Surume

The kraken (クラーケン) is a sea monster which dwells in the deepest parts of the ocean.

Appearance
The kraken is massive boneless octopus-like creature several hundred times larger than the Thousand Sunny. Unlike a regular octopus, it has a turtle-like head with a beak between the arms.

Personality
In Norse mythology, the kraken is said to have dragged dozens of sailing vessels down into the ocean to devour its crew. Indeed, when the Straw Hats first encounter one on their way to Fishman Island, several crushed pirate ships can be seen between its massive tentacles, indicating that it feeds on the ships and crew it pulls down into the ocean. Caribou recites a story about it, calling it "the enemy of the human race" and that it "never knows satisfaction where killing is concerned." He found it odd that one would be living near the Red Line.

History
The Straw Hat Pirates first encountered a Kraken on their way to Fishman Island. The massive creature apparently had taken shelter beneath the Downward Plume while feeding off of the passing pirate ships attempting to make their way through the Red Line for the past few days. Several crushed ships can been seen clutched between its tentacles. While the rest of the crew comments on the creature's sheer gargantuan size, Luffy, undeterred, expresses his wish to "tame the little guy" with excitement, much to Caribou's shock. Soon Coribou and the other Caribou pirates arrive and the Kraken destroys their ship.

Luffy, Sanji, and Zoro left the Sunny in Barefoot Coating bubbles introduced by Caribou in order to fight the Kraken without bursting the protective bubble around the Sunny. Sanji burned one of the Kraken's arms off with Diable Jambe, followed with Zoro severing three more with a new Santōryū technique. This infuriated Luffy due to his desire tame the Kraken as a pet. Luffy then used Gear Third and imbued the attack with Busoshoku Haki. The attack knocked out the Kraken even while Luffy was being severely weakened by the seawater. The Kraken then plummeted towards the blackest depths of the sea along with the trio.