Boneturner

Aversion of Fire. If the Boneturner takes fire damage, it has disadvantage on attack rolls and ability checks until the end of its next turn.

Immutable Form. The Boneturner is immune to any spell or effect that would alter its form.

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

Magic Weapons. The Boneturner's weapon attacks are magical.

Boneturning. The Boneturner may, as an action on it's turn, reach into the body of an incapacitated creature and pluck out it's bones and add them to it's form. If the creature has bones and is alive it suffers 15 (2d10+4) necrotic damage and it's max HP is reduced by half the amount rolled. Whether the target is alive or dead the Boneturner heals for half the amount rolled.

A creature affected by boneturning can return one recovered bone per casting of lesser restoration. If the bones are not recovered, greater restoration can replace one bone per casting. Regeneration or Wish can restore all bones at once. The creature's max HP is returned to normal once all bones are returned or if remove curse is cast on the creature.

Multiattack. The Boneturner makes two claw attacks.

Claw. Melee Weapon Attack: +7 to hit, reach 10 ft., one target. Hit: 13 (2d8 + 4) slashing damage.

Boneturning. Melee Weapon Attack: +7 to hit, reach 10 ft., one target that has bones and is incapacitated. Hit: 15 (2d10+4) necrotic damage. Heal half the amount.

Dis-Arm. When targeted by a melee attack the Boneturner may, as a reaction, impose disadvantage on the attack. If the attack misses the target is grappled as the Boneturner's form warps around and siezes the limb of the attacker. If the attacker ends it's turn while still grappled in this way it is immediately subjected to the Boneturning attack, ignoring the incapacitated requirement. The Boneturner may not use this ability again until the attacker breaks free.