It's a lot like risk although it's open source for maps and gametypes so it gets pretty complex. Pretty sweet online real time games but I suggest playing at least the first 3 single player maps to get the hang of the strategy etc. Theres some crazy epic maps on here that make for awesome (but long games). My favorite is Big U.S. where you are basically playing in teams to control the entire United States...it pretty much has a territory on a county level state by state...
It can get pretty arduous in some games though so pick game type depending on how long you have to play.
