The probe alerts the Imperial fleet to the Rebels' location. The Empire launches a large-scale attack using AT-AT walkers, forcing the Rebels to evacuate their base. Han and Leia escape with and Chewbacca on the "Millennium Falcon", but the ship's hyperdrive malfunctions. While they hide in an asteroid field, where Han and Leia become romantic amidst the tensions, Vader hires several bounty hunters to find the "Falcon". Meanwhile, Luke travels with in his X-wing fighter to Dagobah, where he crash-lands. He meets a diminutive creature who later reveals himself to be Yoda; the Jedi master reluctantly accepts Luke as his apprentice after conferring with Obi-Wan's spirit. Luke learns more about the Force from Yoda, who uses it to lift the sunken X-wing out of the swamp.