Count Zevok

Ring of Spell Turning. While wearing this ring, Zevok has Advantage on saving throws against spells. If he succeeds on the save for a spell of level 7 or lower, the spell has no effect on him. If that spell targeted only him and didn’t create an area of effect, he can take a Reaction to deflect the spell back at the spell’s caster; the caster must make a saving throw against the spell using their own spell save DC.

Stake to the Heart. Zevok is destroyed if a weapon that deals Piercing damage is driven into his heart while he has the Incapacitated condition.

Multiattack Zevok makes two Claw attacks and uses Bite.

Claw. Melee Attack Roll: +7, reach 5 ft. Hit: 13 (3d6 + 3) Slashing damage  If the target is a Medium or smaller creature, it has the Grappled condition (escape DC 15) from one of two claws.

Bite. Constitution Saving Throw: DC 17, one creature within 5 feet that is willing or that has the Grappled, Incapacitated, or Restrained condition. Failure: 9 (2d6 + 3) Piercing damage plus 10 (3d6) Necrotic damage. The target’s Hit Point maximum decreases by an amount equal to the Necrotic damage taken, and Zevok regains Hit Points equal to that amount.

Arise! (Recharge 5–6). If there is not already a skeleton ally within 100 ft. of him, as a bonus action, Count Zevok points to a space containing a bat swarm and causes a skeleton to appear there. The skeleton immediately rolls into the initiative order. If holy water makes contact with Count Zevok, he cannot use this ability for 1 round.

Deathless Agility. Zevok takes the Dash or Disengage action