Rayboo were antler-bearing mammals that were native to the desolate, icy ice tundra environment of the planet Hoth. These creatures emitted piercing, mournful calls and were the prey of wampas, apex predators at the summit of Hoth's food web, though their main prey was the tauntauns.
Within the established Star Wars canon as it exists today, the vocalizations of rayboo were crafted specifically for the Star Wars Battlefront video game, which saw its release on November 17, 2015. These sounds were derived from recordings of elks. While the game itself did not explicitly name the creature, its designation was disclosed in a blog post by the sound designers at EA Digital Illusions CE before the game's launch on July 23, 2015. The concept of Rayboo first appeared in the now non-canon Star Wars Legends continuity, where they received a mention in The New Essential Guide to Alien Species, a reference book from 2006 authored by Ann Margaret Lewis and Helen Keier.