Sorry this is a week late, really.
Ensemble Backlog is a monthly gaming club created with the intent to clear the ever-mounting hordes of games that we accrue through Steam sales and bundles. If you don't have a problem with time management or impulse buys, this probably isn't for you.
February is Shadowgrounds month! Shadowgrounds is an isometric shooter in the vein of Alien Breed or Sigma Team's Shooter series. Mutants/aliens/monsters attack, and it's up to you to kill the hell out of them. Shadowgrounds features local co-op, but sadly there are no online options and it doesn't look like there ever will be. I don't think there's really much else to say!
I'm assuming that most of us got the Shadowgrounds series in the Frozenbyte Bundle from the Humble folks some time ago. If you don't already have the games, but want to join in and play with us anyways, there don't really seem to be any deals ongoing at this time. Gamersgate has a bundle with both games for £14.95/$20, or you can try to hunt around for physical copies at lower prices. The game seems to go on sale at steep discounts about once a month though, so it's probably worth holding off until you see a good deal.
As always, the rough timeframe to finish these games is one month, and I take it neither game is particularly long so even in February it shouldn't be too hard to finish by March 1.