The story takes place in Heartland, where Yuma dreams of becoming the best Duel Monsters champion. During a duel with a school bully, Yuma receives unexpected help from Astral, a mysterious spirit. Astral confides in Yuma the mission to retrieve his vanished memories. He has materialized into 99 "Xyz Monster" cards known as "Numbers" and spread across the globe. But his cards have the power to corrupt their owners, revealing their darkest wishes. Yuma teams up with Astral to retrieve his memories and "Numbers."