I've been trying to find a pattern for the one special resource you can get by mining plains, which to me is the most useful one: game. Everytime I start a new game, I save the game after the first turn, then play a quick game just to chart the territory and plan my occupation strategy (I try to make the most of my territory, and literally hate overlapping tiles), but sometimes knowing when a horse would appear could change the whole placement of my cities by rendering an inhospitable territory into an appealing one. I've tryied several predictive algorithms to see if they fitted with reality, but no success yet. It could just be random, yet I doubt it (map generation is one of the most reliable assets of teh game, the world is usually very balanced). Maybe someone more knowledgeable could give me a hint...