The White Lady

Detect Life. The banshee magically senses the direction of creatures up to 1 mile away that aren’t Constructs or Undead.

Incorporeal Movement. The banshee can move through other creatures and objects as if they were Difficult Terrain. It takes 5 (1d10) Force damage if it ends its turn inside an object.

From the Icy Depths. While fully submerged in water, the banshee gains the Invisible condition.

Multiattack. The banshee makes two Freezing Touch attacks and uses Horrify. She can replace one of her Freezing Touch attacks with a Life Drain attack.

Freezing Touch. Melee Attack Roll: +5, reach 5 ft. Hit: 7 (1d8 + 3) Cold damage and the targets speed is reduced by 10 feet until the start of the banshees next turn.

Life Drain. Melee Attack Roll: +5, reach 5 ft. Hit: 7 (2d6) Necrotic damage. If the target is a creature, its Hit Point maximum decreases by an amount equal to the damage taken and heals the banshee up to half the damage dealt (rounded down).

Horrify. Wisdom Saving Throw: DC 13, one creature the banshee can see within 60 feet that can see the banshee. Failure: The target has the Frightened condition until the start of the banshee’s next turn. Success: The target is immune to this banshee’s Horrify for 24 hours.

Deathly Wail (1/Day). The banshee releases a mournful wail if it isn’t in sunlight. Constitution Saving Throw: DC 13, each creature within 30 feet that can hear the wail and isn’t a Construct or an Undead. Failure: If the target has 25 Hit Points or fewer, it drops to 0 Hit Points. Otherwise, the target takes 10 (3d6) Psychic damage.

The banshee has 2 Legendary Actions. She regains any expended uses at the start of her turn.

Drain Life. The banshee uses her life drain ability, restoring her Hit Points equal to the damage dealt.

Ethereal Movement. The banshee moves up to half her flying speed, without provoking opportunity attacks.