Rome: Total war, is an RTS game focused on the Roman era, hence the name. Although a tiny bit unpopulated the Multilayer is addictive, choose any faction and upgrade your troops depending on how much money, aka Denarii, the 'host' of the game sets it to be. I believe its about $5 or $10 on Steam and there is a demo if you want to try it first.
Click here to see a remake of this battle on open terrain! www.youtube.com/watch
If you have any request's for battles send me a private message with what faction/units. Just in-case you dont know them here they are:
Greek City States (Spartans)