The Kraken is a notorious tentacled sea-monster of myth which serves Davy Jones as a sort of pet. When Jones has a debtor, he releases the kraken on them to drag them to the depths.
The Kraken is a gigantic cephalopod-like beast, with a squid-like mantle, a number of long, suckered tentacles at the base of its head. It also has a long, sharp tail similar to a squid and large round eyes with orange irises and black pupils. It had a large, maw-like mouth surrounded by fangs below its large eyes, and a massive body at least twice as long as its tentacles.
The overall length of the Kraken is similar to the length of ten ships, which would be approximately 1400 feet in total length. Its body resembles a massive, cuttlefish-like cephalopod.
The Kraken was a cryptid (animal of unconfirmed/mythical status) which was inspired by misidentifications of the animal now known as the Giant Squid. Due to the giant squids being beached or run into by ships, the kraken developed a reputation for attacking vessels. The name kraken did not originally refer to the giant squid cryptid but rather a monster from Norwegian sagas which is more comparable to a whale or carnivorous fish the size of an island.
The Kraken first appears as the pet of Davy Jones, the dark lord of the sea, and commanded to prey upon ships to ensure Jones had many unwilling candidates for service aboard his cursed vessel, the Flying Dutchman. The Kraken could be summoned from aboard the Flying Dutchman, with the use of a giant capstan hammer that sent a shock wave through the ocean that served as a call to the creature.
Captain Jack Sparrow was given a Black Spot by Bootstrap Bill Turner, on behalf of Davy Jones, and was forced to avoid the open water to escape the Kraken. When Jack's hat came into the possession of two men aboard a fishing boat, the Kraken followed, drawn to the piece of Jack. The creature then sank the ship with frightening ease, killing all on board. Later, when Will Turner escaped the Flying Dutchman with the key to the Dead Man's Chest, Davy Jones sent the beast to attack the ship Edinburgh Trader, that had rescued Will. The Kraken's attack killed most of the crew (the rest were executed by Jones' men under his orders) and sank the ship, forcing Will to stow away aboard the Dutchman once again until the ship had reached Isla Cruces. The Kraken then appeared again later, this time attacking the Black Pearl on Jones' orders when he failed to catch the ship. When the creature attacked, Will ordered the cannons fired on the Kraken's tentacles, severely wounding it but destroying the longboats in the process, save for the one Jack was escaping in. However, when the Kraken attacked again, it destroyed the cannons and attacked the crew, forcing Will, Elizabeth and the crew to set a trap for it using barrels of gunpowder and rum. This plan would have failed had Jack not returned and fired the shot that caused the explosion that burned the Kraken's tentacles and caused it to retreat, making it even angrier than before. Ultimately, however, Jack was forced into a confrontation with the beast due to being tricked and being chained to the mast of the Pearl by Elizabeth so that everyone else could escape, and was consumed by it aboard his ship, the Black Pearl as the Kraken pulled it down. Witnessing this, Jones stated that Sparrow's debt was paid.
Shortly after obtaining Davy Jones' heart, Cutler Beckett ordered Jones to kill the Kraken, fearing Jones may use it against him. The Kraken's death deeply affected Jones as well, as he was seen flinching at the mention of Beckett's recalling of the event. Upon returning from Davy Jones' Locker, Jack Sparrow and his companions discovered the dead beast washed up on a beach. Pintel and Ragetti approached the Kraken's face, and Pintel poked it with a long stick, celebrating the fact that the monster was dead and mused on calling themselves "Kraken Slayers" and turning the creature into an exhibit for profit. Recalling in silence that the Kraken had been the last of its kind, Jack reflected on his own mortality and the potential of being the last pirate in existence while looking into the beast's glazed eye and agreed that Beckett and Jones had to be stopped from taking control of the seas.
The Kraken appears in the game as part of the Pirates of the Caribbean set: in the storyline, the player has to obtain a prize which will allow them to fend off the Kraken and battle Davy Jones. The final reward of the game is the ability to summon the Kraken itself at will.
The Kraken appears as a boss fight in "The Caribbean" world, inserted into the game's adaptation of the events of At World's End. Unlike the film, it was still alive (indicating that Beckett didn't order its death in this version) and took part in the Battle of the Maelstrom.
A reference to the Kraken was installed to Pirates of the Caribbean circa 2006 with the refurbishment that incorporated in elements from the films. On the map of Isla Tesoro, red writing on the north-most part of the island reads, "Beware the Kraken". Given how the map gives it a good amount of proximity to the Ghostly Grotto, this could be implication that the kraken could have been responsible for some of the ship-wrecks seen on the island.
This map is only blatantly visible in Disneyland's incarnation of the attraction, being located on a sand-bar near a parrot in the queue. It is also present in the Magic Kingdom's albeit not visible, being in the possession of the pooped pirate and being spied on by Jack from a barrel.
The Kraken plays a more prominent role in this Shanghai Disney attraction. It is first seen when riders voyage under the ocean and see the Kraken swimming around and over them. Later in the ride it assists in Davy Jones' attack on Jack Sparrow and the guests.
It is stated in related media tied in with the films that the Kraken was the last of its kind.
While a famous sea cryptid, contrary to popular belief the Kraken did not have much affiliation with the golden age of piracy's superstition. This was largely because giant-squids (which inspired the kraken myth) were not native to tropical climates where the golden age of piracy was predominately set in.