The Trailians were a sentient, humanoid species of remarkable beauty. Originating from the Outer Rim planet of Trailia, they had established a society with limited technological advancement by the time the New Republic emerged. During this era, Cronal, a prominent Emperor's Hand, set up a laboratory on their world and conducted experiments on the Trailians, transforming these formerly peaceful people into savage warriors. These altered beings were unleashed upon neighboring planets until a group of travelers from other worlds defeated them.
The Trailians were a sentient species of humanoids. Each member possessed Force-sensitivity with significant untapped potential, and they were renowned for their striking physical attractiveness.
The Trailians existed within a society marked by limited technological progress. They formed communities in villages, coexisting peacefully with their planet's natural surroundings. The limited technology they possessed was based on natural adaptations. In terms of culture, the Trailians were generally peaceful; however, after being subjected to experimentation, they transformed into formidable warriors with exceptional combat and Force abilities.
The Trailians evolved on Trailia, a planet teeming with tropical life situated in the far-flung Dominus sector of the Outer Rim Territories, close to the Dark Nebula. By the time of the New Republic, they had cultivated a tranquil society with minimal technological advancement. However, this peaceful existence was disrupted when Cronal, one of the Galactic Emperor Palpatine's most potent servants of the dark side and an Emperor's Hand, discovered the planet sometime after his banishment. He secretly established a hidden laboratory deep within the planet's jungles and initiated the capture of native Trailians.
By combining genetic manipulation with dark side experimentation, Cronal transformed his prisoners into a brutal breed of Trailian sithspawn, with the intention of using them to dismantle the New Republic. While some of these warriors remained to guard his fortress, where an army of them was being bred alongside similarly altered animals, Cronal deployed warriors on missions to other planets to assess their combat effectiveness. News of those warriors' unprovoked attacks on unsuspecting planets quickly spread, and the remaining peaceful Trailians grew anxious about the increasing disappearance of their people. They offered a reward for anyone willing to investigate, which drew a group of offworlders to Trailia.
Among the offworlders was a Force-sensitive individual who detected the dark side energy emanating from Cronal's fortress, guiding the group to its location. During a decisive battle, they overcame the mutated Trailian guards and other creatures, ultimately breaching the fortress. However, Cronal managed to escape the battle. Similarly, some of his warriors secured transportation offworld and continued to devastate cities until the same group of offworlders tracked them down and defeated them.
As for Cronal, he escaped to the underlevels of the planet Coruscant, accompanied by several of his elite Trailian technobeasts. These Trailians were subsequently killed when Cronal attempted to transform the Human Irek Ismaren into a massive cyborg warrior, resulting in the newly-modified Ismaren embarking on a violent rampage.
The Trailians were conceived by Bill Olmesdahl for the Star Wars Gamemaster Screen, a product by West End Games designed for the second edition of their role-playing game. Published in 1992, the book provides adventure seeds for game masters to expand upon. The Trailian adventure is entitled "The Monster Maker." In addition to the primary storyline, Olmesdahl suggests an extension where mutated Trailians escape offworld, leading to encounters with player characters on other planets. This has been integrated into the storyline above as an extension to the main campaign.
The precise date of Cronal's experiments on the planet is not specified; however, it occurs during the New Republic's reign, therefore after its establishment in 5 ABY. In subsequent sources, Cronal has been identified as both Blackhole and Lord Shadowspawn. Given that he remains alive until at least 9 ABY, this adventure could take place at any point during the New Republic era.