Clovus Espera [ADJUST ACCORDINGLY BASED ON WHEN PLAYERS ENCOUNTER]

Shapechanger. If Clovus isn't in sunlight or running water, he can use his action to polymorph into a Tiny bat or a Medium cloud of mist, or back into his true form.

While in bat form, Clovus can't speak, his walking speed is 5 feet, and he has a flying speed of 30 feet. His statistics, other than its size and speed, are unchanged. Anything he is wearing transforms with him, but nothing he is carrying does. He reverts to his true form if he dies.

While in mist form, Clovus can't take any actions, speak, or manipulate objects. He is weightless, has a flying speed of 20 feet, can hover, and can enter a hostile creature's space and stop there. In addition, if air can pass through a space, the mist can do so without squeezing, and it can’t pass through water. He has advantage on Strength, Dexterity, and Constitution saving throws, and it is immune to all nonmagical damage, except the damage it takes from sunlight.

Legendary Resistance (2/Day). If Clovus fails a saving throw, it can choose to succeed instead.

Misty Escape. When he drops to 0 hit points outside his resting place,  Clovus transforms into a cloud of mist (as in the Shapechanger trait) instead of falling unconscious, provided that he isn't in sunlight or running water. If he can't transform, he is destroyed.

While he has 0 hit points in mist form, he can't revert to his vampire form, and he must reach its resting place within 2 hours or be destroyed. Once in his resting place, he reverts to his vampire form. He is then paralyzed until he regains at least 1 hit point. After spending 1 hour in its resting place with 0 hit points, he regains 1 hit point.

Regeneration. Clovus regains 25 hit points at the start of his turn if he has at least 1 hit point and isn't in sunlight or running water. If he takes radiant damage or damage from holy water, this trait doesn't function at the start of Clovus' next turn.

Supersonic Speed. Whenever Clovus moves 50 ft. or more in a single movement, creatures and objects within 5 ft. of his origin point take 5 (1d10) thunder damage. Additionally, attacks of opportunity against Clovus have disadvantage.

Supernal Physiology. Clovus has advantage on Strength checks and saving throws, as well as Dexterity saving throws.

Spider Climb. Clovus can climb difficult surfaces, including upside down on ceilings, without needing to make an ability check.

Vampire Weaknesses. Clovus has the following flaws:

Forbiddance. Clovus can't enter a residence without an invitation from one of the occupants.

Harmed by Running Water. Clovus takes 20 acid damage if it ends its turn in running water.

Stake to the Heart. If a piercing weapon made of wood is driven into the Clovus' heart while the he is incapacitated in his resting place, Clovus is paralyzed until the stake is removed.

Sunlight Hypersensitivity. Clovus takes 20 radiant damage when he starts his turn in sunlight. While in sunlight, he has disadvantage on attack rolls and ability checks.

All-Consuming Rot. Clovus has been cursed by Moander for his hubris, but due to his undead nature can not truly die from his condition.
Starting on his second combat turn, at the beginning of each of his turns, Clovus must make a Constitution saving throw. If he fails this saving throw, his Strength score is reduced by 2 to a minimum of 12 and his speed is reduced by 20 ft. to a minimum of 50 ft. until he spends at least 8 hours in his resting place. The DC for this saving throw is 6, and it increases by 2 every time he succeeds.

Multiattack. (Vampire Form Only). Clovus makes three attacks, only one of which can be a bite attack.

Unarmed Strike (Vampire Form Only). Melee Weapon Attack: +11 to hit, reach 5 ft., one creature. Hit: 11 (1d10 + 6) bludgeoning damage. Instead of dealing damage, Clovus can grapple the target (escape DC 19).

Bite. (Bat or Vampire Form Only). Melee Weapon Attack: +11 to hit, reach 5 ft., one willing creature, or a creature that is grappled by the vampire, incapacitated, or restrained. Hit: 9 (1d6 + 6) piercing damage plus 14 (4d6) necrotic damage. The target's hit point maximum is reduced by an amount equal to the necrotic damage taken, and the vampire regains hit points equal to that amount. The reduction lasts until the target finishes a long rest. The target dies if this effect reduces its hit point maximum to 0. A humanoid slain in this way and then buried in the ground rises the following night as a vampire spawn under the vampire's control.

Charm. The Clovus targets one humanoid it can see within 30 feet of it. If the target can see the vampire, the target must succeed on a DC 17 Wisdom saving throw against this magic or be charmed by him. The charmed target regards Clovus as a trusted friend to be heeded and protected. Although the target isn't under Clovus' control, it takes his requests or actions in the most favorable way it can, and it is a willing target for the his bite attack.

Each time Clovus or his companions do anything harmful to the target, it can repeat the saving throw, ending the effect on itself on a success. Otherwise, the effect lasts 24 hours or until Clovus is destroyed, is on a different plane of existence than the target, or takes a bonus action to end the effect.

Clovus can take 3 legendary actions, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature's turn. Clovus regains spent legendary actions at the start of his turn.

Umbral Dash. Clovus moves up to half his speed and can make an Unarmed Strike immediately after. This movement always benefits from Supersonic Speed.

Maddened Wail. Clovus lets out a horrifying wail of sorrow and pain targeting a creature within 60 feet of him. The target must succeed on a DC 17 Wisdom saving throw or become frightened of Clovus for 1 minute. Frightened targets can repeat this saving throw at the end of their turns.
A creature that successfully saves against this feature is immune to it for 24 hours.

Bite.(Costs 2 Actions). Clovus makes one bite attack.