http://store.steampowered.com/app/1250/Killing_Floor/ Killing Floor is a Co-op Survival Horror FPS set in the devastated cities and countryside of England after a series of cloning experiments for the military goes horribly wrong. You and your friends are members of the military dropped into these locations with a simple mission: Survive long enough to cleanse the area of the failed experiments!
How to activate a Steam code 1. Run Steam (if you have not, then you can download it here: http://steampowered.com/download/SteamInstall.msi 2. Log. 3. In the top menu, choose the Games -> Activate via Steam. 4. accept the agreement and enter the code. 5. Proceed further in the instructions and download the game activated. Steam Trading Cards - YES?