RimCities is an attempt to create an interesting and unique end-game challenge for RimWorld players. This mod adds randomly generated cities to the world map, which are similar to other settlements but are far more difficult to attack. You may occasionally come across pirate-controlled cities, which provide even more of a challenge by occasionally bombarding you with mortar shells. As far as I have tested, RimCities is compatible with most of the currently popular RimWorld mods. Let me know if you find an incompatibility and we can try to find a solution.