Whereas “Age of Empires II” was set during the times between the Dark Ages and the Renaissance, “Age of Empires III” focuses on the times during the European colonization of America. Oh, don’t worry, there are still archers and siege weaponry ready to do your bidding, but you’ll also encounter units like musketeers and rockets that are completely new to the series. As such, the third game in the series does keep with the standard RTS formula, but it introduces some new concepts that give the game a lot more depth.