Scourge: Outbreak is today's XBLA title, and is available now. The developers behind the title, Tragnarion Studios, went out their way to deliver us a gameplay demo with developer commentary. You should check it out below.
In the game, players will help reveal the past of Echo Squadas well as participate in four-player co-op.
The game also includes PvP modes for up to eight players.
Scourge: Outbreak will run you 800 MS Points.