I call this "Strategy Arena".
Imagine DotA with armies instead of heroes. You farm minerals and vespene instead of creeps. This means instant action team battle - a few click macro and lots of micro game. It is fast and epic. You dont build any structures. You can build unique boss units.
All three races and computer players of all levels available. So you can play 1v1, 2v2, 3v3 or single player or coop against attack waves.