Fauna
High above Originis' floating sky-reefs, the Caelfin slips between coral-pinnacle and cloud as a meter-long arrow of iridescent teal. Its hollow-boned frame weighs less than a loaf of bread, the long primaries layering rose-gold across teal and shading to pearl beneath. A forked tail trims and fans for thermals, and broad chord-resonant flight feathers hum a faint 540 Hz tone on the downstroke that other Caelfins read as a name. Forward-set amber-ringed eyes track Pale Sister even in daylight, and pit-thin nostrils above the curved beak read pressure shifts a kilometer ahead of a storm. Legs are short and clawed for clinging to vertical sky-reef walls, where colonies excavate wind-sculpted caverns into floating limestone. Throat plumage flushes deeper rose when alarmed, and a male's courtship dive ignites the primaries into a pearl-light flare so bright it casts a shadow on the cloud below. They roost in spiraled communal galleries that whistle with the planet's high winds.
The aerial Cael Veyari weave Caelfin primaries into wing-cloaks called silentstroke, believing the borrowed feather-chord lets a flier slip past stormwinds unheard. A Cael child's coming-of-age requires hand-feeding a wild Caelfin from a sky-reef ledge; if the bird sings a name back, the child takes it as their own. Killing a nesting pair is a clan-exile offense, and the Pale Sister's eclipse nights see Cael elders set out lit lanterns to guide returning flocks home.
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