Baron von Getrank

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

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

While in mist form, the baron 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. It 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 (5/Day). If the vampire fails a saving throw, it can choose to succeed instead.

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

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

Vampire Weaknesses. The vampire has the following flaws:

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

Harmed by Running Water. The baron 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 baron's heart while he is incapacitated in his resting place then he is paralyzed until the stake is removed.

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

Spellcasting. The baron is a 9th-level spellcaster. His spellcasting ability is Intelligence (spell save DC 16, +8 to hit with spell attacks). The baron has the following wizard spells prepared:

Cantrips (at will): mage hand, prestidigitation, ray of frost

1st level (6 slots): comprehend languages, fog cloud, sleep, charm person

2nd level (5 slots): detect thoughts, gust of wind, mirror image

3rd level (5 slots): animate dead, bestow curse, nondetection

4th level (4 slots): blight, greater invisibility

5th level (2 slots): dominate person

Multiattack. (Vampire Form Only). The baron casts one spell or charm and makes two attacks, only one of which can be a bite attack.

Hook Cane 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, the baron can grapple the target with the hook of his cane (escape DC 18).

Bite. (Bat or Vampire Form Only). Melee Weapon Attack: +10 to hit, reach 5 ft., one willing creature, or a creature that is grappled by the baron, incapacitated, or restrained. Hit: 20 (3d6 + 7) piercing damage plus 20 (3d12) 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 the baron's spawn under the his control.

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

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

The baron can only have one target charmed at a time.

The baron 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. The baron regains spent legendary actions at the start of its turn.

Move. The baron moves up to its speed without provoking opportunity attacks.

Unarmed Strike. The baron makes one unarmed strike.

Bite.(Costs 2 Actions). The baron makes one bite attack.

Call Mosquitoes. (Costs 2 Actions). The baron calls forth a swarm of mosquitoes that bite anybody in a ten foot radius at the baron's choosing. The mosquitoes cause 3d6 damage with half the damage dealt adding to the baron's health. Anybody bitten by them must make a DC 10 Constitution saving throw, on a fail they will be itchy on their next turn and roll attacks at a disadvantage.