Fear Sensitivity. The daymare can sense anxiety and dread in creatures within 1 mile. After concentrating for 1 minute, the daymare can identify the nature and depth of the emotion, as well as any surface-level information related to the emotion (such as precipitating circumstance or object of affection). 

Invisibility. The daymare is invisible in the waking world.

Oneiric Mastery. Once rooted in a dream, the daymare has complete control over its surroundings and is able to manipulate the host psyche to produce any images it wishes.

Multiattack. The daymare makes two attacks.

Inception (waking world only). The daymare enters one sleeping creature's dream and begins manipulating its psychic energy. The target must make a DC 17 Charisma saving throw or take 27 (4d10 + 5) psychic damage and remain unconscious for 1 minute on a failure, or half damage and wake up on a success. Creatures that trance have advantage on the roll. Unconscious creatures may take regular combat turns while in the dream world, but they do not benefit from any movement while the daymare controls the dream. This state ends if the daymare is reduced to 0HP or it chooses to use this attack on another sleeping creature.

Mind Siphon (dream world only). Melee Weapon Attack: +9 to hit, range 5 ft.. Hit: 18 (4d6 + 5) psychic damage. If this attack reduces the target to 0HP, the target does not die, and instead takes one point of exhaustion and regains half of its hit points.

Absorb Psyche (dream world only). The daymare may regain hit points total to the Mind Siphon damage as an action. If the daymare absorbs 50% of its total HP from one target, it becomes visible in the waking world as its semi-corporeal form strengthens.

Manifest Nightmare (Recharge 5-6, waking world only).  Using psionic energy stolen from dreams, the daymare can cast Phantasmal Killer as an area of effect spell without components. Any creature within 60 feet must make a DC 17 Wisdom saving throw or be under the effects of that spell.