Cover art.
The Nightmare Before Christmas: The Pumpkin King is a side-scrolling adventure game for the Game Boy Advance, released on the same day as The Nightmare Before Christmas: Oogie's Revenge, October 10, 2005.
The game takes place exactly one year before the events of The Nightmare Before Christmas, and explains how Jack Skellington met Oogie Boogie and how he became The Pumpkin King.
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