Olfmeri

The olfmeri, colloquially known as the sky leviathan or the space whale, is an elusive and mysterious creature described as an "avian cetacean", placed on several Forerunner installations by the Lifeworkers.

History
Olfmeri were among the creatures preserved by the Librarian against the firing of the Halo Array in 97,445 BCE. Following this destructive event they were seeded upon at least one Halo ring while also being left to flourish on the Ark, Installation 00, far beyond the Milky Way galaxy.

In December of 2552 the  captured audio recordings of olfmeri songs after arriving at the Ark. Soon after this an unfinished Halo ring was fired above the Ark, spelling death for the many sentient creatures which inhabited its surface. The Ark's monitor, 000 Tragic Solitude, eventually then began to breed new life forms. Among these were more olfmeri. A joint UNSC–Swords of Sanghelios task force, including Doctor Luther Mann, later encountered a pod of olfmeri during a covert mission to Installation 00 in March of 2555. Using his knowledge of the olfmeri's calls, Mann was able to briefly call to one.

Biology
The creatures are large with somewhat-bulbous, teardrop shapes. They have large, toothy mouths that extended across their fronts and about a third of the way down their sides. The creatures' undersides are pure white.

The olfmeri's ability to defy gravity seems almost impossible, given the incredible size and nature of these beasts. A passive species, these leviathans are as large as many species of whale found on Earth and bear striking similarities to the huge aquatic mammals, but with one key difference: while whales on Earth inhabit the planet's oceans, olfmeri are capable of flying through the skies. The biological mechanisms behind their buoyancy is still a mystery to scientists of the Office of Naval Intelligence, though there are no shortage of curious theories.

Behavior
"The songs don't serve as a language in the same way that words do for us. It conveys feelings, sensations."

- Doctor Luther Mann

Olfmeri traveled together in pods. The creatures are apparently passive, and show interest in investigating new species. The creatures communicate with each other by "singing" and whistling; these vocalizations are slightly painful to human ears. The olfmeri communicate not as a form of language, but to convey feelings and sensations. Humans have the ability to mimic these vocalizations. During Operation: FAR STORM, Doctor Luther Mann mimicked the calls of a olfmeri and attracted one of the creatures. However, the olfmeri quickly flew off upon realizing that Mann was not a member of its species.

Production notes
The sky leviathan was planned to be featured in Halo 4. It was an enormous flying whale-like creature that would have lived on Requiem. The concept art was drawn by 343 Industries artist Paul Richards. This design was later canonised in the Halo: Outpost Discovery Ring Experience.

List of appearances

 * Halo: Hunters in the Dark
 * Halo: Outpost Discovery