Alien Swarm: Gameplay HD This game is powered by Valve and the Source Engine and is available free of charge here : http://store.steampowered.com/app/630/ Release Date: 19 Jul 2010 Song : buy it here http://www.amazon.co.uk/Self-Vs-Feat-...
FYI : Alien Swarm was first of all a mod for UT2K4 and was adapted to the source engine by a group of talented designers at Valve who were hired from the Mod community. Official website :
