The "phantom passenger" was a mysterious, decorporalized entity that was capable of taking over droids and other technological devices. The entity, which was encountered by Graysom, Kanan Jarrus and Hera Syndulla near an asteroid belt, claimed to have once been a powerful Force-user whom the Jedi stripped of his physical form and trapped among the stars many centuries before the early rebellion against the Galactic Empire. Although it managed to take over the droid brain of Syndulla's starship, the Ghost, and then the body of the astromech droid Chopper, the "phantom passenger" was finally tricked into entering an empty, powerless holocron, in which it was trapped.