Chironex

Kurage is a Barian in the Yu-Gi-Oh! ZEXAL anime, belonging to the Fearsome Four of the Dark Dueling World. He is the self-proclaimed best WATER Duelist. Kurage means jellyfish in Japanese.

Personality
Kurage is arrogant, calling himself the greatest WATER Duelist. He also believes that the jellyfish is the greatest predator in the ocean.

Due to the aforementioned belief, Kurage prefers to be addressed as senpai (先輩; Senior in Japanese) and refers to his opponents as kōhai (後輩, junior in Japanese). When angered, Kurage's speech becomes extremely slurred.

Abilities
Kurage has the ability to turn to and from his original form, a jellyfish. With this, he can use his tentacles to poison his foes. He also has the ability to appear and disappear at will, as well as turn invisible. When walking, Kurage's footsteps generate a small amount of water.

Past life
Kurage was once the mentor of Mr. Heartland. An underworld Dueling criminal, he was involved in a car accident while fleeing from the police. The accident resulted in the deaths of him and the entire Kastle family. Kurage was eventually reincarnated as a Barian.

Legendary Number War
Kurage was one of the Fearsome Four of the Dark Dueling World. He was sent to Earth with the other members to gather the "Numbers" by Vector.

After Semimaru's defeat at the hands of Yuma Tsukumo and Trey, Vector ordered Mr. Heartland to send Kurage after Shark, as both were WATER Duelists. To this end, Kurage infiltrated the hospital where Shark's sister Rio was staying. He infected her with jellyfish poison in order to lure out Shark. He cornered him at his old house and infected him as well, wagering the antidote on a Duel and mused that Shark looked familiar. They were interrupted by Quattro, who joined the Duel on Shark's side, with Kurage having 8000 Life Points and both Shark and Quattro having 2000. Kurage brought out "Number 4: Stealth Kragen the Deadly Poisonous Jellyfish", inflicting 1600 damage to Shark. Quattro countered with "Number 15: Gimmick Puppet Giant Grinder". With aide of Quattro's "Angel Strings", Shark was able to defeat Kurage with "Number 73: Abyss Splash the Roaring Waterfall Deity". Quattro proceeded to take his "Number", while Kurage recalled that Shark was in the car that he crashed into years ago and then shockingly stated that since he was the only survivor, that Shark couldn't be standing before him right now.

Deck
Kurage uses a "Jellyfish-themed WATER" Deck, primarily focused on Swarm and Burn tactics, centered around "Number 4: Stealth Kragen the Deadly Poisonous Jellyfish".