Carved from a single shard of meta-crystalline obsidian, the Stygian Sundial's faceted surfaces refract all light into frozen fractals of shadow. Within its inky depths, faint etchings of cosmic coordinate systems hint at unfathomable celestial calculations. An aura of intense cold emanates from the artifact, sculpting delicate hoarfrost across any surface it touches.

The Stygian Sundial does not actively intervene, but its mere presence alters the realms it inhabits, transforming warmth into eternal winter and casting an eerie pall wherever its obsidian shadow stretches.