"Of all the apocalypses that we've lived out in games and movies, none has been so disgusting as the one in The Last of Us. In it, the American population has been destroyed by an eerie (real-life) tropical fungus called cordyceps, which grows inside the body and turns people into shrieking, chomping, feral monsters. "Clickers" as they're called by survivors, are blinded by the fungal growths sprouting from their eyes, and track people down using sound, bouncing their "clicks" off of nearby walls in a similar way to bats.
"The first time you come across a dead one in the Outskirts level, it's slouched against a corridor, growing onto the wall. Joel, the battered survivor you play as, has to tread over to thing and literally peel it off the wallpaper, fungus and skin tearing away from it like a fleshy, picked mushroom. It's absolutely revolting and in-keeping with the game's squalid, jungly aesthetic."