Maarek Sienar Santhe, going by the callsign "Omicron Leader", was a Human male member of the Sienar and Santhe families, becoming a TIE pilot in the Imperial Navy. The heir of the wealthy Sienar and Santhe families, which owned several corporations, he was born on Coruscant. However, unlike the other members of his family, Sienar had no passion for engineering or business. But he did enjoy piloting, and ended up joining the Galactic Empire. He became an ace pilot, and led Omicron Squadron, a squadron of TIE/ad starfighters and later TIE/D Defenders. During the Galactic Civil War, the squadron pilots became among the Empire's top aces, and scored many victories over the Alliance to Restore the Republic.