Jack Skellington introduces himself to Sora, Goofy, and Donald Duck as the ruler of Halloween Town. Jack plans to use the heart that Finklestein created to control the seemingly docile Heartless to make a festival called “Heartless Halloween” so that Halloween can be frightening, but the idea fails when not only the first experiment cause the Heartless to go berserk, but Oogie Boogie steals the finished heart, and plans to use it to take over Halloween Town. At Oogie’s manor, Jack, Sora, and the gang confront him. After Oogie is defeated, Jack finds out that Oogie uses dark orbs as his source of life, which Oogie tries himself with his manor to become a giant boss. Once the gang defeats Oogie once again, and his manor crumbles, revealing Halloween Town’s keyhole. Jack is short in this game than as he appeared in the movie, though he is still rather tall when compared to the game’s main protagonists.
“Created” from Sora’s memories of Halloween Town, when Jack Skellington wanted to ask Doctor Finkelstein what happened when he sniffs the potion that can bring “true memories”, Heartless appeared. When Jack Skellington had found out that Oogie Boogie had stolen the Doc’s potion, he must stop him before Oogie drinks the whole potion. They fail to reach him before he does, but they defeat him, as Oogie becomes overwhelmed with fear as a side effect of the potion. Sora becomes worried about what will happen when he discovers his true memories, but Jack reassures him that fear is a sign of a strong heart.