Cerebral Vampire

Shapechanger. The cerebral vampire can use its action to polymorph into a Tiny seagull, a Medium cloud of mist, or back into its true form. While in seagull form, the vampire can't speak, its walking speed is 5 feet, and it has a flying speed of 30 feet. Its statistics, other than its size and speed, are unchanged. Anything it is wearing transforms with it, but nothing it is carrying does. It reverts to its true form if it dies. While in mist form, the vampire can't take any actions, speak, or manipulate objects. It 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.

Misty Escape. When it drops to 0 hit points outside its resting place, the cerebral vampire transforms into a cloud of mist (as in the Shapechanger trait) instead of falling unconscious. If it can't transform, it is destroyed. While it has 0 hit points in mist form, it can't revert to its vampire form, and it must reach its resting place within 2 hours or be destroyed. Once in its resting place, it reverts to its vampire form. It is then paralyzed until it regains at least 1 hit point. After spending 8 hours in its resting place with 0 hit points, it regains 1 hit point.

Regeneration. The cerebral vampire regains 3 hit points at the start of its turn if it has at least 1 hit point remaining.

Vampire Weaknesses. The cerebral vampire has the following flaws:

Forbiddance. The vampire can't enter a residence without an invitation from one of the occupants. This does not extend to public places or places of business, as the invitation is implied.

Stake to the Heart. If a piercing weapon made of wood is driven into the vampire's heart while the vampire is incapacitated, the vampire is paralyzed until the stake is removed.

Vampire Repellants. A cerebral vampire cannot willingly move closer to pure alcohol if they can smell it, the face of a mirror if they can see it, or any holy symbols belonging to Lawful Good deities if they can see them.

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

Unarmed Strike (Vampire Form Only). Melee Weapon Attack: +9 to hit, reach 5 ft., one creature. Hit: (1d6 + 4) bludgeoning damage. Instead of dealing damage, the vampire can grapple the target (escape DC 18). On a hit, the target must succeed on a DC 16 Wisdom save, or come under the effects of confusion (such as that of the confusion spell).

Bite (Vampire Form Only). Melee Weapon Attack: +9 to hit, reach 5 ft., one willing creature, or a creature that is grappled by the cerebral vampire, incapacitated, or restrained. Hit: (1d6 + 4) piercing damage plus (1) Intelligence damage and (1) Wisdom damage. The reduction to these scores lasts until the target finishes a long rest. The target dies if this effect reduces either score to 0. A humanoid slain in this way and then buried in the ground rises the following night as a ghoul under the vampire's control.

Charm. The cerebral vampire targets one humanoid it can see within 30 ft. of it. If the target can see the vampire, the target must succeed on a DC 16 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 vampire or the vampire's 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 the vampire is destroyed, is on a different plane of existence than the target, or takes a bonus action to end the effect.

Children of the Night. The cerebral vampire magically calls 2d4 swarms of bats or rats. While outdoors, the vampire can call 3d6 wolves instead. The called creatures arrive in 1d12 rounds, acting as allies of the vampire and obeying its spoken commands. The beasts remain for 1 hour, until the vampire dies, or until the vampire dismisses them as a bonus action.