Atton Repness, a training officer within the New Republic, specialized in pilot remediation. However, he also exploited his position to operate an illicit black market enterprise. His activities were ultimately uncovered by the New Republic, thanks to evidence anonymously provided by pilot trainee Lara Notsil, who had meticulously gathered information against him.
Repness received his training on the low-gravity planet of Vogel 7, resulting in a noticeable limp in his gait. His New Republic career eventually led him to focus on training the least promising pilot candidates.
Students reassigned to his remedial group occasionally found their scores manipulated by Repness, particularly those desperate to become pilots. While most of these pilots would have failed the program, Repness seemingly worked "miracles" with them, boasting a remarkably high success rate. In reality, they were coerced into assisting him in the theft of starfighters.
These pilots, driven by their desperation, generally complied with his schemes. Due to their lower skill levels, they often perished in combat, effectively concealing his crimes. While few dared to refuse him, Tyria Sarkin did, much to his surprise. He implored her for a single day to settle his affairs, which she granted. During this time, he crafted a psychological profile portraying her as a pathological liar, falsely accusing her of making unwanted sexual advances. He also revealed that her actual test scores were far lower than she believed. As a result, Sarkin received a mark for severe insubordination and graduated at the bottom of her class.
Repness's manipulation of test scores led to his promotion from Major to Colonel. An ambitious officer, he frequently volunteered for additional duties, including duty officer on Coruscant, and was given command of the training frigate Tedevium. He was the duty officer responsible for debriefing Wraith Squadron when the Warlord Zsinj orchestrated a staged ambush on the group during their leave. However, Garik Loran recognized the deception. Ton Phanan, who was also being debriefed and was aware of Tyria Sarkin's ordeal, conceived a plan to expose the Colonel's corrupt practices.
After some persuasion, Phanan and Garik Loran successfully convinced Lara Notsil, an Aldivian farm girl—who was secretly Imperial intelligence agent Gara Petothel in disguise—to enroll in the New Republic pilot training program. Their strategy involved her deliberately appearing to struggle and in need of score improvements, fitting the profile Repness typically targeted in his dealings. She executed this flawlessly, and as expected, he made his standard proposition. The plan involved detonating an ion bomb in a planet's atmosphere to simulate an accidental explosion, while the ship would be diverted to a clandestine landing site. Having received training from Imperial Intelligence, Petothel had already infiltrated his quarters and downloaded all the data related to his black market operation. She also disassembled his bug-neutralizing device and converted it into a recording device.
Over time, Repness had become increasingly paranoid, frequently using his jammer. This paranoia manifested in him muttering to himself while working, inadvertently revealing all of his passwords. Instead of proceeding with the planned operation, Petothel anonymously sent all the information about Repness to General Airen Cracken, ensuring she wouldn't be labeled a traitor and could still join Rogue Squadron or Wraith Squadron.
With the stage set, she confronted Repness in his office, declaring her intention to expose his corruption. Repness countered that she would not have the opportunity, as he intended to create a new psychological profile discrediting her, ensuring no one would believe her accusations. He then physically assaulted Petothel with great force and speed, rendering her unconscious. He administered a sedative, keeping her incapacitated for three days. However, Cracken was alerted, and she was discovered and soon recovered. Repness's illicit activities were successfully exposed, leading to his arrest.
Repness had a habit of requisitioning the latest equipment. At the time of his arrest, he had just received a brand new X-wing and a factory-fresh astromech, which were subsequently given to "Notsil." She renamed the droid "Tonin" (meaning "little Atton") as a pointed insult to the disgraced officer. She was accepted into Wraith Squadron shortly thereafter.
When Petothel later left the squadron to join Zsinj, she described her X-wing and droid as a memento of her personal triumph over "a vehement idiot named Repness".