Blue Gate Keys are required to Duel him at the Gate.
He appears in-game after the player reaches Stage 6 of Duel World (ZEXAL), at which point his Character Unlock Missions become available. Prior to April 23, 2021, he could only be unlocked through the special event Shark Attack: Numbers Appear!.
Also known as Shark for feasting on his opponents' decks, his high-level Dueling skills took him all the way to the Duel Nationals. But when he was disqualified, his Dueling took a darker path. His ace monster is "Number 32: Shark Drake".
When Shark wins a Duel against Yuma and Astral, he says "You think this is a joke Yuma?" followed by "If you'll reach the top of the game, you'll never win!" or "Come back when you're actually trying to win!"
When Shark loses a Duel against Yuma and Astral, he says "Looks like you're not as much of a loser as you used to be." or "You're happy is making me not happy!"