Unholy Agility. The Volatile Stalker can take the Dash or Disengage action as a bonus action.

Pack Tactics. The Volatile Stalker has advantage on attack rolls against a creature if at least one of the Stalker’s allies is within 5 feet of the creature and the ally isn’t incapacitated.

Horrifying Presence (Recharge 5–6). When a creature starts its turn within 30 feet of the Volatile Stalker and can see it, it must succeed on a DC 16 Wisdom saving throw or be frightened for 1 minute. A frightened creature can repeat the saving throw at the end of its turns, ending the effect on a success.

Daylight Burn. When exposed to sunlight, the Volatile Stalker takes 20 radiant damage at the start of each of its turns and has disadvantage on all attack rolls and ability checks.

Night Hunter. While in dim light or darkness, the Volatile Stalker has advantage on Dexterity saving throws, Stealth checks, and attack rolls.

Multiattack. The Volatile Stalker makes three attacks: one with its Bite and two with its Claws.

Bite. Melee Weapon Attack: +8 to hit, reach 5 ft., one target.
Hit: 19 (3d10 + 5) piercing damage, and the target must succeed on a DC 16 Constitution saving throw or take 10 (3d6) necrotic damage at the start of each of its turns until it is healed by magical means.

Claw. Melee Weapon Attack: +8 to hit, reach 5 ft., one target.
Hit: 14 (2d8 + 5) slashing damage.

Leap Strike (Recharge 5–6). The Volatile Stalker leaps up to 40 feet in a straight line and lands in a space adjacent to a creature. Each creature within 10 feet of where it lands must make a DC 16 Dexterity saving throw, taking 21 (6d6) bludgeoning damage and falling prone on a failed save, or taking half as much damage on a success.

Vengeful Frenzy. When the Volatile Stalker is reduced to 0 hit points, it can make one final Bite attack before collapsing.