to the person who was asking about gigantic maso, id say about 8 hours of RL time, but usually spanning 3-4 days. It would be cut in half if I didnt have to destroy all the worthless buildings the AI's build, as that takes up half my game time.
edit: getting in practice on smaller maps doesnt hurt either, since the strategies are nearly the same, just on a larger scale (learning to exploit the AI's weaknesses). Also, the process of giving an AI 1 influence point every turn is insanely powerful, and you can end up allied with all 5 AIs in a matter of minutes (going from wary all the way to close) if your having trouble getting them off your backs.
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