The new Black Crown Game Store is pedaling a hot new game and creating trouble for Grandpa Mutou’s family business. First a sinister clown-masked figure steals Yugi’s Millennium Puzzle, and then Ryuji Otogi, the teenage heir to the store, challenges Yugi to a collectible dice game of dragons and monsters. But without the Millennium Puzzle, Yugi can’t call on Yu-Gi-Oh! Trapped inside the Black Crown Game Store, Yugi must win a game of Dungeon Dice Monsters or lose the Millennium Puzzle forever.