Battle of To - phalion Base The Battle of To - phalion Base was an attack launched by Grand Admiral Zaarin against Grand Admiral Thrawn to steal the Vorknkx Project . Background . The project ' s aim was to create a device rendering a freighter invisible . The testbed was the Corellian Corvette " Vorknkx " . Former Imperial Grand Admiral Zaarin had known about the project when he was the head of developing new technologies for the Empire . Shortly after his betrayal , Zaarin and his co - conspirators decided to take the cloaking device being tested in the Vorknkx Project . His forces attacked the research station , forcing the staff to move the project to a more secure location . The new laboratory for the project was built in To - phalion Base , a hollowed out asteroid that was once mined by the Empire . The asteroid base was guarded by other asteroids with turrets hidden on them . The exact location of this base was a secret ; however , Zaarin managed to slip a few spies into the base . Once the spies revealed the base ' s weak points , Zaarin sent an attack force of sixteen Muurian transport s escorted by TIE Defenders , a fighter whose development was under the command of Zaarin when he was a loyal Imperial admiral . The battle . First assault . The still - loyal Imperial Grand Admiral Thrawn dispatched a squadron of TIE Avenger fighters to aid To - phalion base . Thrawn ' s finest pilot , Maarek Stele , lead the squadron . The TIE Avenger squadron , combined with To - phalion Base ' s asteroid turret defenses managed to ward off the Muurian Transports . Then , towards the end of the skirmish , To - phalion base ' s asteroid turret defenses were knocked off - line . A shuttle , " Lambda 3 " , made an unauthorized launch from To - phalion Base ' s hangar . The pilot was one of Zaarin ' s spies . Maarek Stele destroyed the shuttle , as ordered . Stele and the rest of the squadron reported to To - phalion Base ' s hangar . Second assault . Since the sabotage caused by Zaarin ' s spy had knocked the base ' s turrets offline , Grand Admiral Thrawn was going to arrive on board the Nebulon - B frigate " Maru Ki " , with reinforcements . Thrawn was hoping Zaarin himself would show up , so he could capture or kill the traitor . Before Thrawn arrived , Zaarin sent a second attack force , this one consisting of 4 " Assassin " - class corvettes from group Rok , a group of assault transports , and a squadron of Assault Gunboats . To - phalion Base ' s turret defenses were still down , so Stele ' s squadron was launched to defend the base . Eventually , Thrawn arrived on the " Maru Ki " , and Zaarin ' s forces were driven off . Unfortunately , the traitors had succeeded in destroying all the asteroid turrets surrounding To - phalion Base ' s main asteroid base . Zaarin ' s last assault . Zaarin launched a last ditch attack to either capture of destroy the Vorknkx Project . He arrived on board his flagship , the Star Destroyer " Glory " . The ship launched waves of TIE / LN starfighter s , interceptors , bombers , and TIE Defenders . Grand Admiral Thrawn called in his task force to trap Zaarin . But , before his task force arrived , Zaarin ' s ships managed to damage the frigate " Maru Ki " very badly . While it made the jump to hyperspace , Thrawn and the crew managed to flee the ship on shuttles . Next , the traitor ' s Star Destroyer fired at To - phalion Base , knocking out its shields . The base staff launched Corvette " Vorknkx " in an effort to save it , but the remainder of Zaarin ' s spies were on board , and they flew it right into the hangar of " Glory " , with the experimental cloaking device on board . Shortly after these events , Thrawn ' s task force arrived . It consisted of the Star Destroyer " Grey Wolf " , the Interdictor Cruiser " Corvus " , and the Strike Cruisers " Ebolo " and " Daring " . " Corvus " had been delayed , however , and without the cruiser ' s gravity well generators to disable the hyperdrive engine on the " Glory " , Zaarin and his forces escaped with the Corvette " Vorknkx " , and its cloaking device . Aftermath . Unbeknownst to the traitors , Thrawn had a tracking device planted on the " Vorknkx " , so the task force could follow Zaarin , and end his traitorous insurrection .