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Map Painter: campaign map editing with www.nopeace.net

With this mod, you can edit region ownership using
https://www.nopeace.net/ (made by IMRZ/Bombardier)
and then load that edited map ingame when starting a new campaign.

In the web application switch to Planner using the button in the bottom left. Make your edits to the map, and then click on Export (inside the faction select screen, second button in the bottom left). Your browser should download a "map.json" file. Put that file inside the "steamapps\common\Total War WARHAMMER III" folder.
Then once you start a new campaign use the button on the top left (see screenshot) to load that map.

I added an "export map" command to my Console Commands mod, so you can now upload your ingame map state into the app. "export map" console command will create a map_out.json in your WH3 Steam folder.
You can also use the "show mp" command to show this mod's button whenever you want.

Works on both Immoral Empires and RoC map. And note that although the app lists all factions on both maps, some factions are campaign-specific.
If you take away a region from a faction any armies of that faction in that region get moved to another region they own. So move your armies into regions you own before changing the map, or they'll stay in place.
If a faction doesn't own any regions at all their armies get deleted.
Giving regions to horde factions won't work.

Script mod = compatible with everything. Should work in MP (both players need to put the same map.json file inside their WH3 folder) but it's possible the PCs can desync during the process because it's very computationally expensive. (A comment said it desynced for them but that they could share the save file between themselves after the map was changed.)

Check out my other mods.
Thanks to IMRZ/Bombardier for making the https://www.nopeace.net/, it's not mine.

If you can't see the button ingame when you start a new campaign the most likely cause is your ingame scripts are broken because some other mod you have has a script error and that makes other script mods stop working as well. Try this mod by itself to make sure.

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