Dancing Hoskuld
Deity
The Great Mosque of Djenne is one, the Himeji Samurai Castle is another.
I also need to softcode the civic changes too.
Here's the list of new XML fields I have ATM: (There will be more)
CvBuildingInfos:
bRequiresHillsOrPeaksInVicinity
bFamous
bNotFamousCity
bRequiresDesert
iPillageGoldModifier
bNoEnemyPillagingIncome
BuildingProductionModifier
CvUnitInfos:
CivicProductionModifier
bRequiresStateReligionInCity
CvCivicInfos:
BuildingProductionModifier
CvTechInfo:
iUpgradeCostModifier
Edit: I went through all of RoM's python, and I think this is what I'm going to need to add.
Instead of bRequiresHillsOrPeaksInVicinity and bRequiresDesert you could go a bit more general and have prereqOrTerrains which lists a bunch of terrains. Naturally you would need a prereqAndTerrains also and if you wanted to go mad you could also go for terrain features

How would the iPillageGoldModifier interact with the unit plunder promotion?