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 (2008) and the second game in the Left 4 Dead series, it was released for Microsoft 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 first-person shooter game developed and published by Valve.
