Jack O'Lantern is one of the antagonists of the children's television series, The Grim Adventures of Billy and Mandy. He is a minor player in the Non Disney Villains Tournament.
Non Disney Villains Tournament
Having stolen the Grim Reaper's scythe, Jack O'Lantern challenges Samhain for the title of the "embodiment of Halloween." He fires a flaming rock at Samhain with a slingshot, but his opponent effortlessly glides away. Jack O'Lantern gets smart and opens a portal of light, forcing the light-fearing Samhain to flee. Jack then summons an army of pumpkin monsters to help him eliminate Samhain. Samhain gathers a host of his own ghouls. These ghouls prove to be too much, cowering Jack into submission. The vengeful Samhain banishes Jack into the light, never to be seen again.
Cartoon Villains War
Vs Bill Chiper
Meanwhile, Bill Cipher, beginning the next phase of his plan, opened a portal into his home dimension, summoning two beings, Nergal and Jack O’Lantern. Bill had hoped to recruit them as henchmen in his schemes. Unfortunately, although Nergal seemed cooperative enough, Jack O'Lantern had his own plans, and intended on eliminating Bill and taking his place. Using a magic scythe, Jack summoned an army of pumpkin creatures, ordering them to destroy Cipher. Unimpressed, Bill easily obliterated Jack's minions, terrifying the pumpkin. Bill then banished Jack back to his own dimension, never to be seen again. Impressed by Bill's power, Nergal agreed to work with him, much to Bill's glee.