Thinking about what could be Civ5, I saw myself to want some kind of smooth representation of the nature. Among migrating animals. Then I thought: could this be a mod for Civ4? Like animal ressources aren't first attached to a tile anymore, until we capture and make a farm to pop up from them like a colony in Civ3 with a worker. Another reference to Civ3 is the slave workers that one could get from a winning battle with a special unit. (I think it was Maya but am unsure) So what about to put such a feature in Civ4, like when a hunter kill an animal, he gets a special one-use unit (worker-like) that would pop a farm up where he desires? What do you think?