Ashbane, The Adamantine Bone Render

Rejuvenation. After being destroyed, Ashbane gains a new body in 1d10 hours, with all its hit points.

Shadow Stealth. While in dim light or darkness, Ashbane can take the Hide action as a bonus action.

Legendary Resistance (3/Day). If Ashbane fails a saving throw, it can choose to succeed instead.

Adamantine Umbrage. A critical hit against Ashbane becomes as a normal hit.

Adamantine Gloom. While Ashbane is in dim light it gains a bonus of +2 to its AC and attack rolls. The bonus increases to +3 when Ashbane is in darkness.

Multiattack. Ashbane makes two claw attacks.

Piercing Claw. Melee Weapon Attack: +11 to hit, reach 15 ft., one target. Hit: 20 (3d10 + 4) piercing damage. If the target is a creature, Ashbane can pull the target up to 10 feet toward itself, and the target is grappled (escape DC 20). Ashbane has two claws. While a claw grapples a target, the claw can attack only that target.

Danse Macabre. If Ashbane is in dim light or darkness, each creature of Ashbanes’s choice within 5 feet of it must succeed on a DC 18 Constitution saving throw or take 34 (5d12 + 2) necrotic damage.

Ashbane then magically teleports up to 60 feet to an unoccupied space it can see. It can bring one creature it’s grappling, teleporting that creature to an unoccupied space it can see within 5 feet of its destination. The destination spaces of this teleportation must be in dim light or darkness.

(2 per turn)

How Bold. In response to a visible enemy moving into its reach, Ashbane makes one claw attack against that enemy. If the attack hits, Ashbane can make a second claw attack against the target.

Consequence. When Ashbane takes damage, it makes one attack with its claws against a random creature within its reach. If the attack hits, Ashbane can make a second claw attack against the target.

On Your Heels. If Ashbane is hit by a ranged attack, it magically teleports up to 60 feet toward its attacker.

(Ashbane has 3 legendary actions.)

Furor. Ashbane makes a claw attack.

Torment (2 Actions). Ashbane vanishes into a 10ft radius cloud of swarming moths and darkness centered on a creature Ashbane can see. The target creature must make a DC20 Wisdom save. If the target succeeds Ashbane makes one attack against the target creature. If the target fails the save, Ashbane makes 3 claw attacks from within the cloud before reforming in a space within the clouds area as it dissipates.

Desiccate (2 Actions). Ashbane pierces a target within 5 feet with its claws, forcing the target to make a DC 20 constitution save or take 11 (2d8 + 2) necrotic damage at the beginning of their turn for the next 3 rounds.