Updates to Left 4 Dead 2 have been released. The updates will be applied automatically when your Steam client is restarted. The major changes include:

Left 4 Dead 2
New mutation: Chainsaw Massacre
In Versus Special Infected bots spawn within 10 seconds of the Survivors leaving the safe room
Shortened spawn times for human Special Infected when the Infected team isn’t full. The time difference is added to the timer of the next bot in line to spawn
Exposed client console variable cl_viewmodelfovsurvivor to let players adjust their viewmodel FOV
To use this type cl_viewmodelfovsurvivor ## in the console. ## can be any number from 0-128 the default is 51
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