An online cooperative survival horror experience explicitly designed to emphasize extreme teamwork and intense action. A small group of four “ Survivors ” must fight their way through apocalyptic environments in an attempt to escape the overwhelming hordes of dangerous “ Infected ” – violently psychopathic victims of a horrible viral pandemic. Built upon the latest version of Valve ' s Source Engine and driven by Turtle Rock Studio ' s own next-generation AI technology, the resulting dramatic experience never plays exactly the same way twice. Left 4 Dead will be available on the PC and the XBox 360 in 2008.