Is it possible to in some way limit the effects you get from a resource? Like for instance cows can only increase health in 5 cities each or you could only have 20 units requiring iron per iron source. I'm guessing not, since I don't see how, but I'm new to modding. Maybe you have some ingenious idea. The reason is that I've always disliked how having a single source of oil or iron can make or break a game. I like that resources are important and reasons to go to war over, but I think there should always be a reason to have more of a resource.