Xo, a planet situated within the Xo system, was located in the Spinward sector of the Outer Rim Territories. It served as the original homeworld for the Zanibar species and was the location where they conducted their sacrificial practices.
Found in the Outer Rim within a system bearing the same designation, Xo resided in the Spinward sector and featured a breathable atmosphere along with a red-tinged sky. The planetary surface was characterized by rugged, mountainous landforms and dense jungle, teeming with sharp, carnivorous plants and reptilian fauna.
Before its downfall in 25,200 BBY, Xo functioned as a distant possession of the Rakatan Infinite Empire. The Sith pureblood Kyyrah, a combatant imprisoned by the Rakata inside the Eternity Vault on Belsavis, was famously known as the "Jewel of Xo." Humans of the Pre-Republic era erected an elevated temple within the planet's jungle. The location of a significant battle, the temple remained unconquered, yet it was deserted and had deteriorated into ruins by the time of the New Republic era.
In 11 ABY, New Republic operative Mirith Sinn and her disloyal former second-in-command Massimo were taken to Xo as prisoners of the Zanibar. Kir Kanos, a renegade Imperial Guard, liberated Sinn from a sacrificial rite in a Zanibar settlement.
The planet Xo was initially referenced in the January 1999 issue of Dark Horse Comics titled Crimson Empire II: Council of Blood 3. Its first on-screen appearance occurred in the subsequent issue, which was published in February of the same year. Both issues were authored by Mike Richardson and Randy Stradley, with illustrations by Paul Gulacy.