The Trailian sithspawn represented a specialized offshoot of the Trailian species, brought into existence by the machinations of Emperor's Hand Cronal. Cronal, utilizing genetic manipulation and dark side experimentation, converted a significant portion of the previously docile Trailian population into formidable combatants. These warriors were granted potent Force abilities, including the deadly Force lightning. Despite their immense power, they demonstrated unwavering allegiance to Cronal, who dispatched them on various campaigns to assault adjacent planets to Trailia. Ultimately, this race met its end at the hands of a band of explorers from beyond their world.
In The Monster Maker, this group was characterized as "a twisted dark race of warriors." Although not explicitly identified as Sithspawn, their origins, involving "genetic engineering and Dark Side power," align with the established narrative of how Cronal/Blackhole manufactured other Sithspawn.