Abyss Squid

Amphibious. The squid can breathe both water and air.

Bone Meal. Any creature swallowed by the squid that has 0 Hit Points at the beginning of the squid's turn dies and is stripped of its flesh. If the squid finishes a Long Rest with the bones of a victim inside of it, the bones are dissolved and the squid has 50 Temporary Hit Points for the next week.

Multiattack. The squid makes three Tentacle attacks. It can replace one attack with a Bite attack, and can also replace an attack with a use of Toothy Maw.

Bite. Melee Attack Roll: +11, reach 5 ft., one creature Grappled by the squid. Hit: 16 (2d8 + 7) Piercing damage.

Tentacle. Melee Attack Roll: +11, reach 20 ft. Hit: 14 (2d6 + 7) Bludgeoning damage. If the target is a Huge or smaller creature, it has the Grappled condition (escape DC 16) from one of ten tentacles. A creature Grappled by the squid is also Restrained.

Toothy Maw. Constitution Saving Throw: DC 16, one creature swallowed by the squid. Failure: 23 (4d8+7) Acid damage, and the target is Stunned until the start of the squid's next turn. Success: Half damage only.

Swallow. Dexterity Saving Throw: DC 16, one creature hit by the squid’s Bite attack (the squid can have one creature swallowed at a time). Failure: The target is swallowed, and the Grappled condition ends. A swallowed creature has the Blinded and Restrained conditions and can’t teleport, it has Total Cover against attacks and other effects outside the squid.

If the squid takes 30 damage or more on a single turn from a creature inside it, the squid must succeed on a DC 21 Constitution saving throw at the end of that turn or regurgitate all swallowed creatures, each of which falls in a space within 10 feet of the squid and has the Prone condition. If the squid dies, any swallowed creature no longer has the Restrained condition and can escape from the corpse using 20 feet of movement, exiting Prone.