Q323981

Left 4 Dead is a 2008 first-person shooter game developed by Valve South and published by Valve. It was originally released for Windows and Xbox 360 in November 2008 and for Mac OS X in October 2010, and is the first title in the Left 4 Dead series. Set during the aftermath of a zombie outbreak on the East Coast of the United States, the game pits its four protagonists, dubbed the "Survivors", against hordes of the infected.

Left 4 Dead uses Valve's proprietary Source engine, with four game modes: a single-player mode in which allied characters are controlled by AI, a four-player co-op campaign mode, an eight-player online versus mode, and a four-player survival mode. In all modes, an artificial intelligence dubbed the "Director" controls level pacing and item placements in an attempt to create a dynamic experience and increase replay value.