Zombies are big business these days. Woody Harrelson is fighting with them, everyone seems to be convinced that they are the just-over-the-horizon harbingers of the end of the world, even Mel Brooks' son is making a career out of explaining how to survive the coming onslaught of shuffling, mindless, brain-hungry animated corpses. But gamers have been battling zombies for far longer, much before the mainstream picked them up as the villain du jour. When the Resident Evil series turned its focus from the undead to foreign lands and infected villages, it took a few years before a new zombie game benchmark came along. 2008's Left 4 Dead filled the hole rather nicely, but with a totally different style of gameplay from the tank controls and mind-deficient zombies of yore.