Apparition

Ethereal. Apparitions are a particularly horrible and persistant form of undead, existing primarly on the ethereal plane. While they can be seen in the material world they cannot be attacked, by non-ethereal weapons, unless its during a round they are using their Phantom Attack ability. Since they are non-corporeal, apparitions can travel directly to their intended destination without being hindered by physical barriers such as locked doors. Apparitions have an AC of 16 on the etheral plane.

Psychic Senses. Apparitions can telepathically sense any living creature of greater than 5 Intelligence, within 100 feet.

Surprise Attack. Apparitions have the ability to "pop in" from any solid, non-living object, such as walls, floors, or furniture. This will most likely surprise their opponent, giving them a 17 Stealth check against their opponent's passive Perception. Apparitions will attempt to attack any surprised opponents first.

Turn Immunity. The apparition is immune to effects that turn undead.

Phantom Attack. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: variable (see below) psychic damage. The apparition is not able to physically attack its victim. If an attack succeeds against the target the apparition will claw at its throat and the victim will feel bony claw like fingers strangling them, even through armor. The victim becomes Restrained. A creature can use its action to make a DC 17 Strength check to free itself. Every round the victim is Restrained they take 30 points of psychic damage, less the average of the victim's Intelligence and Wisdom scores (rounded down).

Frightful Aura. While using their Phantom Attack ability, apparitions emit a Fear aura. Any living creature within 30 ft. (not including the target of the Phantom Attack) that sees the attack must make a DC 15 Wisdom saving throw, or become Frightened until the apparition is destroyed. A creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success. If a creature's saving throw is successful, the creature is immune to the apparition's Frightful Aura for the next 24 hours.