Pokemon The Movie 08: Lucario and the Mystery of Mew

Sir Aaron, the True Guardian of Aura, saved Camaron Palace from destruction by sacrificing himself to stop a war between kingdoms. To commemorate his deed, an annual tournament is held, and Satoshi, a young Pokémon trainer from Kanto, wins the latest one. He's granted Sir Aaron's staff, from which Lucario, the Aura Pokémon, emerges. However, Lucario runs away, recalling his master's abandonment.