Titanic Kraken

Immortal Nature. The kraken doesnt require air, sustenance, or sleep.

Legendary Resistance (3/Day). If the kraken fails a saving throw, it can choose to succeed instead. When it does so, it can use its reaction, if available, to attack with its tentacle.

Magic Resistance. The kraken has advantage on saving throws against spells and magical effects.

Siege Monster. The kraken deals double damage to objects and structures.

Bloodied Ichor. While the Kraken is bloodied and in the water, black ichor leaks from it in a 60-foot radius, spreading around corners but not leaving the water. The area is lightly obscured to all creatures except the Kraken. A creature that starts its turn in the area takes 10 (3d6) acid damage.

Bite. Melee Weapon Attack: +18 to hit, reach 5 ft., one target. Hit: 36 (4d12 + 10) piercing damage. If the target is a Huge or smaller creature grappled by the kraken the target is swallowed. A swallowed creature is blinded and restrained its Speed is 0 it has total cover from attacks from outside the kraken and it takes 42 (12d6) acid damage at the start of each of the krakens turns.

If a swallowed creature deals 50 or more damage to the kraken in a single turn, or if the kraken dies, the kraken vomits up the creature.

Ink Cloud. While underwater the kraken exudes a cloud of ink in a 90-foot-radius sphere. The ink extends around corners and the area is heavily obscured until the end of the krakens next turn or until a strong current dissipates the cloud. Each non-kraken creature in the area when the cloud appears makes a DC 24 Constitution saving throw. On a failure it takes 27 (5d10) poison damage and is poisoned for 1 minute. On a success it takes half damage. A poisoned creature can repeat the saving throw at the end of each of its turns. ending the effect on a success.

Summon Storm (1/Day). Over the next 10 minutes storm clouds magically gather. At the end of 10 minutes a storm rages for 1 hour in a 5-mile radius.

Lightning (Recharge 5-6). If the kraken is outside and the weather is stormy three lightning bolts crack down from the sky each of which strikes a different target within 120 feet of the kraken. A target makes a DC 24 Dexterity saving throw taking 28 (8d6) lightning damage or half damage on a save.

Tentacle. Melee Weapon Attack: +18 to hit, reach 30 ft., one target. Hit: 28 (4d8 + 10) bludgeoning damage and the target is grappled (escape DC 26). Until this grapple ends the target is restrained. A tentacle can be targeted individually by an attack. It shares the krakens hit points but if 30 damage is dealt to the tentacle it releases a creature it is grappling. The kraken can grapple up to 10 creatures.

Fling. One Large or smaller object or creature grappled by the kraken is thrown up to 60 feet in a straight line. The target lands prone and takes 21 (6d6) bludgeoning damage. If the kraken throws the target at another creature that creature makes a DC 26 saving throw taking the same damage on a failure.

The kraken can take 3 legendary actions. Only one legendary action can be used at a time and only at the end of another creatures turn. It regains spent legendary actions at the start of its turn.

Tentacle. The kraken makes one tentacle attack.

Fling. The kraken uses Fling.

Squeeze (Costs 2 Actions). The kraken ends any magical effect that is restraining it or reducing its movement and then swims up to half its swim speed without provoking opportunity attacks. During this movement, it can fit through gaps as narrow as 10 feet wide without squeezing.