- Crime. When I invaded an enemy city, I discovered a den of crime, with several autobuildings costing each more than 10
per turn (I'd say the total cost - before
% increase is taken into account - would probably be in the 50
); the total maintenance cost of the city was over 200
per turn for an income of 80
(though this was probably a bit reduced due to my invasion destroying some buildings). Unless invasion makes crime explode in some way, the AI cities must have thus an enormous strain due to crime; my guess is that the AI have difficulties managing it as well as the player, for example garrisoning town watchmen with policing promotions whenever the crime starts to be too high if there's no affordable building available to reduce crime instead.