Ilyan Regus, a male Human, held the rank of Grand Moff within the reconstituted Sith Empire. He also spearheaded Operation Dark Ice, an initiative centered around harnessing Ilum's Adegan crystals to create stealth technology for the Empire. However, Jedi Master Jaric Kaedan intervened, deploying Duros shock troopers to disrupt Imperial activities. While Kaedan met his end, he had previously assigned Kaleesh mercenaries to safeguard the Empire's sole crystal mine. Regus sought the destruction of the Kaleesh forces, but Darth Malgus cautioned against it, pointing out that the "triumph" on Corellia had depleted nearly ten percent of Imperial troops. Malgus suggested winning the Kaleesh over by challenging their leader, a proposition Regus vehemently rejected.
Although the crystals were obtained, the fleet's safe landing was jeopardized by Republic anti-aircraft weaponry. Despite the destruction of these guns and Admiral Shai's defeat, Malgus ultimately betrayed the Empire to establish his own dominion. In response, Regus assembled an urgent war council to deliberate on how to address Malgus's treachery.
The character of Grand Moff Regus in the MMO videogame Star Wars: The Old Republic was brought to life by the voice acting of the renowned Julian Sands.