Ommin was a male Sith king who existed a long time before the war between the First Order and the [Resistance](/article/resistance]. This Sith individual is known to have used a mechanical spine device referred to as an Ommin harness.
The 2020 novelization of the film, Star Wars: The Rise of Skywalker: Expanded Edition, mentioned Ommin. The audiobook version of the novelization, however, uses different phrasing that suggests the Ommin harness received its name from this king, even though the king's name is not explicitly stated in the novelization.
Within the Star Wars Legends continuity, Ommin held the position of king on the planet of Onderon. His initial mention occurred in the second issue of the Star Wars: Tales of the Jedi comic miniseries. This issue was penned by Tom Veitch, with illustrations by Chris Gossett, and was released by Dark Horse Comics on November 16, 1993. His first appearance took place in the first issue of the comic series Star Wars: Tales of the Jedi – The Freedon Nadd Uprising, authored by Tom Veitch, featuring artwork by Tony Akins, and published by Dark Horse Comics on August 2, 1994.