Cù-Sìth (KOO-shee)

There are places in the forest where breath holds still—not out of fear, but deference. Among moss-thick roots and old stones slick with age, a shape may appear without approach. The Cù-Sìth does not arrive by path or clearing. It emerges when the moment is ready for it, its outline pressed into the edge of perception like the pause between heartbeat and echo.   It lingers where the trees grow closest, where twilight filters in ribbons and the ground remembers footsteps not taken. One might sense it first as a shift in weight behind the air, or in the silence that follows a bird’s song too cleanly. It does not growl or stir. The Cù-Sìth simply stands, its presence creating space the way a boulder does in a stream—by being unmovable without seeming disruptive.   Wind changes around it. Leaves turn without falling. Those who have passed near its presence say that sound seems to fold inward, that even the crunch of their own steps is softened. It is not an animal in the way the mind expects. It is a reminder that motion does not equal awareness, and that something may see you long before you see it.   Often, it is spotted on the rise of a hill or the far end of a glade, still as carved wood. Never leashed, never leaping, the Cù-Sìth offers no threat, no welcome—only witness. The moment you look away, it will be gone, not fled, not concealed. Gone. The place it stood will look no different, and yet you’ll know with the certainty of breath withheld that something has changed.   For days afterward, one might walk more slowly. Trees seem more watchful. Paths feel less empty. What the Cù-Sìth brings is not message or omen, but a deeper recognition of place—the rooted truth that something shares the land with you, and always has.  

Behavior & Communication

Cù-Sìth exhibit a layered form of spatial presence. While physically mobile, they do not traverse open terrain with speed or display; rather, they appear along the periphery of travel, matching the pace of those nearby without intervention. Their movement is not linear, but radial—emerging from behind terrain features without observable path or sound.   They communicate through posture and gaze, with ear angles and tail curvature denoting varying states of attunement. When present in pairs, they mirror each other’s stance precisely, creating the visual impression of symmetry in asymmetric terrain. No known vocalization has been recorded; however, a low-frequency hum has been observed in localized aether fields during prolonged sightings.   They neither confront nor follow, instead maintaining constant spatial awareness. Cù-Sìth have been observed to remain at the exact same position relative to a walking traveler for several kilometers, always at a visual distance. This behavior suggests a form of relational resonance rather than physical tracking. Individuals encountering them often experience a notable drop in internal urgency.   When at rest, they adopt a seated position that seems intentionally composed, facing points of environmental convergence—such as ley crossings, water borders, or ancestral stonework. Their duration in such positions ranges from seconds to full dawn intervals and appears independent of surrounding activity.  

Ecological Niche

The Cù-Sìth inhabits the high-moor forests, deep thickets, and ridgeline woods of Tír na nÓg. It prefers biomes where arboreal density is paired with fluctuating mist cycles and where memory saturation in soil is high. Old forests with layered canopy and subterranean quartz deposits are especially favored.   Its presence is not disruptive but stabilizing. Moss coverage tends to increase where Cù-Sìth sightings are frequent, and resonance fields across stone surfaces display improved harmonic convergence. While it does not clear ground or carve trails, it contributes to the continuation of migratory corridors by anchoring waypoints through repetition.   Cù-Sìth locations are sometimes marked by the emergence of spiral lichens or lopsided root exposure, both of which suggest long-term energetic pacing. These markers often serve as orientation aids for druids, weather watchers, and memorykeepers tracking cycles of the Realm. The being’s patterns do not follow seasonal rhythms, but rather hinge upon tonal shifts in human presence—appearing most frequently near reflective individuals or in areas of softened collective attention.  

Common Myths & Legends

Scotland – Gaelic Highlands
In Highland lore, the Cù-Sìth is feared and revered as a great spectral hound said to collect souls. Its emerald coat and silent tread are central to myths of its approach. In Tír na nÓg, while the creature retains visual similarities, it bears no link to death or danger, embodying instead the stillness often mistaken for warning.   Ireland – Pre-Christian Folklore
Celtic legends include tales of fae hounds who walk unseen paths alongside human travelers. The Cù-Sìth reflects these stories through its mirroring behaviors and threshold-bound appearances. It is not a guide, but a witness—an echo of presence rather than protection.   Isle of Man – Manx Tradition
Legends of supernatural canines who guard burial mounds or forest glades mirror the Cù-Sìth’s stationary observation. While myths describe guardianship through intimidation, the Realm version offers neither warning nor welcome, only alignment with space and silence.