In Hyperborea’s northernmost mountains, there exists a sanctuary where comets come to roost. Here, natural philosophers have been able to observe some of their more avian characteristics up close: their bodies are covered from nucleus to tail in transparent feathers, and their parrot-like faces can be vaguely discerned underneath the icy mists that surrounds them. Their wings are extraordinary in span, yet are never unfurled during their travels through space, as there is no atmosphere against which to propel themselves.

Despite their beauty, long-term exposure to these tranquil creatures is not recommended, for their presence is an omen of dark times ahead for all humans who observe them. Many researchers, captivated by their natural brilliance, end up damning themselves to an early demise.

While the presence of live comets on Earth is extraordinary in its own right, the resultant effects on the surrounding biome are perhaps more intriguing. These northward migrations have been taking place for tens of millions of years, resulting in integral relationships with other forms of life. Flowers like the black-petaled snowroot can only grow when watered with their molten ice, and whispers of raven moths congregate around their glowing corpses as part of their mating rituals.

There is no species in which the wild comet’s influence is more pronounced, however, than it is within the Riphean condor. Named for the mountains in which it dwells along the region’s southern border, it is the result of improbable crossbreeding between ancient Hyperborean vultures and comets. While similar in appearance to its Californian cousin, the Riphean variety features transparent tail feathers, as well as a spherical coma of dust obscuring its grotesque complexion. The most important trait inherited from its celestial ancestors is invisible, however: its existence as a harbinger of death.

Flocks of these vultures search for high places and open clearings in which to gather, making it difficult for travelers to ignore their luminous heads. Once they know that they’ve been seen, they then stalk their prey for as many miles as it takes, for their scavenger’s feast has been guaranteed. Because of this, climbers who seek to conquer Riphean peaks are considered fools by the local population, and advised to do so blindfolded.

It is said that there is a priestess whose power over the past can undo the Riphean condor's curse.

Despite extreme physiological differences, wild libraries doom their prey in a similar manner.