Petro served as a TIE/LN starfighter pilot for the Imperial Crimson Squadron, finding himself based on Cilpar's Kiidan during the year 4 ABY.
Upon their initial encounter, Petro directed insults at Tycho Celchu of Rogue Squadron, calling him an Alderaanian coward (Celchu was at that time posing as an Imperial pilot). In response, Tycho attacked Petro, landing multiple blows to prove he wasn't a pacifist.
According to Aldrich Kugel, a fellow pilot, Petro was "a bit aggressive" and a "jerk", known for holding onto grudges with the tenacity of "Wookiee nurses her cubs".