You command one of three classical civilizations ― Norse, Egyptian, and Greek ― and from each choose various patron gods as you advance ages to give you new units or bonuses depending on the dominion of the god. Step back from Empires II and embrace the mythic age. And please ignore the plot and writing - they took a screenplay excreted by Orson Scott Card and tried to run with it, but whoever was in charge of that buggered it up pretty badly. PC version recommended over XBOX version.
If you can get past the lack of polish, some bugs, unforgivably pretentious writing and the poor first half of the game, you can find a solid TPS (Translation: If you can get used to playing shitty games, you won't mind playing shitty games.) with very good balance and differentiation in the variety of 'powers' you accumulate. Mass Effect before Mass Effect, minus all but a few superficial RPG elements.