Subject 1138

Subject 1138, also known as "Starkiller," was a clone of Galen Marek, a Force-sensitive Human male trained by the Sith Lord Darth Vader as his secret apprentice. After the death of Marek, the original Starkiller, Vader endeavored to create a more powerful and obedient version of his fallen disciple, using a cloning facility on the planet Kamino to carry out this agenda. However, the procedure was imperfect, resulting in a series of unstable clones that succumbed to madness. Though initially impressing Vader with his progress, Subject 1138 was affected by the emotional imprints that he inherited from his template and consequently developed a fixation on Captain Juno Eclipse, a former Imperial officer whom Marek fell in love with. Dismissed by his master as another setback in a long line of failures, the clone fled from Kamino and began traveling across the galaxy to find Eclipse.

The clone infiltrated Cato Neimoidia to rescue General Rahm Kota, hoping that Marek's Jedi mentor would lead him directly to Eclipse. Kota, believing the clone was in fact Marek, tried to convince him to rejoin the Alliance to Restore the Republic, but "Starkiller" was neither concerned with the Rebellion nor interested in assuming his progenitor's identity. However, his determination to be with Eclipse was used by Darth Vader as a way to lure the clone back to Kamino, having captured the Alliance officer in a battle near the Itani Nebula.

Returning to his homeworld, Starkiller fought his way into the facility where he was created, battling stormtroopers as well as other clones of Marek while the Alliance Fleet laid siege to Kamino. Ultimately, the renegade clone was able to save Eclipse and, in the process, defeated the Dark Lord of the Sith in a lightsaber duel. As a result of the clone's actions, the Alliance prevailed against the forces of the Galactic Empire, securing their first major victory in the Galactic Civil War and taking Vader himself as a prisoner of war.

Text and facts from the “Subject 1138” article on Wookieepedia, licensed under CC BY-SA 3.0. Modified for this site.