Dressed in a red boxer cloak, his face always covered with the infamous pig mask. He is a silent character whose main role is to assist Jigsaw in capturing victims and orchestrating their tests, such as with Tapp, whom he kidnaps and relocates at several points in the game, placing him in the Shotgun Collar, and also appearing to abduct Amanda (but this is all faked, since Amanda is already Jigsaw's apprentice). He is seen killing some test subjects, even when he is still working for Jigsaw who doesn't seem to take notice of the killings.
After Tapp completed all of his tests, Jigsaw revealed that Pighead sought to surpass him by sabotaging Tapp's test, so Tapp had to stop Pighead in order to get the key to the library.
At the end of the game, he is fought just before the final room (with the Freedom and Truth door), where he proves himself to be a formidable opponent, until tricked into being trapped and electrocuted to death by Tapp.
His true identity is a mystery, as Tapp did not bother to remove Pighead's mask after killing him.
He is referenced in an audio tape in Saw II: Flesh & Blood left by Tapp, who felt guilty for killing him, not knowing if he had a family or if he was forced to obey Jigsaw like all the others.
Tapp's tape: I killed a man in a pig mask back at Whitehurst. Nobody knows that but me. I never even knew who he was, just figured it was Jigsaw. I never even thought about it until I had to make the choice. Maybe he was a family man, maybe Jigsaw kidnapped his family. I would do the same thing if Michael was in danger. Even though he ruined my life, he's still my son.