Tyrus, a male Human, held the rank of major within the Imperial Army of the reconstituted Sith Empire. He was in command of the Second Battalion of the Fifth Infantry. During the Cold War against the Galactic Republic, Tyrus was stationed on Balmorra, where he supervised his battalion's engagements against the Balmorran resistance. After Besh Company suffered heavy losses during a mission to infiltrate the Okara Droid Factory and introduce viruses into its mainframe, he found it necessary to enlist assistance from external sources.