Shapechanger. The werekraken can use its action to polymorph into a kraken-humanoid hybrid or into a giant octopus, or back into its true form, which is humanoid. Its statistics, other than its size, are the same in each form. Any equipment it is wearing or carrying isn't transformed. It reverts to its true form if it dies.

Amphibious. The werekraken can breathe air and water.

Underwater Camouflage (Octopus or Hybrid Form Only). The werekraken has advantage on Dexterity (Stealth) checks made while underwater.

Multiattack (Hybrid Form Only). The werekraken makes two attacks with its harpoon or its tentacle.

Beak (Octopus Form Only). Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 1 piercing damage. If the target is a humanoid, it must succeed on a DC 11 Constitution saving throw or be cursed with werekraken lycanthropy.

Harpoon (Humanoid or Hybrid Form Only). Melee or Ranged Weapon Attack: +5 to hit, reach 5 ft. or range 20/60 ft., one target. Hit: 6 (1d6 + 3) piercing damage, or 7 (1d8 + 3) piercing damage if used with two hands to make a melee attack. If the attack was ranged and the target is the same size or smaller than the werekraken, the target must succeed on a DC 13 Strength saving throw or be pulled 15 feet closer to the werekraken.

Tentacle (Octopus or Hybrid Form Only). Melee Weapon Attack: +5 to hit, reach 10 ft., one target. Hit: 6 (1d6 + 3) bludgeoning damage, and the target must succeed on a DC 13 Strength saving throw or be pulled 5 feet closer to the werekraken and grappled (escape DC 13).

Ink Cloud (Octopus or Hybrid Form Only; Recharges after a Short or Long Rest). A 20-foot-radius cloud of ink extends all around the werekraken if it is underwater. The area is heavily obscured for 1 minute, although a significant current can disperse the ink. After releasing the ink, the werekraken can Dash as a bonus action.