Battle aboard the Empirical Two years before the Battle of Yavin , a battle occurred on the " Empirical " in the Dominus system . The " Empirical " , a modified cruiser that belonged to the Sith Lord Darth Vader , was a mobile research vessel that conducted highly classified experiments on prisoners and unique alien species . In addition to a bridge crew of Imperial officers , the " Empirical ' s " security personnel was composed of a platoon of Imperial soldiers handpicked by Vader . Six months before the battle took place , Darth Vader discreetly transferred the damaged body of his unconscious apprentice , Starkiller , to the " Empirical " . Known only as " Subject 1138 , " the crew assumed that Starkiller was just another one of the Dark Lord ' s experiments . As a result of Vader ' s machinations , the entire crew was caught by surprise when Starkiller broke out of the medical bay in an escape attempt . As the ship ' s military personnel unsuccessfully attempted to kill the apprentice , the holodroid PROXY maneuvered the " Empirical " on a direct course for the Dominus system ' s star , in accordance with Vader ' s order to protect the secrecy of Starkiller ' s existence . Together with PROXY and former Captain Juno Eclipse , Starkiller escaped on the " Rogue Shadow " just before the " Empirical " was destroyed by the star . Prelude . After Starkiller assassinated Shaak Ti , a fugitive Jedi Master who had been hiding in exile on the planet Felucia , he was ordered to return to the " Executor " by the Sith Lord Darth Vader . By eliminating one of the last surviving members of the Jedi High Council , Starkiller ' s achievement was acknowledged by Vader , who assured his secret apprentice that the time had come to overthrow Darth Sidious , better known in public as the Emperor Palpatine . Though he contained his enthusiasm in front of his master , Starkiller was elated by the thought of finally becoming a true Sith . Aside from his service to Vader , the Emperor ' s downfall was a goal that Starkiller had been trained for over a number of years . Before returning to the " Executor " , Captain Juno Eclipse inquired about the future of her assignment as the eighth pilot of Starkiller ' s experimental stealth starship , the " Rogue Shadow " . Due to Starkiller ' s budding rapport with female officer , he promised to support her military career . He also envisioned his future as an official Sith Lord while Vader succeeded Sidious as emperor of the galaxy . Unknown to Starkiller , however , Eclipse inadvertently discovered Vader ' s scheme to assassinate the Emperor . Torn between her loyalty to her sovereign and commanding officer , she reluctantly remained silent on the issue . Upon his return to the " Executor " , Starkiller rendezvoused with Darth Vader on the bridge of the incomplete Super Star Destroyer . Beyond the viewport , both master and apprentice watched as the Emperor ' s fleet of Imperial Star Destroyers converged on the " Executor ' s " position . Starkiller assumed that Vader had manipulated Palpatine into a trap , but his assumption was proved incorrect when Vader stabbed Starkiller through the abdomen with his lightsaber ; the Emperor ' s spies , Vader claimed , had followed the apprentice all the way to the " Executor " . When Starkiller collapsed on the floor in utter shock and pain , Lord Sidious " entered " the chamber , communicating through the holodroid PROXY . After angrily accusing Vader of treason , specifically for training Starkiller in the first place , Sidious ordered him to kill the wounded apprentice . Faced with the threat of his own destruction , Vader complied and proceeded to telekinetically thrash his apprentice across the chamber . Afterward , he hurled Starkiller through the viewport and into the vacuum of space , much to Sidious ' sadistic delight . While Starkiller was unconscious , his body was collected from the vacuum by Darth Vader ' s droids and brought to the Dark Lord ' s science vessel , the " Empirical " . Other than his designation as " Subject 1138 , " the crew of the " Empirical " knew nothing else about Starkiller , and thus they simply regarded him as another one of Vader ' s secret experiments . For six months , Starkiller remained in a comatose state while his body was steadily repaired . During the process , Starkiller believed himself to be dead as he experienced a multitude of visions and memories . When he finally awoke , he was relieved for the end of the visions , but also became enraged when he saw Darth Vader . While Starkiller was restrained on the operating table , Vader revealed that the " execution " had been staged . According to Vader , Starkiller ' s life had been saved so that they could execute a new plan aimed at Sidious ' destruction . When Starkiller contemplated defiance , Vader threatened to kill him by activating the self - destruct sequence on the " Empirical " . However , Vader also pointed out that Starkiller had a second chance to fulfill his destiny by eventually becoming a true Sith Lord , as well as an opportunity for vengeance against Sidious . After considering his master ' s offer for a moment , Starkiller grudgingly agreed , and thus he was freed from his restraints . Escape from the Empirical . Darth Vader elaborated that with Palpatine ' s spies watching his every move , he needed a distraction to divert attention away from him . While the laboratory droids provided him with a new lightsaber , Starkiller suggested an assassination , though Vader dismissed it , as no single act of that kind would gain Palpatine ' s notice . Instead , Vader tasked Starkiller with a mission to create a rebellion that would challenge the Emperor ' s reign over the galaxy ; an alliance of rebels and dissidents . Vader gave Starkiller free rein in how to pursue his objective . However , Starkiller was also ordered to sever all ties to his past , with the exception of PROXY , in order to ensure that no one discovered his continued service to Vader . With a final assurance that the dark side of the Force was always with Starkiller , Vader ended his transmission , and thus revealed that he had been communicating through PROXY . PROXY was overjoyed by his master ' s survival , as it meant that he could still still have an opportunity to terminate Starkiller , which would then complete his primary programming . But due to Vader ' s orders , PROXY was focused on ensuring Starkiller ' s escape from their present location . Through PROXY , Starkiller learned that he was on board the " Empirical " in the Dominus system . PROXY then hacked into the ship ' s navigation system and placed it on a collision course with the Dominus star in accordance with Vader ' s wish that all witnesses were to be destroyed . In order to ensure that all Imperials aboard the " Empirical " died , PROXY also jettisoned all of the escape pods as well . When Starkiller inquired about Juno Eclipse , PROXY informed him that she was alive and onboard the " Empirical " . Her association with Starkiller effectively destroyed her career and she was declared a traitor to the Empire . As they encountered Imperial stormtroopers stationed aboard the doomed vessel , Starkiller activated his new lightsaber and realized that it was actually the former weapon of Jedi General Rahm Kota . Despite PROXY ' s cautious reminder that Starkiller was ordered by Vader to sever all connections to his past , the apprentice chose to make a beeline to the prison cell in order to retrieve Eclipse before the " Empirical " was destroyed . As Eclipse regained consciousness , she was surprised to see that Starkiller was still alive , despite the fact that she had been told of his " death " aboard the " Executor " . Although Starkiller disobeyed Vader by saving Eclipse ' s life , he chose to hide from her the fact that he still served the Dark Lord . After declaring his allegiance to the Empire at an end , the apprentice brought Eclipse with him , and explained his actions with the excuse of how he still required her as a pilot . Explosive bolts severed the umbilical that connected the " Rogue Shadow " to the " Empirical " just as they boarded , and Starkiller ordered PROXY to fly the ship away from the science vessel as it collided into the Dominus star . Eclipse took control of the ship almost immediately after , having regained most of her senses by then . Aftermath . Once they had escaped , Juno Eclipse confided in Starkiller her uncertainty about the future . Since her former life with the Empire was over , she was unsure of what to do with herself . Starkiller then revealed his plan to build an army in order to launch a full - scale rebellion against the Empire , though he purposely neglected to mention any detail about Darth Vader ' s involvement in the plot . With no other purpose left to follow , Eclipse agreed to aid his cause . Before Starkiller could begin his rebellion , however , he realized that he first needed to establish contact with the Empire ' s enemies . He then thought of Rahm Kota , the Jedi whom he suspected had survived their previous duel in the TIE Fighter Construction Facility above Nar Shaddaa . Their search for the general eventually led them to Cloud City on Bespin where Starkiller was forced to defend Kota — drunk and depressed — from Imperial soldiers . Behind the scenes . This conflict does not appear as a playable level in the Playstation 2 , PSP or Nintendo Wii versions of the game , although the event itself did happen those versions via cutscenes relating to Vader ' s rebuilding Starkiller and his new mission plans , and saving Juno Eclipse from the doomed ship . In the Xbox 360 / PS3 version , Starkiller is referred to as Subject 1138 .