Left 4 Dead 2 is a single-player and multiplayer co-operative survival horror FPS game developed by Valve Corporation. It is the sequel to Left 4 Dead, it was first announced June 1st 2009 by Valve Corporation at Microsoft's E3 2009 press conference.
As of January 24, 2010, Metacritic gave Left 4 Dead 2 a metascore of 89 out of 100.
The Left 4 Dead 2 multiplayer demo was released on October 28th, for those who preordered. It was then made available to the public on November 3rd. 
The sequel picks up one week after the events of the first game (three weeks after the first infection) where The Infection has spread to the southern United States.  Left 4 Dead 2 introduces three new Special Infected, new weapons, melee weapons, new items, upgraded Infected, the Uncommon Common Infected, six new campaigns, and three new game modes: Scavenge Mode, Realism Mode, and Mutations which was released along with The Passing DLC.
The four Survivors the players control are Nick, Ellis, Rochelle, and Coach.
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