Star Wars: The Force Unleashed (2012)

During hunting down the survived Jedi, Darth Vader accidentally met the force-sensitive boy. The Dark Lord grew him up and trained him with the training-program-droid named Proxy. Once ready, the secret apprentice was given the codename "Starkiller", with the assignment to hunt the Jedi. When the Emperor knew the existing of Starkiller, this caused Vader to betray his apprentice- leading to the change of Starkiller's destination.