Aura of Eyes. The ghost shaman adds its charisma bonus to its AC.

Multiattack. The ghost shaman attacks twice with its death's touch or makes one death's touch attack and uses Evil Eye once.

Death's Touch. Melee Weapon Attack: +9 to hit, reach 10 ft., one target. Hit: 21 (6d6) necrotic damage, and target must make DC 15 Charisma save or be slowed.

Evil Eye. The fomorian magically forces a creature it can see within 60 feet of it to make a DC 15 Charisma saving throw. The creature takes 27 (6d8) psychic damage on a failed save, or half as much damage on a successful one.

Spirits of Possession. The fomorian ghost shaman targets one creature that has taken necrotic damage from it during the combat. The target must make a DC 15 Wisdom saving throw.  On a failed save, the target is charmed. The charmed target must use its reaction, if available, to move up to their speed and then make either a melee attack or fall prone as directed by the ghost shaman. The effect ends once the target uses their reaction or the ghost shaman finishes its turn.

Darksoul Mist (Recharges 4-6).   Each creature in a 20-foot-diameter cube centered on a point within 60 feet must make a DC 15 Charisma saving throw or be slowed. A target takes 21 (6d6) necrotic damage and is slowed on a failed save, or half as much damage on a successful one. The cube of darkness remains for one minute, obscuring vision.

Curse of the Evil Eye (Recharges after a Short or Long Rest). With a stare, the fomorian uses Evil Eye, but on a failed save, the creature is also cursed with magical deformities. While deformed, the creature has its speed halved and has disadvantage on ability checks, saving throws, and attacks based on Strength or Dexterity.

The transformed creature can repeat the saving throw whenever it finishes a long rest, ending the effect on a success.