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AC 17 (natural armor)
HP 127 (15d10+45; bloodied 63)
Speed 45 ft.

Proficiency +3; Maneuver DC 15
Saving Throws Int ‒1
Skills Perception +5 (1d4), Stealth +6 (1d4), Survival +5 (1d4)
Damage Vulnerabilities radiant
Damage Resistances acid, fire, lightning, thunder; bludgeoning, piercing, and slashing from nonmagical weapons
Damage Immunities cold, necrotic, poison
Condition Immunities charmed , fatigue , frightened , grappled , paralyzed , petrified , poisoned , restrained
Senses darkvision 60 ft., passive Perception 18

Ethereal Sight. The cù-sìth can see 60 feet into the Ethereal Plane when it is on the Material Plane, and vice versa.

Incorporeal Movement. The cù-sìth 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.

Innate Spellcasting. The cù-sìth’s innate spellcasting ability is Charisma (spell save DC 14, +6 to hit with spell attacks). The cù-sìth can innately cast the following spells, requiring no material components:

At will: misty step

Keen Hearing and Smell. The cù-sìth has advantage on Wisdom (Perception) checks that rely on hearing or smell.

Magic Resistance. The cù-sìth has advantage on saving throws against spells and other magical effects.


Multiattack. The cù-sìth attacks twice.

Bite. Melee Weapon Attack: +7 to hit, reach 5 ft., one target. Hit: 10 (2d6+3) magical piercing damage. If the target is a creature, it must succeed on a DC 15 Strength saving throw or be knocked prone .

Howl of Terror (Recharge 6). The cù-sìth lets loose with a howl that chills the very soul of mortals. All living creatures within 2 miles of the cù-sìth that are able to hear it make a DC 14 Wisdom saving throw or are frightened for 1 minute.

A frightened creature that fails its save becomes panicked instead. A panicked creature must spend its turns trying to move as far away from the cù-sìth as it can. It also can’t take reactions. For its action, it can use only the Dash action or try to escape from an effect that prevents it from moving. If there’s nowhere to move, the creature can use the Dodge action.

A panicked creature that fails its save makes an additional DC 14 Wisdom saving throw or it dies instantly. As long as it is not able to see the cù-sìth, a frightened or panicked creature can use a bonus action on its turn to make a new saving throw, ending the effect on a success. Panicked creatures have disadvantage on this save.

Etherealness. The cù-sìth enters the Ethereal Plane from the Material Plane, or vice versa. It is visible on the Material Plane while it is in the Border Ethereal, and vice versa, yet it can’t affect or be affected by anything on the other plane.

Invisibility. The cù-sìth magically turns invisible until it attacks or until its concentration ends (as if concentrating on a spell).


Humanity so often today personifies death as the Grim Reaper, but there are many other, similar legends. This subject brings our species’ best friend into the mix to take on the job with the spectral dog known as the Cù-Sìth!

The Cù-Sìth is said to be as big a bull with paws the size of a human hand, shaggy dark green fur, and a long or otherwise strange tail. As mentioned above it’s a harbinger of death and shows itself to people who are about to enter the afterlife.

Roaming the highlands and wild moors of Scotland, the Cù-Sìth can stalk as well as any hunter but is known to let out three terrifying barks able to be heard from miles away. Hearing one of these barks strikes terror and those who perceive it flee for safety—for any who hear the third bark die from fright.

Monster Type Description

Fey are creatures that are native to Fairyland, also called the Dreaming. These creatures live in a verdant realm of heightened natural beauty and combine grace and danger. Sprites and pixies are fey.