Magic Resistance. The Vampillithid has advantage on saving throws against spells and other magical effects.
Shapechanger. If the Vampillithid isn’t in sunlight or running water, it can use its action to polymorph into a Tiny bat or a Medium cloud of mist, or back into its true form.
While in bat form, the Vampillithid 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 Vampillithid 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, except the damage it takes from sunlight.
Misty Escape. When it drops to 0 hit points outside its resting place, the Vampillithid transforms into a cloud of mist (as in the Shapechanger trait) instead of falling unconscious, provided that it isn’t in sunlight or running water. If it can’t transform, it is destroyed.
While it has 0 hit points in mist form, it can’t revert to its Vampillithid form, and it must reach its resting place within 2 hours or be destroyed. Once in its resting place, it reverts to its Vampillithid form. It is then paralyzed until it regains at least 1 hit point. After spending 1 hour in its resting place with 0 hit points, it regains 1 hit point.
Regeneration. The Vampillithid regains 20 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 Vampillithid takes radiant damage or damage from holy water, this trait doesn’t function at the start of the Vampillithid’s next turn.
Innate Spellcasting (Psionics). The Vampillithid’s innate spellcasting ability is Intelligence (spell save DC 16). It can innately cast the following spells, requiring no components:
At will: detect thoughts, levitate
1/day each: dominate monster, blink
Spellcasting. The Vampillithid is a 12th-level spellcaster. Its spellcasting ability is Intelligence (spell save DC 16, +8 to hit with spell attacks). The Vampillithid has the following spells prepared:
Cantrips (at will): chill touch, dancing lights, mage hand, prestidigitation, shocking grasp
1st level (4 slots): detect magic, disguise self, arms of hadar, shield
2nd level (3 slots): suggestion, mirror image, tasha's mind whip
3rd level (3 slots): counterspell, thunder step, lightning bolt
4th level (3 slots): greater invisibility, Evard’s black tentacles, phantasmal killer
5th level (2 slots): synaptic static, scrying
6th level (1 slot): mental prison, mass suggestion
Vampire Weaknesses. The Vampillithid has the following flaws:
Forbiddance. The Vampillithid can’t enter a residence without an invitation from one of the occupants.
Harmed by Running Water. The Vampillithid 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 Vampillithid’s heart while the Vampillithid is incapacitated in its resting place, the Vampillithid is paralyzed until the stake is removed.
Sunlight Hypersensitivity. The Vampillithid takes 20 radiant damage when it starts its turn in sunlight. While in sunlight, it has disadvantage on attack rolls and ability checks.
Chilling Grasp. Melee Spell Attack: +8 to hit, reach 5 ft., one target. Hit: 10 (3d6) cold damage. Instead of dealing damage, the Vampillithid can grapple the target (escape DC 15).
Mind Blast (Recharge 5–6). The Vampillithid magically emits psychic energy in a 60-foot cone. Each creature in that area must succeed on a DC 16 Intelligence saving throw or take 22 (4d8 + 4) psychic damage and be stunned for 1 minute. A target can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.
Bite. (Bat or Vampillithid Form Only). Melee Weapon Attack: +5 to hit, reach 5 ft., one willing creature, or a creature that is grappled by the Vampillithid, incapacitated, or restrained. Hit: 4 (1d6 + 1) 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 the Vampillithid 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 Vampillithid's control.
Extract Brain. Melee Weapon Attack: +8 to hit, reach 5 ft., one incapacitated humanoid grappled by the Vampillithid that has suffered from the Bite attack. Hit: The target takes 55 (10d10) piercing damage. If this damage reduces the target to 0 hit points, the Vampillithid kills the target by extracting and devouring its brain.
The Vampillithid 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 Vampillithid regains spent legendary actions at the start of its turn.
Chilling Grasp: The Vampillithid makes a chilling grasp attack.
Emergency Shapechange: The Vampillithid uses its shapechange ability.
Blink (Takes 2 Actions): The Vampillithid activates its innate spell Blink if it has not already used it.