This guide is intended for version 1.11.6 and higher. A page about multiplayer campaigns in older versions can be found here.
Building Multiplayer Campaigns
The development version of Wesnoth has basic support for campaigns that can be played in multiplayer mode, with your friends, or even with an AI. There will still be some things that don't work as expected because some functionality for multiplayer campaigns is still being developed. While you can and should test your work in hotseat mode, there are a number of things that might behave differently under real network conditions (mostly affecting scenario and side parameters). Keep this in mind and make sure to test your campaign over the net, too. This page only documents the differences between writing multiplayer campaigns and single player campaigns, so you might want to read up on BuildingCampaigns and BuildingMultiplayer first.
The Campaign File
As of version 1.11.6, multiplayer campaigns do use [campaign] tag, thus allowing the same campaign to work both in singleplayer and multiplayer. The only difference is that game also checks for a couple optional tags when campaign is used in multiplayer. They could be found in CampaignWML page. Additionally, type attribute should be explicitly set to mp or hybrid or otherwise a campaign would not be visible in multiplayer.
The Scenario File
A scenario in a multiplayer campaign is almost identical to a scenario in a singleplayer campaign. You only need to change the following:
- Every scenario which should not be available to start directly, should have allow_new_game=no inside the [scenario] tag. This will prevent it from showing in entry points selection in multiplayer configuration screen.
- For scenarios that don't set allow_new_game=no, one could make use of new_game_title to have a custom title. This is useful if campaign is supposed to have multiple entry points. E.g. chapters.
- Each human-controlled side needs to have a controller=human key defined in their [side] tag to work in network mode.
- Each human-controlled side also needs to have a save_id defined inside their [side] tag. Each side's save_id should be unique, and it should be the same in every scenario. Without this, your recall lists and leaders will not carry over from one scenario to the next.
- If you want to carry over information for ai sides, they need to have a save_id defined and persistent=yes in their [side] tag.
- To ensure that your scenario settings would not get overwritten by the settings from the multiplayer configure dialog, set force_use_map_settings=true. However, if your campaign is not intended to be played strictly with default settings - set it to false.
- If any settings are still taken from the multiplayer configure dialog, it is possible to overwrite them in the prestart event. Useful tags include [set_recruit], [modify_side], [modify_turns] and [remove_shroud]. There is currently no way to remove fog. You might also want to use experience_modifier=100 in the [scenario] tag.