Sat May 21, 2011 5:01 pm by lcalabrese
How about if you drop the city, it becomes owned by an NPC. It would create troops (and maybe traps/turrets) at a constant rate up to some maximum based on...the original civilization level of the player who dropped it? This way even if someone drops it, an attacker has the same chance of stealing it; it doesn't just disappear.
But the number of troops and such in it have to be a bit of a deterrent to just creating cities, upgrading them, dropping them, then farming easily - otherwise this would be abused. Granted it takes a long time or coins to upgrade a city to produce enough resources to be a useful farm, and the starter coins can't be abused this way because you have to be level 3 to get your first sub anyway.
Attacking goes the same as forts and oases - the attacker gets no pp for killed troops. If the loyalty goes down to zero it can be repossessed by the attacker, same as now.
Another suggestion is there could be some % chance that the NPC would upgrade some of the buildings in it. This is to give people a reason to go after some of these cities - you might get something good.