Heroes VII

When a player modifies something on the map or adds something new, it isn't permanently embedded in the map itself. Instead, it's created as a separate data package that can be shared with the community and/or used in other maps. Consequently, any mod, whether it's a new faction, a set of neutral creatures, or something else, can be integrated into any map. The only issue to acknowledge is that it might be inconvenient for procedurally generated maps, as they would need to be manually adjusted if you really want to play with a mod. On one hand, this is inconvenient for large-scale mods, but on the other hand, it's very convenient for small modifications and creating good custom maps with custom content, for which you won't need to download additional material.