The Two Leons - S3.E51

Leon and Takuto enter Tatsunagi HQ and confront Reversed Takuto, who sends Leon away and traps Takuto in black rings. Leon is transported to another room where he encounters his Reversed future self. The two Leons then fight each other, and the Reversed Leon eventually uses Blue Storm Karma Dragon, Maelstrom "Яeverse". Along with its powerful Limit Break, Reversed Leon puts an enormous amount of pressure on Leon while also retiring his rear-guards, leaving him with almost nothing. Against all odds, Leon uses Tetra-drive Dragon to defeat his Reversed self, who disappears after the long battle. Leon is left fatigued and is transported back to the original room where Takuto, freed from his bindings, challenges his Reversed self to a cardfight.