Regeneration. Vladimir regains 15 hit points at the start of its turn. If the revenant takes fire or radiant damage, this trait doesn’t function at the start of Vladimir's next turn. Vladimir's body is destroyed only if it starts its turn with 0 hit points and doesn’t regenerate.

Rejuvenation. When the Vladimir's body is destroyed, his soul lingers. After 24 hours, his soul inhabits and animates another humanoid corpse on the same plane of existence and regains all its hit points. While the soul is bodiless, a wish spell can be used to force the soul to go to the afterlife and not return.

Turn Immunity. Vladimir is immune to effects that turn undead.

Vengeful Tracker. Vladimir knows the distance to and direction of any creature against which it seeks revenge, even if the creature and the revenant are on different planes of existence. If the creature being tracked by Vladimir dies, Vladimir knows.

Multiattack. Vladimir makes two fist attacks, or two Greatsword attacks. 

Fist. Melee Weapon Attack: +9 to hit, reach 5 ft., one target. Hit: 13(2d6 +6); bludgeoning damage. If the target is a creature against which Vladimir has sworn vengeance, the target takes an extra 14 (4d6), bludgeoning damage. Instead of dealing damage, Vladimir can grapple the target (escape DC 15) provided the target is Large or smaller.

Vengeful Glare. Vladimir targets one creature he sees within 30 feet of him and against which he has sworn vengeance. The target must make a DC 16 Wisdom saving throw. On a failure, the target is paralyzed until Vladimir deals damage to it, or until the end of Vladimir's next turn. When the paralysis ends, the target is frightened of Vladimir for 1 minute. The frightened target can repeat the saving throw at the end of each of its turns, with disadvantage if it can see Vladimir, ending the frightened condition on itself on a success. 

The Moon Piercer (+2 Greatsword) Melee Weapon Attack: +9 to hit, Reach 5ft., one target. Hit: 20(4d6+6) slashing damage. If the attack is against Strahd, the weapon deals an additional 14(4d6) slashing damage