Mastermind killer designing elaborate traps to test victims' will to live and teach them to appreciate life.
Jigsaw recruited and manipulated Hoffman to continue the games.
The final reveal identifies Hoffman as Jigsaw's other apprentice, and the microcassette warns him that he will face a test of his own.
Jigsaw uses Rigg's rescue instinct as the central subject of the game.
Rigg is kidnapped, given ninety minutes, and forced through several tests designed around his impulse to intervene.
Jigsaw keeps Eric alive as part of the timed final test.
Rigg is told that Eric is still alive, and Eric is later found restrained in the final room of the game.
Their failed marriage provides personal history behind the Jigsaw mythology.
Jill is explicitly identified as Jigsaw's ex-wife and is interrogated about her past with him.
Art is repeatedly used within Jigsaw's interconnected test structure.
Art is chained in the mausoleum and later appears in the final factory test alongside Eric and Hoffman.
Brenda's trap is part of Jigsaw's behavioral test for Rigg.
Brenda is placed in a trap that scalps her, and the setup manipulates Rigg into deciding whether to intervene.
Ivan's crimes are incorporated into a violent moral test.
Ivan is placed in a motel test that requires him to gouge out his own eyes before the trap dismembers him.
Kerry's death is tied to the wider Jigsaw apprentice mystery.
The police discover Kerry's remains, while the investigation concludes that Jigsaw's apprentice required assistance in her death.
Trevor is one of the victims used in the interconnected game.
Trevor is chained inside a mausoleum trap with his eyes sewn shut and is killed during the device's activation.
Explore the full interactive character relationship map of Saw IV
Related entry on Wikidata (Q1985548), public domain (CC0).