An epic bug hunt featuring a unique blend of co-op play and squad-level tactics. With your friends, form a squad of four distinct IAF Marine classes. Plan your attack using an unlockable arsenal of weapons with countless loadout configurations against a wide variety of aliens. Blaze your way through an overrun, off-world colony, eradicating the alien infestation in environments ranging from the icy planet's surface, to a subterranean lava-flooded mining facility.

DmitriyT says

10/10 - Agree (3) Disagree (1)

Free. Sci-fi. Multiplayer coop. Source Engine. This mix makes the game very fun to play and provides breathtaking experience. Beautiful graphics. However it lacks new levels and campaigns, inspite of community have provided about 53 playable campaigns.