Left 4 Dead 2 is the sequel to the best-selling and critically-acclaimed cooperative multiplayer smash from Valve, creators of the Half-Life, Portal, Team Fortress and Counter-Strike game properties. The title adds melee combat to the award-winning L4D style of play, with items such as a chainsaw, frying pan, axe, baseball bat, and more. Introducing the AI Director 2.0, L4D's dynamic gameplay is taken to the next level by giving the Director the ability to procedurally change weather effects, world objects, and pathways in addition to tailoring the enemy population, effects, and sounds to match the players' performance.
The result is a unique game session custom fitted to provide a satisfying and uniquely challenging experience each time the game is played. Finally, with new Survivors, boss zombies, weapons, and items, Left 4 Dead 2 offers a much larger game than the original with more co-operative campaigns, more Versus campaigns, maps for Survival mode at launch, and more.