One day, the townspeople couldn't take it anymore, devised a prank of their own, sent it to the queen (the queen had no sense of humor) and signed it from Jack. When the queen opened the gift from "Jack", she sent a knight out to kill him. The next day, the Grim Reaper went to reap his soul, but Jack stole his scythe and would only give it back if Grim had granted him immortality. When the deal was done, as punishment, Grim decapitated him.
Later on, Jack got himself a pumpkin and wore it as his new head. He still lived in his old house that was untouched by time and every Halloween Night, Jack emerged with a sack full of tricks and played terrible pranks on the people of Endsville.
Billy and Mandy's Jacked Up Halloween
While he was out Trick-or-Treating in Downtown Endsville, Billy ran up to Jack's old house and looked for candy. When Jack realized that Billy was carrying Grim's Scythe, he tricked Billy into giving it to him, brought demons from the Underworld to the surface world, and had them use pumpkins for bodies.
When Jack found Grim, he planned on using his Scythe to "return the favor," but Mandy tried to save Grim by devising pranks of her own only to be caught by Jack. Irwin instead was the victim of Mandy's pranks, which caused all of the possessed pumpkins to laugh themselves to death and Jack joined them all in the Underworld by a vortex, but he was still alive.
Video Game (GBA)
Jack served as the boss of Mandy's level Squash Quash. He summons pumpkins with his taunts.
- "Seriously, kids. There's nothing funny about meteors!"
- Jack is voiced by Wayne Knight (First appearance) and Maurice LaMarche (Other appearances).