As Yuma and Shark are hospitalized following their fall, Yuma becomes downhearted about his duel with Mizar. Irritated by his behavior, Shark decides to steal Yuma's key to lure him into a duel. Shark instantly brings out both Aero Shark and Black Ray Lancer, dealing a lot of damage to Yuma. Insulted by Yuma's defensive play, Shark brings out Shark Fortress to break through Yuma's defenses. As Shark makes his final attack, Yuma's wishes to keep dueling with Astral brings him to his side, giving Yuma the tactics to turn the duel around, summoning out Heroic Champion - Excalibur and winning the duel with its abilities. (thetvdb.com)