Innate Spellcasting. The beings innate spellcasting ability is Charisma. It can innately cast the following spells (spell save DC 18), requiring no material components:

At will: detect magic, jump, mage armor (self only), speak with dead

1/day each: Finger of Death, Eyebite, Maddening darkness, True Polymorph

Maddening Aura. At the start of each of the being's turns, each creature of its choice within 10 feet of it must succeed on a DC 15 Wisdom saving throw or take 11 (2d12) psychic damage and become blinded until the end of their next turn, provided the warlock isn't incapacitated.

Sweet Whispers. Adi Haw Nyea is accompanied by a crow named "Sweet Whsipers". While Sweet Whispers is within 10 feet of Adi they have advantage on all saving throws against spells and similar effects.

Mental Defense. While the being is wearing no armor, its AC includes its Intelligence modifier.

Sweet Dreams. Melee Weapon Attack: +10 to hit, reach 5 ft. or range 20/60 ft, 1 target. Hit: 7 (1d4 + 5) piercing damage plus 16 (3d10) psychic damage. The target must succeed on a DC 15 Intelligence saving throw or become incapacitated. While incapacitated this way the creature is deafened and blinded. The incapacited targed can repeat the saving throw at the start of each of its turns, ending the effect on itself on a success. 

Fall (Recharge 6). The being speaks a commandment and targets up to 8 creatures within 30 feet of itself. Each creature must make a DC 18 Intelligence saving throw, falling prone, becoming paralyzed and blinded on a failed save, or taking 13 (3d8) psychic damage on a success. If a paralyzed creature takes damage or a minute has passed, all effects end on that creature.