Vahss, a hairless male Human, was affiliated with the Republic and a member of the Grace Command organization, which provided mercy during the New Sith Wars. In 1032 BBY, Vahss participated in a battle and met his death during an ambush orchestrated by the Hutt crime boss Zodoh's soldiers.
During the Republic Dark Age, Vahss was a member of the Republic Starfighter Corps alongside Captain Jenn Devaad. He was part of a Republic task force that was sent to Daalang, where they were captured and enslaved by the Hutt crime lord Zodoh after the local population declined to give them shelter. He and his companions were enslaved by Zodoh for five years until they broke free. This small group of survivors would become known as Devil Squadron and would pilot Fire Lotus-class starfighters for Baron Lemayne's Grace Command, a mercy organization focused on providing relief assistance to worlds occupied by the Sith. However, Grace Command was secretly a front for Lemayne's covert operations, including Operation Deluge, which involved flooding entire populations in Sith territory with the addictive spice Deluge in an attempt to weaken the Sith war effort. By 1032 BBY, Operation Deluge had successfully reduced the Sith's manpower, but it had also negatively impacted many civilian populations.
During the assault on Capital Cay, Vahss took part when Devil Squadron "liberated" Aquilaris from the forces of Daiman and Zodoh. He was later present at the spaceport as Jenn and the Jedi Knight Kerra Holt distributed food and medical supplies to the civilians. He questioned Jenn's choice to include Kerra Holt in their starfighter squadron, believing that the presence of a Jedi could complicate matters. Jenn dismissed his worries, assuring him that Kerra would be too focused on her own mission to notice anything suspicious about Grace Command. She also stated that Kerra would be a valuable asset in their fight against their adversary Zodoh, who was attempting to gain influence in the Grumani sector. Vahss also voiced his desire to get revenge on Zodoh for his past actions.
Jenn ultimately said that Kerra would never need to know about Operation Deluge if everything went according to plan. However, Joad Kreel, Kerra's childhood friend, overheard their private conversation and discovered Operation Deluge. The following day, Devil Squadron escorted the medical transport Mother Grace to a hyperspace jump-point in the Aquilaris Minor system. They then left on a mission to battle Lord Malakite's forces on Heptooine. On the way, they encountered Zodoh's Intruder-class starfighter, which led them into an ambush. During the ensuing dogfight, Devil Squadron found themselves trapped between Zodoh's flagship Voracious and a fleet of Stormdrivers, capital ships capable of creating artificial floods and storms.
After a dispute between Jenn and Kerra over the intercom, Jenn ordered Vahss to disable Kerra's Fire Lotus starfighter Devil Seven and bring her back in line. However, before he could carry out the order, his starfighter was shot down by one of Zodoh's Infiltrator starfighters. Vahss perished in the resulting explosion. His death saved him from the captivity, torture, and execution that befell his comrades at the hands of Zodoh, with the exception of Jenn.
John Jackson Miller had originally named Vahss "Voss" but changed it because the name was the same as one of his Facebook readers.