Baelnorn

Legendary Resistance (3/Day, or 4/Day in Lair). If the baelnorn fails a saving throw, it can choose to succeed instead.

Magic Resistance. The baelnorn has Advantage on saving throws against spells and other magical effects.

Spellcasting. The baelnorn casts one of the following spells, using Intelligence as the spellcasting ability (spell save DC 19):

At will: Detect Magic, Detect Thoughts, Dispel Magic, Invisibility, Lightning Bolt (level 4 version), Mage Hand, Prestidigitation

1/day each: Clone, Guards and Wards

2/day each: Dimension Door, Scrying

Counterspell. The baelnorn casts Counterspell in response to the spell's trigger, using the same spellcasting ability as Spellcasting.

Frightening Glance. The baelnorn casts Fear, using the same spellcasting ability as Spellcasting. The baelnorn can't take this action again until the start of its next turn.

Multiattack. The baelnorn makes three attacks, using Arcane Burst or Paralyzing Touch in any combination. It can replace two attacks with a use of Spellcasting to cast Lightning Bolt (level 4 version).

Arcane Burst. Melee or Ranged Attack Roll: +11, reach 5 ft. or range 120 ft. Hit:31 (4d12 + 5) Force damage.

Paralyzing Touch. Melee Attack Roll: +11, reach 5 ft. Hit:10 (2d4 + 5) Cold damage, and the target has the Paralyzed condition until the start of the baelnorn's next turn.

Overwhelming Radiance. Constitution Saving Throw: DC 19, each creature in a 20-foot Emanation originating from the baelnorn; Undead have Disadvantage on this save. Failure: 11 (2d10) Radiant damage. Success: Half damage.

Recuperative Teleport. The baelnorn teleports up to 60 feet to an unoccupied space it can see and regains 11 (2d10) Hit Points. The baelnorn can't take this action again until the start of its next turn.