Holy crap, you guys are all mixed up. If you don't believe the following statement, verify it on Wookiepedia, the Star Wars Wiki. Starkiller died at the end of the first game. The game and book confirm this. But Vader was lying the entire time about never planning to kill the Emperor. He tried to kill Starkiller so the Emperor would not sense his deception.
After Starkiller's death Vader took his body to Kamino and made a clone. The clone experiences the old Starkiller's memories, and Vader's taunting made him doubt his mental stability. So the clone seeks out his old self's friends, Leia, Kota, Juno, and everyone else. Am I the only one who reads Wookiepedia?You PLAY AS HIS CLONE! STARKILLER DIDN'T SURVIVE!