Left 4 Dead 2 builds upon cooperatively focused gameplay and Valve's proprietary Source engine, the same game engine used in the original Left 4 Dead. The sequel to Turtle Rock Studios's Left 4 Dead, it was released for Windows and Xbox 360 in November 2009, Mac OS X in October 2010, and Linux in July 2013. Left 4 Dead 2 is a 2009 multiplayer survival horror first-person shooter developed and published by Valve.
