Amalith (Vampiric Succubus)

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

While in mist form, Amalith can't take any actions, speak, or manipulate objects. Amalith 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. Amalith has advantage on Strength, Dexterity, and Constitution saving throws, and is immune to all nonmagical damage, except the damage she takes from sunlight.

Shapechanger (Succubus). Amalith can use her action to polymorph into a Small or Medium humanoid, or back into her true form. Without wings, Amalith loses her flying speed. Other than her size and speed, Amalith's statistics are the same in each form. Any equipment she is wearing or carrying isn't transformed. Amalith's Misty Escape acts as per below when she dies in a shape-changed form.

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

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

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

Regeneration. Amalith regains 20 hit points at the start of her turn if she has at least 1 hit point and isn't in sunlight or running water. If  Amalith takes radiant damage or damage from holy water, this trait doesn't function at the start of her next turn.

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

Vampire Weaknesses. Amalith has the following flaws:

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

Sunlight Hypersensitivity. Amalith takes 20 radiant damage when she starts her turn in sunlight. While in sunlight, Amalith has disadvantage on attack rolls and ability checks.

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

Reluhantis. Melee Weapon Attack: +9 to hit, reach 10 ft., one creature. Hit: 9 (1d10 + 7) slashing damage. (Vorpal).

Unarmed Strike (Vampire Form Only). Melee Weapon Attack: +9 to hit, reach 5 ft., one creature. Hit: 8 (1d8 + 4) bludgeoning damage. Instead of dealing damage, Amalith can grapple the target (escape DC 18).

Bite. (Bat or Vampire Form Only). Melee Weapon Attack: +9 to hit, reach 5 ft., one willing creature, or a creature that is grappled by Amalith, incapacitated, or restrained. Hit: 7 (1d6 + 4) piercing damage plus 10 (3d6) necrotic damage. The target's hit point maximum is reduced by an amount equal to the necrotic damage taken, and Amalith regains hit points equal to that amount. The target dies if this effect reduces its hit point maximum to 0.

Charm. One humanoid Amalith can see within 30 feet of her must succeed on a DC 23 Wisdom saving throw or be magically charmed for 1 day. The charmed target obeys Amalith's verbal or telepathic commands. The charmed creature is a willing target for the vampire's bite attack, or draining kiss.

Each time Amalith or her 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 Amalith is destroyed, is on a different plane of existence than the target, or takes a bonus action to end the effect.

Draining Kiss. Amalith kisses a creature charmed by her or a willing creature. The target must make a DC 20 Constitution saving throw against this magic, taking 39 (6d10 + 6) psychic damage on a failed save, or half as much damage on a successful one. The target's hit point maximum is reduced by an amount equal to the damage taken. The target dies if this effect reduces its hit point maximum to 0.

Amalith 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. Amalith regains spent legendary actions at the start of its turn.

Move. Amalith moves up to her speed (walking or flying) without provoking opportunity attacks.

Unarmed Strike. Amalith makes one unarmed strike.

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

Charm.(Costs 3 Actions). Amalith attempts to charm one creature.