Name: The Sluagh
Medium Fey, Chaotic Evil
Armor Class: 14 (natural armor)
Hit Points: 112 (15d8 + 45)
Speed: 30 ft., fly 60 ft.

STR 15 (+2) | DEX 18 (+4) | CON 16 (+3) | INT 12 (+1) | WIS 14 (+2) | CHA 14 (+2)

Skills: Stealth +8, Perception +5
Senses: darkvision 60 ft., passive Perception 15
Languages: Common, Sylvan
Challenge Rating: 8 (3,900 XP)

        Incorporeal Movement. The Sluagh 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.
        Keen Sight and Hearing. The Sluagh has advantage on Wisdom (Perception) checks that rely on sight or hearing.
        Flyby. The Sluagh doesn't provoke opportunity attacks when it flies out of an enemy's reach.
        Infectious Scream (1/day). The Sluagh unleashes a terrifying scream in a 30-foot cone. Each creature in that area must make a DC 16 Wisdom saving throw or become frightened for 1 minute. 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 or the effect ends for it, the creature is immune to the Sluagh's Infectious Scream for the next 24 hours.
        Shadow Invisibility. The Sluagh can become invisible in shadows, as if under the effects of the invisibility spell, as a bonus action.

Actions
        Multiattack. The Sluagh makes two attacks: one with its claws and one with its spectral longsword.
        Claws. Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: 13 (2d8 + 4) slashing damage.
        Spectral Longsword. Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: 9 (1d8 + 4) force damage.
        Fading Scream (1/day). The Sluagh lets out a haunting scream as a bonus action, causing it to become incorporeal and move up to its flying speed without provoking opportunity attacks. The Sluagh can make a Spectral Longsword attack against any creature it passes through during this movement.

Description: The Sluagh is a Scottish folklore creature that is said to be a group of restless spirits. According to Scottish mythology, the Sluagh is a type of fairy that is associated with death and the afterlife. The Sluagh is believed to be made up of the spirits of the dead who were not able to pass on to the afterlife.

Physical Appearance
The Sluagh is said to be a dark, shadowy creature that can take on different forms. It is believed to be about the size of a human, but with wings like a bird. The Sluagh is often depicted as having long, sharp claws and glowing red eyes. Its appearance is said to be ominous and foreboding.

Abilities and Powers
The Sluagh is said to have the ability to fly and is often associated with the wind. It is believed that the Sluagh can control the winds and can summon them at will. The Sluagh is also said to have the power to enter people's dreams and influence them.

Origins and Legends
The origins of the Sluagh are unclear, but it is believed to have originated in Celtic mythology. It is said that the Sluagh is a type of fairy that was banished from the Otherworld and forced to live on Earth. According to legend, the Sluagh is the spirits of the dead who were not able to pass on to the afterlife and were trapped on Earth.

The Sluagh is often associated with death and is believed to be a harbinger of doom. It is said that the Sluagh can be heard flying overhead, and that its appearance is a sign that death is near. Some legends say that the Sluagh can even take the souls of the living and bring them to the afterlife.