Vampiric Elder Brain Adult Red Dracolich

Shapechanger. If the vampire 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 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, except the damage it takes from sunlight.

Legendary Resistance (3/Day). If the monster fails a saving throw, it can choose to succeed instead.

Magic Resistance. The monster has advantage on saving throws against spells and other magic effects. 

Siege monster. The monster deals double damage to objects and structures. 

Unusual Nature. The dragon doesn’t require air or sleep.

Misty Escape. When it drops to 0 hit points outside its resting place, the vampire 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 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 1 hour in its resting place with 0 hit points, it regains 1 hit point.

Regeneration. The vampire 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 vampire 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 vampire can’t enter a residence without an invitation from one of the occupants.

Harmed by Running Water. The vampire 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 vampire’s heart while the vampire is incapacitated in its resting place, the vampire is paralyzed until the stake is removed.

Sunlight Hypersensitivity. The vampire takes 20 radiant damage when it starts its turn in sunlight. While in sunlight, it has disadvantage on attack rolls and ability checks.

Multiattack. (Base Form Only). The monster can use its Frightful Presence. It then makes four attacks: one with its bite, two with its claws, and one with its tentacle.

Bite. (Bat or Vampire Form Only). Melee Weapon Attack: +15 to hit, (vampire form) reach 15 ft (bat form) reach 5 ft . Hit: 19 (2d10 + 8) piercing damage plus 10 (3d6) necrotic damage plus 11 (2d10) psychic damage plus 7 (2d6) fire damage.

The target’s hit point maximum is reduced by an amount equal to the necrotic damage taken, and the monster 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.

Claw. Melee Weapon Attack: +14 to hit, reach 5 ft., one target. Hit: 15 (2d6 + 8) slashing damage.

Tail. Melee Weapon Attack: +14 to hit, reach 15 ft., one target. Hit: 17 (2d8 + 8) bludgeoning damage.

Tentacle. Melee Weapon Attack: +15 to hit, reach 15 ft., one target. Hit: 12 (1d8 + 8) psychic damage. If the target is Huge or smaller, it is grappled (escape DC 18). The dragon can have up to four targets grappled at a time.

Frightful Presence. Each creature of the monster's choice that is within 120 feet of the monster and aware of it must succeed on a DC 19 Wisdom saving throw or become frightened for 1 minute. A creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success. If a creature's saving throw is successful or the effect ends for it, the creature is immune to the monster's Frightful Presence for the next 24 hours.

Charm. The vampire 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 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 (1/Day). The vampire magically calls 2d4 swarms of bats or rats, provided that the sun isn’t up. While outdoors, the vampire can call 3d6 wolves instead. The called creatures arrive in 1d4 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.

Tadpole Brine Breath (Recharge 5–6). The dragon exhales brine in a 120-foot line that is 15 feet wide. Each creature in that area must make a DC 22 Constitution saving throw, taking 55 (10d10) psychic damage on a failed save, or half as much damage on a successful one. On a success or failure, if the creature isn’t a Construct or an Undead, it becomes infested with illithid tadpoles.

While infested, the creature takes 16 (3d10) psychic damage at the start of each of its turns. The creature can repeat the saving throw at the end of each of its turns, ending the effect on itself after it succeeds on three of these saves. If the creature is targeted by magic that ends a curse or restores 40 hit points or more, the tadpoles infesting the creature are killed instantly, ending the effect on the creature.

If a Humanoid is reduced to 0 hit points while infested, the creature is stable but remains unconscious for (6d12) hours. When the period of unconsciousness ends, the creature transforms into a vampiric mind flayer (see the Monster Manual) with all its hit points. Casting a wish spell on the unconscious creature rids it of the infestation and prevents it from turning into a vampiric mind flayer.

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

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

Detect. The dragon makes a Wisdom (Perception) check.

Claw Attack. The dragon makes one claw attack. 

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

Tentacle. The dragon makes one Tentacle attack.

Shatter Concentration (Costs 2 Actions). The dragon targets a creature it is grappling. The target’s concentration on a spell it has cast or an ability it is maintaining ends, and the target takes 19 (3d12) psychic damage.

Wing Attack (Costs 2 Actions). The dragon beats its wings. Each creature within 10 feet of the dragon must succeed on a DC 22 Dexterity saving throw or take 15 (2d6 + 8) bludgeoning damage and be knocked prone. The dragon can then fly up to half its flying speed.