Yuul was a Sullustan ensign assigned to the engineering staff onboard the Admiral Ackbar during the blockade of the Murgo Choke. Lieutenant Yuul became one of the only surviving members of the engineering staff when the Dark Nest launched its attack against the ships of the Galactic Alliance Fifth Fleet. Yuul reported to Admiral Bwua'tu that Captain Urbok and Lieutenant Commander Reo had been killed by Gorog assassins, while Lieutenant Aramb had been paralyzed by their venom. Yuul presumed the Admiral himself would oversee engineering, but instead Bwua'tu gave Yuul an instant promotion. Captain Yuul returned to the engineering station to find out the condition of the Ackbar.