Darth Starkiller, formerly Galen Marek, was a Human male Sith Lord who served under the Galactic Empire and Emperor Palpatine. He chose to strike down his former master, Darth Vader during his rescue of the future leaders of the Alliance to Restore the Republic. After a failed attempt to betray Palpatine as well, the Emperor brought the Rogue Shadow down onto him, crushing his body, resulting in his body reconstructed similar to Vader's. Stripped of a powerful apprentice, Starkiller was forced to serve as Palpatine's personal assassin until he could find a suitable replacement.