Cu Sith

The size of a yearling calf, with dark green fur, this supernatural Scottish dog hunts in complete silence, but lets out exactly three terrible barks when it attacks, heard for miles around. The rule is simple and deadly: if you can't find shelter before the third bark, you die of pure terror. They say it serves the fairies, capturing women to nurse the children of the otherworld.

A supernatural dog the size of a bullock, with dark-green fur (uncommon in dogs), broad paws, and a coiled or braided tail. It hunts in silence, but lets out three terrible barks heard for leagues; whoever fails to take shelter by the third bark dies of terror.

Within the folk and mythological corpus compiled by the Codex Monstrorum, the creature Cu Sith occupies a distinctive role in the symbolic imagination of its culture of origin. Its mythos articulates primal human anxieties, the mystery of untamed wilderness, and social norms preserved through the lens of bestiary literature.

It belongs to the Sìthe (the fairy folk) and serves as the Otherworld's hunting hound; in some traditions it carries off women to the fairy mounds to nurse the fairies' children. It binds the fear of the night, the moorland mist, and fairy abduction.

On hearing the first of the three barks, one had to race to the safety of home or shelter before the third; moorland travelers feared it in the mist. Keeping cattle and women safe from the fairy mounds was a concern tied to it.

First appearance and primary records: The 'fairy dog' (cù-sìth, Scottish Gaelic) of the folklore of the Scottish Highlands and Islands; gathered in Gaelic tradition and in compilations of Celtic folklore. It parallels the Irish cú sí.

Oral transmissions and preserved manuscripts indicate that legends surrounding Cu Sith underwent substantive evolution over successive centuries. From archaic oral traditions to classical and medieval written records, each period reframed the creature according to its own ethical and cosmological paradigms.

An immense dog, the size of a young ox, with dark-green coarse fur, paws the size of human hands, glowing eyes; it moves silently, leaving huge tracks, and barks only three times.

It embodies the danger of the fairy Otherworld and of abduction, and the terror of the misty moor at night; the three-bark motif ritualizes the race for survival. It binds mist, fairies, and the boundary between worlds.

A Celtic spectral hound paralleling the English barghest and Black Shuck, yet singular for its green color and fairy (not demonic) origin; with the cat-sìth it belongs to the supernatural animals of the Scottish Sìthe.

Present in Highland folklore, Celtic literature, and compilations of spectral hounds; it differs from the English black dogs by its green color and fairy origin, the Otherworld hound of the Gaelic world par excellence.