that it has been applied. This is mainly useful for effects that change transient properties such as current hitpoints or experience. An effect applied in this way is liable to be reverted when the unit is rebuilt in the future, for example when they level up or when an object is removed.

== See Also ==

* [[UnitTypeWML]]
* [[ReferenceWML]]
* [[AnimationWML]]

[[Category: WML Reference]]

StandardUnitFilter

2024-11-03T17:12:55Z

Newfrenchy83:

{{WML Tags}}

From [[FilterWML]], this is the standard way of filtering units.

When a unit filter is applied to a map, first it applies to all units on the field,
based on their coordinates.
Next it applies to units in the recall list.
This is important to remember as it means, for example,
that the tag '''[kill]''' can be used to kill units in the recall list.

You can access the filtered unit within the filter as the ''$this_unit'' variable, see [[SingleUnitWML]] for the possible content of these variables

The term [[StandardUnitFilter]] means that the set of such keys and tags (see below) can appear at that point. Often a [[StandardUnitFilter]] needs to be included in a [filter] tag. But many tags take the [[StandardUnitFilter]] directly as an argument, like [[DirectActionsWML#.5Bkill.5D|[kill]]] and [[ConditionalActionsWML#.5Bhave_unit.5D|[have_unit]]] (which each accept a few additional keys of their own). See [[Special:WhatLinksHere/StandardUnitFilter]] for tags which can contain a StandardUnitFilter.

__TOC__

The following attributes and sub-tags are allowed:

* '''id''': unit matches the given id. This is the same as ''id'' in the [unit] tag. Note that it is independent of a unit's user-visible name, which can be internationalized independent of this (see [[SingleUnitWML]]). id= can be a comma-separated list, every unit with one of these ids matches.
* '''speaker''': alias for id (no comma-separated list supported)
* '''type''': matches the unit's type name (can be a list of types)
* '''type_adv_tree''': {{DevFeature1.13|7}} matches the type name of the unit and all its advancements (can be a list)
* '''race''': the race of the unit type. This can be a comma-separated list; the unit's race must match one of the given races. Mainline races are listed in data/core/units.cfg 
* '''variation''': the unit type variation id (can be a list of variation ids)
* '''has_variation''': matches if the unit type for the unit defines at least one of the variation ids provided as a comma-separated list
* '''upkeep''': {{DevFeature1.15|3}} The upkeep of the unit. Can be either a non-negative number or one of the special values ''loyal'', ''free'', ''full''. Note that while ''loyal'' and ''free'' are synonymous with an upkeep of 0, the value ''full'' is not synonymous with any single numeric value – it is equivalent to <code>$this_unit.level</code>.
* '''ability''': unit has an ability with the given id; see [[AbilitiesWML]]. This can be a comma-separated list. The unit must have at least one of the specified abilities.
* '''ability_type''': {{DevFeature1.13|7}} unit has an ability with the given type (tag name) - eg, ''ability_type=heals'' will match a unit with any healing ability.
* '''ability_type_active''': {{DevFeature1.13|8}} unit has an ''active'' ability with the given type (tag name).
* '''ability_id_active''': {{DevFeature1.15|13}} unit has an ''active'' ability with the given id; see [[AbilitiesWML]]
* '''trait''': {{DevFeature1.13|8}} This can be a comma-separated list. The unit must have at least one of the specified traits.
* '''status''': {{DevFeature1.13|0}} matches if the unit has the specified status active. This can be a comma-separated list, in which case the unit will match as long as it has one of the listed statuses active (note: possible statuses are listed on the [[SingleUnitWML]] page).
* '''side''': the unit is on the given side (can be a list)
* '''has_weapon''': the unit has a weapon with the given name {{DevFeature1.13|5}} Now deprecated
* {{anchor|has_attack|'''[has_attack]'''}}: {{DevFeature1.13|5}} the unit has a weapon matching the [[StandardWeaponFilter]]. If this is present, '''has_weapon''' is ignored.
* '''canrecruit''': yes if the unit can recruit (i.e. is a leader)
* '''gender''': female if the unit is female rather than the default of male
* '''role''': the unit has been assigned the given role; see '''[role]''', [[InternalActionsWML]]
* '''level''': the level of the unit (this can be a comma-separated list).
* '''defense''': current defense of the unit on current tile (chance to hit %, like in movement type definitions)
* '''movement_cost''': current movement cost of the unit on current tile. Can be a number, range, or comma separated range.
* '''x,y''': the position of the unit. Note: As a special case '''x,y=recall,recall''' matches units on the recall list. Note that the similar '''search_recall_list=yes''' key is only available as part of the '''[have_unit]''' condition tag, and is not otherwise considered part of a StandardUnitFilter.
* '''find_in''': name of an array or container variable; if present, the unit will not match unless a unit with the same '''id''' is already stored in the variable
* {{anchor|filter_vision|'''[filter_vision]'''}}: this tests whether or not the unit is currently visible
** '''visible''': yes or no, default yes. When "yes", this matches units that are not obscured by fog or shroud, and that are not hiding (via the {{tag|AbilitiesWML|hides}} ability). When "no", this matches units that are obscured by fog or shroud, or that are hiding.
** [[StandardSideFilter]] tags and keys. Filter for who may be able to see (or not see) the unit. If there is *at least one* matching side which can see the unit then the filter matches, and otherwise it fails to match.
* {{anchor|filter_wml|'''[filter_wml]'''}}: Converts the unit to WML (as if by '''[store_unit]''') and tests it against a [[FilterWML#Filtering_on_WML_data|WML filter]]. For a list of things in the WML that could be filtered on, see [[SingleUnitWML]] or open a saved game in a text editor. Note that this is slower than other methods, so if possible it's better to use other filter keys and tags; however, if the WML filter contains only a child '''[variables]''', then the unit is not converted to WML and the filter is matched only against the unit's variables (which are already WML).
* '''[and]''': an extra unit filter. Unless the unit also matches the [and] filter, then it will not count as a match. ''Note: [and],[or], and [not] filters are considered after the containing filter; they are then processed in the order encountered.''
* '''[or]''': an extra unit filter. If a unit matches the [or] filter, then it will count as a match regardless of conditions in previous filters or the containing filter.
* '''[not]''': an extra unit filter. If a unit matches the [not] filter, then that unit will not be considered a match by the containing filter.
* {{anchor|filter_adjacent|'''[filter_adjacent]'''}} with a StandardUnitFilter as argument; do not use a [filter] tag. If present the correct number of adjacent units must match this filter.
**'''StandardUnitFilter''' tags and keys
** '''count''': a number, range, or comma separated range; default "1-6"
** '''adjacent''': a comma separated list of directions; default "n,ne,se,s,sw,nw" (see [[StandardLocationFilter#Directions|notes]])
** '''is_enemy''': a boolean specifying whether the adjacent unit must be an enemy or an ally (optional)
** '''$other_unit''': {{DevFeature1.13|2}} Within [filter_adjacent], the special variable $other_unit refers to the filtered unit from the enclosing filter, while $this_unit refers (as with all StandardUnitFilters) to the unit being filtered on.
* '''[filter_location]''': [[StandardLocationFilter]] - the tile that the unit is standing on matches the location filter.
*'''[filter_side]''': The currently filtered unit's side must match this [[StandardSideFilter]] for the unit to match.
**[[StandardSideFilter]] tags and keys
* '''formula''': A formula using [[Wesnoth Formula Language]]. The <tt>self</tt> variable is set to the current $this_unit, and the formula should return a boolean. If it returns 0, the filter does not match. Otherwise, the filter does match. {{DevFeature1.13|5}} If the filter has a secondary unit, the formula can access it using the <code>other</code> variable. Both the unit and the secondary unit are a '''unit object''', with keys documented [[#Wesnoth_Formula_Language|below]]. Do not surround the formula in <code>$(...)</code>, since that will erase the <tt>self</tt> variable.
* '''lua_function''': the name of a [[LuaWML|Lua]] function in the global environment that takes a unit as an argument and returns true if the given unit matches the filter. {{DevFeature1.13|5}} Non-global functions can now be used here by building a dot-separated "path". Note that this is not actually interpreted as Lua code even though it superficially resembles it, so using a Lua keyword in the path will work, for example "my_filter_functions.goto" will correctly use the function which in actual Lua code would need to be referenced as <code>my_filter_functions["goto"]</code>.
* {{anchor|filter_ability|'''[experimental_filter_ability]'''}}: {{DevFeature1.17|17}} [[StandardAbilityFilter]] matches if the unit has an ability with the given properties - eg, ''[experimental_filter_ability]affect_self=yes'' will match a unit with any ability with ''affect_self=yes''. {{DevFeature1.19|5}} [experimental_filter_ability] deprecated, use [filter_ability] instead.
* {{anchor|filter_ability_active|'''[experimental_filter_ability_active]'''}}: {{DevFeature1.17|17}} [[StandardAbilityFilter]] matches if the unit has an ''active'' ability with the given properties - eg, ''[experimental_filter_ability_active]affect_adjacent=yes'' will match a unit with any ''active'' ability with ''[affect_adjacent]''. The attributes checked are the same as for [experimental_filter_ability]. {{DevFeature1.19|5}} [experimental_filter_ability_active] deprecated, use [filter_ability] instead.
* '''[filter_ability]''': {{DevFeature1.19|5}} [[StandardAbilityFilter]] matches if the unit has anability with the given properties - eg, ''[filter_ability]affect_adjacent=yes'' will match a unit with any ability with ''[affect_adjacent]''.
** '''active''': if active=yes, matches if the unit has an ''active'' ability with the given properties, if active=no, matches if the unit has an ability with the given properties regardless of 'active' or not. '''active''' is false by default.

== [[Wesnoth Formula Language]] ==

When using the '''formula''' key, the '''self''' and (if present) '''other''' objects support the following keys:

* '''x''', '''y''', '''loc''' - the latter is a '''location object''' such as what would be returned from [[Wesnoth_Formula_Language#loc|loc()]].
* '''id'''
* '''type'''
* '''name'''
* '''usage'''
* '''canrecruit''', '''leader'''
* '''undead''' - true if the unit has the ''not_living'' status
* '''attacks''' - a list of '''[[FilterWML#Filtering_Weapons|weapon objects]]'''
* '''abilities''' - a list of the ability IDs the unit possesses
* '''hitpoints''', '''max_hitpoints'''
* '''experience''', '''max_experience'''
* '''moves''', '''max_moves'''
* '''attacks_left''', '''max_attacks'''
* '''level''', '''full''' - '''full''' refers to the unit's level to support the formula <syntaxhighlight lang=wfl inline>upkeep = full</syntaxhighlight>
* '''traits''' - a list of the trait IDs
* '''objects''' {{DevFeature1.19|0}} - a list of the objects IDs
* '''advancements_taken''' {{DevFeature1.19|0}} - a list of the advancements taken IDs
* '''traits_count''' {{DevFeature1.19|0}} - number of traits used by unit regardless of IDs
* '''objects_count''' {{DevFeature1.19|0}} - number of objects used by unit regardless of IDs
* '''advancements_taken_count''' {{DevFeature1.19|0}} - number of advancements taken used by unit regardless of IDs
* '''extra_recruit'''
* '''advances_to'''
* '''status''' - a list of active statuses
* '''side_number'''
* '''cost'''
* '''upkeep'''
* '''loyal''' - a constant 0 to support the formula <syntaxhighlight lang=wfl inline>upkeep = loyal</syntaxhighlight>
* '''hidden'''
* '''petrified''' - true if the unit has the '''petrified''' status
* '''resting'''
* '''role'''
* '''race'''
* '''gender'''
* '''variation'''
* '''zoc'''
* '''alignment'''
* '''facing'''
* '''resistance''', '''movement_cost''', '''vision_cost''', '''jamming_cost''', '''defense''' - {{DevFeature1.15|3}} Maps containing the basic movetype data. The '''defense''' and '''resistance''' maps contain the actual defense and resistance values, rather than the values specified in the WML, so you do not need to subtract them from 100.
* '''flying''' {{DevFeature1.15|3}}
* '''fearless''', '''healthy''' {{DevFeature1.19|4}}
* '''vars''' - WFL variables owned by the unit, which can be set and used by FormulaAI
* '''wml_vars''' - the WML variables stored in the unit
* '''n''', '''s''', '''ne''', '''se''', '''nw''', '''sw''', '''lawful''', '''chaotic''', '''neutral''', '''liminal''', '''male''', '''female''' - these are all defined to be the equivalent string so that, for example, you can write a formula like <syntaxhighlight lang=wfl inline>alignment = liminal and gender = female</syntaxhighlight> without needing to quote the alignment and gender strings.

== A Note about Re-Using the Same Attribute ==
You are limited to having each attribute, such as '''id''', appear once or less in a [[StandardUnitFilter]]. However, this can be worked around. If you have several specific units you want excepted from matching, use a separate [or] subfilters for each one. Also you can use [not] subfilters. For example to kill ([kill] uses the standard unit filter) all units except Gwiti Ha'atel and Tanar you can do the following:

<syntaxhighlight lang='wml'>
[kill]
[not]
id=Gwiti Ha'atel
[/not]
[not]
id=Tanar
[/not]
[/kill]
</syntaxhighlight>

And similarly if you wanted to kill both Gwiti Ha'atel and Tanar, but no one else you could do the following:

<syntaxhighlight lang='wml'>
[kill]
id=Gwiti Ha'atel
[or]
id=Tanar
[/or]
[/kill]
</syntaxhighlight>

== Tutorial ==

* [[FilterWML/Examples_-_How_to_use_Filter|How To Use Filter (with examples)]]

== See Also ==

* [[FilterWML]]
* [[ReferenceWML]]

[[Category: WML Reference]]

AbilitiesWML

2024-11-03T17:02:43Z

Newfrenchy83: /* Common keys and tags for every weapon special */

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_second]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_second]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''cumulative''': if set to 'yes', this ability will be cumulative with the base value for this ability. ''Beware of the bug with cumulative leadership in 1.16 https://github.com/wesnoth/wesnoth/issues/6466 , more info see below, in "Extra keys used by the ''leadership'' ability" section''. {{DevFeature1.17|5}}, bug fixed.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} Shortcut of [unit_type][event].

=== Extra keys used by the ''[heals]'' ability ===

* '''value''': the amount healed.
* '''poison''': can be one of ''slowed'',''cured''. ''slowed'' means poison will not take effect for adjacent units (it's not related to the weapon special "slows").

=== Extra keys used by the ''[regenerate]'' ability ===

* '''value''': the amount healed.
* '''poison''': can be one of ''slowed'',''cured''.

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* '''add''': adds to resistance. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': subtracts from resistance.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected. '''Replaces''' '''[filter_self]''' of normal weapon specials.
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker half of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50% by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special {{DevFeature1.17|23}} ===

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

FilterWML

2024-11-03T17:00:51Z

Newfrenchy83: /* Filtering Weapons */

{{WML Tags}}
== Filtering in WML ==

A ''filter'' is a special WML block.
Filters are used to describe a set of units, hexes, weapons or something else.
Filters are defined as matching something if all the keys in the filter match that thing.
For example, if a unit filter contains two keys,
a unit must match both of the keys in order to match the filter.

A StandardUnit(Location, Side, ...)Filter is the place where the set of such keys and tags can appear. A StandardFilter sometimes needs an according surrounding tag but often doesn't. It should be mentioned at the place in the wiki where it's said that you can use at a certain code position a StandardFilter whether you need a surrounding tag or not.

== Filtering Units ==

Filters are often used in action tags (see [[EventWML]]).
In this case the phrase "standard unit filter" is used in place of the set of standard keys.
Sometimes a filter is used to find the first unit that matches the filter;
for example, the '''[recall]''' tag recalls that unit.

Standard unit filters are also used in the tags '''[filter]''' and '''[filter_second]'''.
These are subtags of '''[event]''' which describe when the event should trigger.
Most event names (see [[EventWML]]) have units related to them called "primary unit" and "secondary unit".
In order for an event to be triggered, ''primary unit'' must match the filter contained in '''[filter]''',
and ''secondary unit'' must match the filter contained in '''[filter_second]'''.

See [[StandardUnitFilter]] for details.

== Filtering Locations ==

As you have seen, standard unit filter can contain a location filter.
Several actions, such as '''[terrain]''', also use location filters.
Location filters are represented on this site by the phrase "standard location filter".
A common use for location filters is to check the terrain of a space.

See [[StandardLocationFilter]] for details.

== Filtering Sides ==
Sometimes, it's needed to get a list of sides which satisfy certain criteria. For this, a side filter can be used.
Side filters are represented on this site by the phrase "standard side filter".

See [[StandardSideFilter]] for details.

== Filtering Weapons ==

Sometimes weapons/attacks are filtered on in WML. See also [[EventWML]], [[EffectWML]], [[AnimationWML]].

These keys are used as filter input for attack filters.

* '''range''': a range to filter
** '''melee''': only melee weapons pass
** '''ranged''': only ranged weapons pass
* '''name''': filter on the attack's name. See <code>data/units/</code> to find the name of a particular unit's attack.
* '''type''': filter on the attack's type. Values are 'blade', 'pierce', 'impact', 'fire', 'cold', and 'arcane' or customised type. {{DevFeature1.17|23}} [damage_type] can change the type of damage inflicted, and this change can be detected in the filter except when it is applied from a [damage_type] which affects the filtered attack, in this case only the type before any modification by a any [damage_type] will be detectable.
* '''damage''': filter on damage value. Can be a specific number or a list of ranges like 'damage=0-5,7-99'
* '''special_id''': {{DevFeature1.15|2}} Filter on a weapon special by id, for example, <code>magical</code> in <code>[chance_to_hit] id=magical</code>. True if the unit has the special, whether or not it's currently active.
* '''special_type''': {{DevFeature1.15|2}} Filter on a weapon special by tag name for example, <code>chance_to_hit</code> in <code>[chance_to_hit] id=magical</code>. True if the unit has the special, whether or not it's currently active. For values see [[AbilitiesWML]].
* '''special_id_active''': {{DevFeature1.15|2}} Like '''special_id''', but true if the special is active at the current location. Does not work in 1.16. {{DevFeature1.17|17}} Works again.
* '''special_type_active''': {{DevFeature1.15|2}} Like '''special_type''', but true if the special is active at the current location.
* '''special''': filter on the attack's special power, matches both id and tag name. {{DevFeature1.15|2}} Deprecated, see '''special_id''' and '''special_type''' instead.
* '''special_active''': {{DevFeature1.13|8}} Like '''special''', but true if the special is active at the current location. {{DevFeature1.15|2}} Deprecated, see '''special_id''' and '''special_type''' instead.
* '''[filter_special]''': {{DevFeature1.19|6}} Filter on a weapon special by using[[StandardAbilityFilter]]
** '''active''': if active=yes, true if the special is active at the current location. If active=no, true whether or not it's currently active, in this case, one special encoded in [attack] can be checked.
* '''number''': {{DevFeature1.13|5}} filter on number of strikes
* '''parry''': {{DevFeature1.13|5}} filter on parry value
* '''accuracy''': {{DevFeature1.13|5}} filter on accuracy value
* '''movement_used''': {{DevFeature1.13|5}} filter on attack's movement cost
* '''attacks_used''': {{DevFeature1.17|13}} filter on attack's attack cost
* '''min_range''': {{DevFeature1.19|4}} filter on attack's range (distance)
* '''max_range''': {{DevFeature1.19|4}} filter on attack's range (distance)
* '''formula''': {{DevFeature1.13|5}} filter using [[Wesnoth Formula Language]]. The context object for the formula is a '''weapon object''', which supports the following keys: '''name''', '''description''', '''type''', '''icon''', '''range''', '''damage''', '''number''', '''attack_weight''', '''defense_weight''', '''accuracy''', '''parry''', '''movement_used''', '''specials'''. The '''specials''' key is a list of all the special IDs the unit possesses. Do not surround the formula in <code>$(...)</code>, since that will erase the <tt>self</tt> variable. Keys supported after specific version: {{DevFeature1.17|13}} '''attacks_used'''. {{DevFeature1.19|4}} '''min_range''', '''max_range'''.

'''[and]''', '''[or]''', and '''[not]''' subfilters are also supported.

== Filtering Vision ==

The '''[filter_vision]''' tag allows you to filter units or locations based on whether or not the hex is obscured by fog or shroud from the point-of-view of a viewing side, and (in the case of units) whether or not the unit is hidden (via the {{tag|AbilitiesWML|hides}} ability).

* '''visible''':
** '''yes''' (default): matches when the location is not obscured by fog or shroud for the ''side'' and, when in a SUF, the unit is not hiding.
** '''no''': matches when the location is obscured by fog or shroud for the ''side'' or, when in a SUF, the unit is hiding.
* '''respect_fog''': yes or no, default yes. In a location filter (only), setting this to "no" will cause the test to ignore fog; it becomes a test for shrouded or not shrouded.
** When multiple viewing sides are listed, all of the sides must pass the visibility check in order for the [filter_vision] filter to return a successful match.
** When no viewing sides are listed, all enemy sides must pass the visibility check.
*'''[[StandardSideFilter]]''' tags and keys; all matching sides must be able to see the unit/location. If an empty filter, all sides (instead of only all enemy sides) match. If there is *at least one* matching side which can see the unit / location (accounting for fog / hiding / shroud) then the filter matches, and otherwise it fails to match.

'''Example:''' This event will fire when the enemy (side 2) moves to a location within the player's (side 1's) field of vision:
[event]
name=moveto
first_time_only=yes
[filter]
side=2
[filter_vision]
side=1
[/filter_vision]
[/filter]
[message]
speaker=unit
message="I am your enemy. I know that you can see me here."
[/message]
[/event]

'''Note:''' In a location filter, this tag is only useful when the viewing side is under a fog or shroud. You ''can'' set a shroud over an AI side. This will allow you to use the vision filter from the point-of-view of an AI side. The fog/shroud does not currently affect AI movement patterns, but the AI algorithm may become constrained by fog/shroud in the future.

== Filtering on WML data ==

Some places allow you to filter directly on WML data. WML filters are more free-form than other filters, allowing arbitrary WML data that is to be matched. Anything between '''<>''' needs to be replaced by the actual data to be filtered for. The following conventions are possible:

* '''<key>=<value>''': Means that the key '''key''' must be present with the specified '''value'''.
* '''glob_on_<key>=<glob>''': {{DevFeature1.15|0}} Means that the key '''key''' must be present with a value that matches the specified glob. In a glob, the '''*''' character matches any sequence of characters, while the '''?''' character matches any single character. In addition to the obvious, this is useful for matching the absence of a key - just place '''glob_on_<key>=*''' in a '''[not]''' tag.
* '''[<some_tag>]''': In a WML filter, all tags contain further WML filter data as children. The presence of a tag in the filter means that the WML must have at least one tag '''some_tag''' present, and at least one of the '''some_tag''' tags must match the WML filter contained in '''[some_tag]'''.
* '''[not]''': The WML filter contained in '''[not]''' ''must not'' match the WML.
* '''[and]''': {{DevFeature1.15|0}} In addition to the main filter, the filter contained in '''[and]''' must also match the WML. In most cases this tag is not necessary (the two filters can simply be merged), but in some unusual cases (particularly when globs are involved) it might be needed to get the desired result.
* '''[or]''': {{DevFeature1.15|0}} Adds another filter that is allowed to match in place of the main filter. Note that when combining several WML filters with '''[or]''' tags, the first filter must not be wrapped in '''[or]''' tags - doing so would mean that the first filter is actually an empty filter, which matches everything, meaning the other '''[or]''' tags are irrelevant.

== Tutorial ==
* [[FilterWML/Examples_-_How_to_use_Filter|How To Use Filter (with examples)]]

== See Also ==

* [[AnimationWML#Animation_Filtering|Animation filtering]]
* [[UnitTypeWML]]
* [[EventWML]]
* [[ReferenceWML]]
* [[FilterWML/Examples - How to use Filter]]

[[Category: WML Reference]]

AbilitiesWML

2024-11-03T16:53:30Z

Newfrenchy83: /* Common keys and tags for every weapon special */

{{WML Tags}}
== Abilities and their effects ==

There are two types of abilities: ones that apply to units (called ''abilities'') and ones that only apply when using a particular attack (called ''specials'' or ''weapon specials''). A unit may have multiple abilities and an attack can have multiple specials.

Each ability or special defines an effect based on one to three units. Most abilities apply to a single unit, and '''[filter_self]''' can be used to determine when the ability is active. Weapon specials apply to two units, which can be filtered either as "attacker" and "defender" (with the obvious meaning) or as "self" and "other" – the unit that possesses the special, and that unit's opponent. When filtering on the "other" unit, you use '''[filter_second]'''.

Leadership-style abilities are a more complex case, as they involve three units. Like a weapon special, there is an attacker and defender, but there is also a third unit that could be referred to as the "teacher". The "teacher" is the unit that possesses the ability, so it is referred to as "self" in the ability. A leadership ability works by temporarily granting a weapon special to either the attacker or the defender. The unit that benefits from this is referred to as the "student", while the unit that does not benefit is simply the "other" unit. When filtering on the "other" unit, you use '''[filter_second]'''.

== The ''[abilities]'' tag ==

The following tags are used to describe an ability in WML:

* '''[heals]''': modifies the hitpoints of a unit at the beginning of the healer's turn
* '''[regenerate]''': modifies the hitpoints of a unit at the beginning of the unit's turn
* '''[resistance]''': modifies the resistance of a unit to damage
* '''[leadership]''': modifies the damage of a unit
* '''[skirmisher]''': negates enemy zones of control
* '''[illuminates]''': modifies the time of day adjacent to the affected units
* '''[teleport]''': allows the unit to teleport
* '''[hides]''': renders the unit invisible to enemies
* {{DevFeature1.15|0}} All [[#The_.5Bspecials.5D_tag|weapon specials]] except for '''[plague]''', '''[heal_on_hit]''', and '''[swarm]''' can be placed in the '''[abilities]''' tag. These [[#Extra_tags_and_keys_used_by_weapon_specials_as_abilities|"weapon specials as abilities"]] will give the weapon special to all attacks the unit has.
* Any other tag is valid (for example '''[dummy]'''), but will result in an ability that does nothing but report it's there. '''Note:''' a dummy ability must have an id for the name and description to display.
* {{DevFeature1.15|3}} All the engine [[#The_.5Bspecials.5D_tag|weapon specials]] can be placed in the [abilities] tag now.

=== Available formula variables in Abilities and Weapon Specials ===

{{DevFeature1.15|?}} When using formulas in abilities and weapon specials, the following formula variables are available:
* '''self''': (unit) the unit that has the ability
* '''student''': (unit) for leadership-like abilities this is the unit that is adjacent to the unit that has the ability; if affect_self=yes, this is also unit who has ability.
* '''attacker''': (unit) for attack-related abilities and weapon specials, this is the attacking unit during the attack.
* '''defender''': (unit) for attack-related abilities and weapon specials, this is the defending unit during the attack.
* '''other''': (unit) the unit whose stats get modified from the ability. For abilities without 'apply_to=opponent' this is always the same as 'student'.

=== Common keys and tags for every ability ===

{{DevFeature1.13|?}} All keys inside any ability that expects a numeric value will also accept formulas using
[[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses. However, do '''not''' precede those parentheses with a dollar sign like <code>$(...)</code>, since that will erase the <tt>self</tt> variable.

* '''name''': the (translatable) name of the ability. If omitted, the ability will be a hidden ability.
* '''female_name''': the (translatable) name of the ability when possessed by a female unit. Defaults to ''name'' if not specified.
* '''name_inactive''': the (translatable) name of the ability when inactive. Defaults to ''name'' if not specified; if the ability is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''female_name_inactive''': the (translatable) name of the ability when inactive and possessed by a female unit. Defaults to ''name_inactive'' if not specified. You should thus set ''female_name'' as well!
* '''description''': the (translatable) description of the ability.
* '''description_inactive''': the (translatable) description of the ability when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''affect_self''': if equal to 'yes' (default), the ability will affect the unit that has it.
* '''affect_allies''': if equal to 'yes', the ability will affect units from the same and allied sides in the specified adjacent hexes. If set to 'no' it will not affect own or allied sides. If not set (default) it will affect units on the same side but not from allied sides.
* '''affect_enemies''': if equal to 'yes' (default is 'no'), the ability will affect enemies in the specified adjacent hexes.
* '''cumulative''': if set to 'yes', this ability will be cumulative with the base value for this ability. ''Beware of the bug with cumulative leadership in 1.16 https://github.com/wesnoth/wesnoth/issues/6466 , more info see below, in "Extra keys used by the ''leadership'' ability" section''. {{DevFeature1.17|5}}, bug fixed.
* '''id''': this ability will not be cumulative with other abilities using this id. Must be present if cumulative is anything other than 'yes'.
* '''halo_image''': {{DevFeature1.17|22}} if used, the halo specified showed on unit affected by ability.
* '''overlay_image''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit affected by ability.
* '''halo_image_self''': {{DevFeature1.17|22}} if used, the halo specified showed on unit who has ability when active.
* '''overlay_image_self''': {{DevFeature1.17|22}} if used, the overlay specified showed on unit who has ability when active.
* '''[filter]''': [[StandardUnitFilter]] If the unit owning the ability does not match this filter, the ability will be inactive.
* {{anchor|affect_adjacent|'''[affect_adjacent]'''}}: an adjacent unit that does not match this filter will not receive its effects. There can be multiple [affect_adjacent] tags in a single ability; a unit needs to match any one of these to receive the effects. The side requirement of matching units is defined by the '''affect_allies''' and '''affect_enemies''' keys. If there are no [affect_adjacent] tags, then no adjacent units will receive the effects.
** '''adjacent''': a comma separated list of any combination of these directions: '''n''','''ne''','''se''','''s''','''sw''','''nw'''. (See [[StandardLocationFilter#Directions|notes]])
** '''[filter]''': a [[StandardUnitFilter]]. {{DevFeature1.13|2}} The variable $other_unit refers to the unit owning the ability.
* '''[filter_self]''': if the owner of the ability does not match this filter, it will not receive the effects of the ability. [filter_self] takes a [[StandardUnitFilter]] as argument.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the ability will not be active and no-one will receive its affects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). In fact, it's really a shorthand for a [filter_adjacent] nested within [filter]. The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter][filter_location][filter_adjacent_location].
* {{anchor|filter_base_value|'''[filter_base_value]'''}}: filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', etc. If several keys are used all have to match.
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} Shortcut of [unit_type][event].

=== Extra keys used by the ''[heals]'' ability ===

* '''value''': the amount healed.
* '''poison''': can be one of ''slowed'',''cured''. ''slowed'' means poison will not take effect for adjacent units (it's not related to the weapon special "slows").

=== Extra keys used by the ''[regenerate]'' ability ===

* '''value''': the amount healed.
* '''poison''': can be one of ''slowed'',''cured''.

=== Extra keys and tags used by the ''[resistance]'' ability ===

* '''value''': set resistance to this value.
* '''max_value''': maximum resistance value. Default: 0%. {{DevFeature1.17|24}} Default: no limit.
* '''min_value''': {{DevFeature1.19|0}} minimum resistance value. Default: no limit.
* '''add''': adds to resistance. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': subtracts from resistance.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''apply_to''': a list of damage types; if left out, the ability applies to all types.
* '''active_on''': one of 'defense' or 'offense'; if left out, the ability is active on both.
These keys affect the actual resistance (e.g. -20%), not the damage modifier normally used in [resistance] (e.g. 120).
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the resistance ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[leadership]'' ability ===

* '''value''': the percentage bonus to damage.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
''Note:'' cumulative leadership with '''cumulative=yes''' and '''value=''' doesn't work in 1.16 (but fixed in 1.17.12 and later). To work around use '''add=''' or '''sub=''' key (it doesn't require cumulative) (https://github.com/wesnoth/wesnoth/issues/6466 ). If you want each instance of a ''[leadership]'' with the same id to be added you will be able to reuse '''cumulative=yes''' in 1.17.12 and later, otherwise, if you want to add the value of another ''[leadership]'' only once even with the same id in several copies, use '''add'''.
* '''[filter_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the owner of the ability uses a matching weapon.
* '''[filter_second_weapon]''': {{DevFeature1.15|0}} If present, the leadership ability only takes effect when the opponent uses a matching weapon.

=== Extra keys used by the ''[illuminates]'' ability ===

Because this ability changes the terrain instead of units on it, affect_self, affect_allies, affect_enemies and [filter_adjacent] have no effect.
* '''value''': the percentage bonus to lawful units. Units with '''alignment=lawful''' do +''value'' % damage when under the influence of a unit with this ability. Units with '''alignment=chaotic''' do -''value'' % damage. Units with '''alignment=neutral''' are unaffected by this ability. Units with '''alignment=liminal''' do -(abs(''value'')) % damage. ''value'' can be a negative number; this is useful if you want to give Chaotic units an advantage instead of Lawful ones.
* '''add''': the cumulative percentage bonus to damage. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the cumulative percentage bonus subtracted to damage.
* '''multiply''': multiplies resistance value.
* '''divide''': divides resistance value.
* '''max_value''': the maximum percentage bonus given. Cannot be less than 0. Defaults to 0 if not present.
* '''min_value''': the minimum percentage bonus given. Cannot be greater than 0. Defaults to 0 if not present.

=== Extra keys used by the ''[hides]'' ability ===

* '''alert''': the displayed text when the unit is discovered. Default "Ambushed!".

=== Extra tags used by the ''[teleport]'' ability ===

* '''[tunnel]''' - a [[DirectActionsWML#.5Btunnel.5D|tunnel tag]] (without the remove key) defining the tunneling source and target hexes, and maybe other conditions. (It automatically applies only to the unit with the ability.) You may use $teleport_unit inside the [tunnel][source] and [tunnel][target] tag for filtering purposes.

=== Extra tags and keys used by weapon specials as abilities ===

* {{anchor|filter_student|'''[filter_student]'''}}: {{DevFeature1.15|0}} If present, only the unit matching this filter, either the possessor of the ability if affect_self=yes, or an adjacent unit matching '''[filter_adjacent]''' will be affected. '''Replaces''' '''[filter_self]''' of normal weapon specials.
* '''overwrite_specials''': {{DevFeature1.15|13}} If present, allows a special abilities weapon with a numerical value to impose its value and ignore values of abilities or specials of the same type. If '''overwrite_specials=one_side''', the specials and abilities used by the opponent of the unit affected by the ability with this key and applied to it will not be affected. If '''overwrite_specials=both_sides''', all non-key-carrying abilities and all specials of the same type affecting the recipient unit will be affected, even if used by the opponent (used in the macro FORCE_CHANCE_TO_HIT).
* {{anchor|overwrite|'''[overwrite]'''}}: {{DevFeature1.17|22}} Part of '''overwrite_specials'''. Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** {{anchor|filter_specials|'''[experimental_filter_specials]'''}}: [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability].
* Other keys and tags appropriate to the specific weapon special.

=== Macros for common abilities ===

[https://www.wesnoth.org/macro-reference.html#file:abilities.cfg macro reference]
* ABILITY_AMBUSH
* ABILITY_CURES
* ABILITY_HEALS
* ABILITY_ILLUMINATES
* ABILITY_LEADERSHIP_LEVEL_1 to ABILITY_LEADERSHIP_LEVEL_5
* {{DevFeature1.13|2}} ABILITY_LEADERSHIP (replaces the above leadership macros, which are now deprecated)
* ABILITY_NIGHTSTALK
* ABILITY_REGENERATES
* ABILITY_SKIRMISHER
* ABILITY_STEADFAST
* ABILITY_SUBMERGE
* ABILITY_TELEPORT

== The ''[specials]'' tag ==

The '''[specials]''' tag goes inside the '''[attack]''' tag. It can contain the following tags:

* '''[attacks]''': modifies the number of attacks of a weapon, in using '''value''', '''add''', '''sub''', '''multiply''' or '''divide''' attributes
* '''[berserk]''': pushes the attack for more than one combat round, using '''value''' attribute, '''value''' is 1 by default
* '''[chance_to_hit]''': modifies the chance to hit of a weapon, using same standard numerical attributes as '''[attacks]'''
* '''[damage]''': modifies the damage of a weapon, using same attributes as '''[attacks]''' and '''[chance_to_hit]'''
* '''[damage_type]''' {{DevFeature1.17|23}}: changes the damage type of a weapon
* '''[disable]''': disables the weapon
* '''[drains]''': heals the attacker half of the damage dealt, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 50% by default
* '''[firststrike]''': forces the weapon to always strike first
* '''[heal_on_hit]''': heals the attacker when an attack connects, using same attributes as '''[attacks]''' and '''[chance_to_hit]''', '''value''' is 0 by default
* '''[petrifies]''': turns the target to stone
* '''[plague]''': when used to kill an enemy, a friendly unit takes its place
* '''[poison]''': poisons the target
* '''[slow]''': slows the target
* '''[swarm]''': number of strikes decreases as the unit loses hitpoints
Any other tag is valid, but will result in a special that does nothing but report it is there.

=== Common keys and tags for every weapon special ===

{{DevFeature1.13|?}} All keys inside any weapon special that expects a numeric value will also accept formulas using [[Wesnoth Formula Language]]. In order to use a formula in these keys, you must enclose it in parentheses.

* '''name''': the (translatable) name of the special. If omitted, the special will be hidden from the player.
* '''name_inactive''': the (translatable) name of the special when inactive. Defaults to ''name'' if not specified; if the special is supposed to be not displayed when inactive, you must explicitly set ''name_inactive'' to an empty string (nothing after the equals sign).
* '''description''': the (translatable) description of the special.
* '''description_inactive''': the (translatable) description of the special when inactive. Defaults to ''description'' if not specified.
* '''special_note''' {{DevFeature1.15|14}} Translatable string, which will be displayed in the unit’s help. See also [[UnitTypeWML#Special_Notes]].
* '''id''': this ability will not be cumulative with other specials using this id.
* '''active_on''': one of '''defense''' or '''offense'''; if left out, the special is active on both.
* '''apply_to''': one of '''self''','''opponent''','''attacker''','''defender''','''both''' (default: ''self''). Determines who the effects of this special are applied to.
* '''[filter_adjacent]''': if an adjacent unit does not match this filter, the special will not be active and no-one will receive its effects. Takes extra keys ''adjacent'', ''count'', ''is_enemy'', just like in a [[StandardUnitFilter]]. In fact, it's really a shorthand for a [filter_adjacent] nested within [filter_self], with the one difference that, in the absence of a specified ''count'', all listed directions must match (so, with two directiones eg ''adjacent=n,s'', the default is ''count=2''). The variables $this_unit and {{DevFeature1.13|2}} $other_unit both work as you'd expect. Multiple [filter_adjacent] can be provided, all of which must pass for the ability to activate.
* '''[filter_adjacent_location]''': like [filter_adjacent], but filters on locations instead of units. This is a shorthand for [filter_self][filter_location][filter_adjacent_location].
* {{anchor|filter_self|'''[filter_self]'''}}: the special will only be active if the owner matches this [[StandardUnitFilter]] (SUF).
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the opponent.
* {{anchor|filter_opponent|'''[filter_opponent]'''}}: the special will only be active if the opponent matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the unit that owns the weapon.
* {{anchor|filter_attacker|'''[filter_attacker]'''}}: the special will only be active if the attacker matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the defender.
* {{anchor|filter_defender|'''[filter_defender]'''}} the special will only be active if the defender matches this SUF.
** '''[filter_weapon]''': a [[FilterWML#Filtering_Weapons|standard weapon filter]], including special=.
** '''$other_unit''': {{DevFeature1.13|2}} The special variable $other_unit refers to the attacker.
* '''overwrite_specials''': if equal to 'one_side', then only this unit's specials are evaluated. If equal to 'both_sides', then both this unit's specials and any of the opponent's weapon specials that affect this unit are evaluated. If a special with this attribute is active, it will take precedence over any other specials of the same type that do not have this attribute. Don't applied to boolean weapon special like [poison] ,[slow], [firststrike] or [petrifies].
* '''[overwrite]''': {{DevFeature1.17|22}} Allows more flexibility in determining which specials should take priority over other specials of the same type.
** '''priority''': A numeric value to use when determining which special should be used if multiple specials of the same type have the '''overwrite_specials''' attribute. Default is 0.
** '''[experimental_filter_specials]''': [[StandardAbilityFilter]] Further attributes to filter specials by to determine if it should take priority over other specials. Accepts the same attributes as [experimental_filter_ability], {{DevFeature1.19|5}} [experimental_filter_specials] deprecated, use [filter_specials] instead
* '''[event]''': [[EventWML]]. {{DevFeature1.19|4}} Shortcut of [unit_type][event].

=== Common keys and tags for specials with a value ===

The '''[damage]''', '''[attacks]''', and '''[chance_to_hit]''' specials take values that specify how those specials modify their respective base values. The '''[drains]''' special takes a value specifying the percentage of damage drained (default 50) and '''[heal_on_hit]''' takes the amount to heal (default 0; negative values will harm the attacker, but not kill).

* '''value''': the value to be used.
* '''add''': the number to add to the base value. Note the interaction with '''sub''' in [[#Common_calculations]].
* '''sub''': the number to subtract from the base value.
* '''multiply''': this multiplies the base value.
* '''divide''': this divides the base value.
* '''cumulative''': if set to 'yes', this special will be cumulative with the base value.
* '''backstab''': if set to 'yes', this special will only apply to the attacker, and only when there is an enemy on the target's opposite side (i.e. when the standard backstab special applies). {{DevFeature1.13|2}} This is now deprecated. The same functionality can be achieved with a [filter_adjacent] in [filter_opponent]; see the implementation of the default backstab special for details.
* '''[filter_base_value]''': filters on the value before any modifications; uses the keys '''equals''', '''not_equals''', '''less_than''', '''greater_than''', '''less_than_equal_to''', '''greater_than_equal_to'''.

==== Common calculations ====

Several abilities and weapon specials take the keys '''add''', '''sub''', '''multiply''' and '''divide'''.

{{DevFeature1.19|4}} '''add''' and '''sub''' work independently.

Prior to 1.19.4:

* If '''add''' and '''sub''' are used in the same ability, the '''add''' is ignored
* If '''add''' and '''sub''' are used in separate abilities with the same id, or with the default id that's used when no id is specified, then the order in which the abilities are encountered controls the calculation, which may change depending on units' positions on the map.

=== Extra keys used by the ''[damage_type]'' special {{DevFeature1.17|23}} ===

* '''replacement_type''': replaces the attack type with the specified type when [damage_type] is active.
* '''alternative_type''': add a second type of attack to the existing type, it is always the one of the two which will do the most damage to the opponent which will be used.

'''Note:''' In 1.18, alternative_type may be stronger than expected, as the damage calculations sometimes ignore [resistance] abilities. This is a known bug, which occurs deterministically and will be left unfixed in 1.18.x to prevent Out Of Sync errors.

'''Note:''' If a [damage_type] special includes a [filter_weapon]type=, that filter is tested against the base type of the weapon, ignoring all [damage_type] specials.

=== Extra keys used by the ''[berserk]'' special ===

* '''value''': the maximum number of combat rounds (default 1).
* '''cumulative''': if set to 'yes', this special will be cumulative with other active berserk specials (on the current combatant, not with an opponent's berserk).

=== Extra keys used by the ''[plague]'' special ===

* '''type''': the unit type to be spawned on kill. When not specified, the default is the unit type of the unit doing the plaguing.

=== Extra keys used by the ''[swarm]'' special ===

* '''swarm_attacks_max''': the maximum number of attacks for the swarm. Defaults to the base number of attacks modified by any applicable [attacks] specials. If this is specified, then the base number of attacks is ignored.
* '''swarm_attacks_min''': the minimum number of attacks for the swarm. Defaults to zero. This can be set higher than swarm_attacks_max to cause a unit to gain attacks as health decreases.
The ratio of the unit's current to maximum hit points will be used to scale the number of attacks between these two values.

Prior to version 1.11, a [swarm] special will cause [attacks] specials to be ignored. In 1.11 and later, [attacks] specials are applied before [swarm].

=== Macros for common weapon specials ===

[https://www.wesnoth.org/macro-reference.html#file:weapon_specials.cfg macro reference]
* WEAPON_SPECIAL_BACKSTAB
* WEAPON_SPECIAL_BERSERK
* WEAPON_SPECIAL_CHARGE
* WEAPON_SPECIAL_DRAIN
* WEAPON_SPECIAL_FIRSTSTRIKE
* WEAPON_SPECIAL_MAGICAL
* WEAPON_SPECIAL_MARKSMAN
* WEAPON_SPECIAL_PLAGUE
* WEAPON_SPECIAL_PLAGUE_TYPE TYPE
* WEAPON_SPECIAL_POISON
* WEAPON_SPECIAL_SLOW
* WEAPON_SPECIAL_STONE
* WEAPON_SPECIAL_SWARM

== See Also ==

* [[UnitTypeWML]]
* [[SingleUnitWML]]
* [[ReferenceWML]]

[[Category:WML Reference]]

StandardAbilityFilter

2024-06-18T09:42:16Z

Newfrenchy83:

From [[FilterWML]], this is the experimental way to filtering ability inside [[StandardUnitFilter]] {{DevFeature1.17|17}}.

It is used to filter out abilities or special weapons using multiple attributes simultaneously (ability type, ID, but also if it affects adjacent units, etc.). The concept is still experimental and developers should keep in mind that it is still possible that it will be removed for stable version 1.20 if it is not validated in version 1.19.

The term [[StandardAbilityFilter]] means that the set of such keys and tags (see below) can appear at that point. Often a [[StandardAbilityFilter]] needs to be included in a [experimental_filter_ability] or [experimental_filter_ability_active],tag. In [overwrite] subtags in weapon specials [experimental_filter_specials] use also[[StandardAbilityFilter]].

The following attributes and sub-tags are allowed:

* '''tag_name''': matches with the specified ability types. If tag_name=heals then any ability [heals] will match.
* '''id''': unit has an ability with the given id. This can be a comma-separated list. The unit must have at least one of the specified abilities.
* '''affect_self''': matches abilities with ''affect_self'' having the specified value, this value is true by default in abilities.
* '''affect_enemies''': matches abilities with ''affect_enemies'' having the specified value, this value is false by default in abilities.
* '''affect_allies''': matches abilities with ''affect_allies'' having the specified value; however ''affect_alllies'' does not have a default value because its absence within an ability means that it only affects units on the same side as the possessor of it. So if ''affect_allies=none'' is checked, this will correspond to any ability not using this attribute.
* '''affect_adjacent''': match abilities with or without the [affect_adjacent] subtag. If the value is yes, matches abilities with this subtag.
* '''type''': specific to [plagues], match if the ability used as a weapon uses a matching type. If ''type=Walking Corpse'', any weapon transforming a killed unit into that unit type will match. Other abilities using ''type'' can also be checked.
* '''replacement_type''' {{DevFeature1.17|23}}: specific to [damage_type], match if the ability used as a weapon uses a matching type. If ''replacement_type=arcane'', any weapon who replace any type of damage by arcane will match.
* '''alternative_type''' {{DevFeature1.17|23}}: specific to [damage_type], match if the ability used as a weapon uses a matching type. If ''alternative_type=arcane'', any weapon who add arcane to type of damage will match.
* '''active_on''': for abilities used as weapons and [resistance], check if the unit is active in the specified situation. If ''active_on=defense'', then corresponds to active abilities only in defense. This attribute has the value ''both'' by default in these abilities.
* '''apply_to''': In special weapons, checks if the weapon applies to self, opponent, attacker and defender, ''apply_to=self'' by default. In resistance ''apply_to'' is used to determine the type of attack for which the resistance must be modified; it is not recommended to check an ability [resistance] with this attribute. {{DevFeature1.19|1}} It is modified to do an inclusion check for a comma-separated list of damage types in [resistance] abilities
* '''cumulative''': checks whether or not the cumulative option is used in abilities like [leadership] and all specials returning a numeric value.
* '''value''': if for example ''value=10-50'', all abilities with value between 10 and 50 will match, [drains] without specified value will also match, [leadership], [illuminates], [heals], [regenerate] and [heal_on_hit] have default value equals to 0, [berserk] has default value to 1 and [drains] an value by default to 50. Abilities without a default value like [teleport] or [hides] but also '[dummy]' abilities will not be able to match. {{DevFeature1.19|0}} If '''value=default''' and the ability does have a default value like [drains], then match if the value (specified or not) equals the default value.
* '''add, sub, multiply and divide''': as for value, match if the ability uses the specified attribute with the correct value. For add and sub, if ''add=10'' checked and an ability uses ''sub=-10'', it will match. Multiply and divide do not have this reversibility.
* '''overwrite_specials''': works with capabilities using this attribute with the option specified ''none'', ''one_side'' or ''both_sides''. If ''overwrite_specials=none'' is checked, abilities without overwrite_specials will match.
* '''[filter_wml]''' {{DevFeature1.19|0}}: Converts the ability to WML and tests it against a WML filter. Note that this is slower than other methods, so if possible it's better to use other filter keys; but it can be used to check sub-tags or keys that don't exist in [[StandardAbilityFilter]].

== See Also ==

* [[FilterWML]]
* [[AbilitiesWML]]

[[Category: WML Reference]]

StandardAbilityFilter

2024-06-18T09:41:13Z

Newfrenchy83:

From [[FilterWML]], this is the experimental way to filtering ability inside [[StandardUnitFilter]] {{DevFeature1.17|17}}.

It is used to filter out abilities or special weapons using multiple attributes simultaneously (ability type, ID, but also if it affects adjacent units, etc.). The concept is still experimental and developers should keep in mind that it is still possible that it will be removed for stable version 1.20 if it is not validated in version 1.19.

The term [[StandardAbilityFilter]] means that the set of such keys and tags (see below) can appear at that point. Often a [[StandardAbilityFilter]] needs to be included in a [experimental_filter_ability] or [experimental_filter_ability_active],tag. In [overwrite] subtags in weapon specials [experimental_filter_specials] use also[[StandardAbilityFilter]].

The following attributes and sub-tags are allowed:

* '''tag_name''': matches with the specified ability types. If tag_name=heals then any ability [heals] will match.
* '''id''': unit has an ability with the given id. This can be a comma-separated list. The unit must have at least one of the specified abilities.
* '''affect_self''': matches abilities with ''affect_self'' having the specified value, this value is true by default in abilities.
* '''affect_enemies''': matches abilities with ''affect_enemies'' having the specified value, this value is false by default in abilities.
* '''affect_allies''': matches abilities with ''affect_allies'' having the specified value; however ''affect_alllies'' does not have a default value because its absence within an ability means that it only affects units on the same side as the possessor of it. So if ''affect_allies=none'' is checked, this will correspond to any ability not using this attribute.
* '''affect_adjacent''': match abilities with or without the [affect_adjacent] subtag. If the value is yes, matches abilities with this subtag.
* '''type''': specific to [plagues], match if the ability used as a weapon uses a matching type. If ''type=Walking Corpse'', any weapon transforming a killed unit into that unit type will match. Other abilities using ''type'' can also be checked.
* '''replacement_type''' {{DevFeature1.17|23}}: specific to [damage_type], match if the ability used as a weapon uses a matching type. If ''replacement_type=arcane'', any weapon who replace any type of damage by arcane will match.
* '''alternative_type''' {{DevFeature1.17|23}}: specific to [damage_type], match if the ability used as a weapon uses a matching type. If ''alternative_type=arcane'', any weapon who add arcane to type of damage will match.
* '''active_on''': for abilities used as weapons and [resistance], check if the unit is active in the specified situation. If ''active_on=defense'', then corresponds to active abilities only in defense. This attribute has the value ''both'' by default in these abilities.
* '''apply_to''': In special weapons, checks if the weapon applies to self, opponent, attacker and defender, ''apply_to=self'' by default. In resistance ''apply_to'' is used to determine the type of attack for which the resistance must be modified; it is not recommended to check an ability [resistance] with this attribute. {{DevFeature1.17|23}} It is modified to do an inclusion check for a comma-separated list of damage types in [resistance] abilities
* '''cumulative''': checks whether or not the cumulative option is used in abilities like [leadership] and all specials returning a numeric value.
* '''value''': if for example ''value=10-50'', all abilities with value between 10 and 50 will match, [drains] without specified value will also match, [leadership], [illuminates], [heals], [regenerate] and [heal_on_hit] have default value equals to 0, [berserk] has default value to 1 and [drains] an value by default to 50. Abilities without a default value like [teleport] or [hides] but also '[dummy]' abilities will not be able to match. {{DevFeature1.19|0}} If '''value=default''' and the ability does have a default value like [drains], then match if the value (specified or not) equals the default value.
* '''add, sub, multiply and divide''': as for value, match if the ability uses the specified attribute with the correct value. For add and sub, if ''add=10'' checked and an ability uses ''sub=-10'', it will match. Multiply and divide do not have this reversibility.
* '''overwrite_specials''': works with capabilities using this attribute with the option specified ''none'', ''one_side'' or ''both_sides''. If ''overwrite_specials=none'' is checked, abilities without overwrite_specials will match.
* '''[filter_wml]''' {{DevFeature1.19|0}}: Converts the ability to WML and tests it against a WML filter. Note that this is slower than other methods, so if possible it's better to use other filter keys; but it can be used to check sub-tags or keys that don't exist in [[StandardAbilityFilter]].

== See Also ==

* [[FilterWML]]
* [[AbilitiesWML]]

[[Category: WML Reference]]