mr. bungle

[Metaltastic]

Dunno about Left 4 Dead, but he definitely was the voice of the eponymous demon thing in "The Darkness"

 

[GarethSE]

yeah he did the left 4 dead zombies
all the more reason not to buy either of those games >;D

 

[SwambA]

The monster sounds he did in I am legend are awesome! When Will Smith lays down in the bathtub the 1st night, and you hear all the monsters in the background slowly come in 1 by 1 till it reaches and cacophony of growls. That is freaky! A couple of times the screams scare the crap out of you!