Kraken

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.

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.

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.

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.

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.

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.