Bonespitter

Bony Body. A creature that starts its turn or enters a space within 5 feet of the bonespitter must succeed on a DC 18 Dexterity saving throw or take 16 (3d10) piercing damage.

Multiattack. The bonespitter makes two attacks: one with its bite and one with its bone spike.

Bite. Melee Weapon Attack: +13 to hit, reach 10 ft., one target. Hit: 21 (3d8 + 8) piercing damage. If the target is a Large or smaller creature, it must succeed on a DC 18 Dexterity saving throw or be swallowed by the bonespitter. A swallowed creature is blinded and restrained, it has total cover against attacks and other effects outside the bonespitter, and it takes 17 (5d6) acid damage at the start of each of the bonespitter's turns. An undead creature made of mostly bones, such as a skeleton, is immune to this acid damage. If the bonespitter takes 30 damage or more on a single turn from a creature inside it, the bonespitter must succeed on a DC 20 Constitution saving throw at the end of that turn or regurgitate all swallowed creatures, which fall prone in a space within 10 feet of the bonespitter. If the bonespitter dies, a swallowed creature is no longer restrained by it and can escape from the corpse by using 20 feet of movement, exiting prone.

Bone Spike. Ranged Weapon Attack: +13 to hit, range 30/120 ft., one target. Hit: 18 (3d6 + 8) piercing damage, and, if the target is a Large or smaller creature, it is knocked prone, pinned to the ground by the spike, and restrained. As an action, the restrained creature or a creature within 5 feet of it can make a DC 18 Strength check, removing the spike and ending the condition on a success. The spike can also be attacked and destroyed (AC 12; hp 15; vulnerability to bludgeoning damage; immunity to poison and psychic damage).

Shard Spray (Recharge 5-6). The bonespitter exhales a 60-foot cone of bone shards. Each creature in that area must make a DC 18 Dexterity saving throw, taking 35 (10d6) piercing damage on a failed save, or half as much on a successful one. If a Large or smaller creature fails this saving throw, it is also knocked prone, pinned to the ground by a shard, and restrained. As an action, the restrained creature or a creature within 5 feet of it can make a DC 18 Strength check, removing the shard and ending the condition on a success. The shard can also be attacked and destroyed (AC 12; hp 15; vulnerability to bludgeoning damage; immunity to poison and psychic damage).