Huge Giant Bird Birdon has emerged from the Mt. Okuma. Birdon set up a nest for its eggs but in the process traps several civilian captives in the pile. Angered by the attack as Xio tries to save the trapped people, Birdon rampages and Daichi as Ultraman X arrives on the scene but both soon succumb to the poison injected by the monster. At that time, Alien Fanton Guruman triggers a secret operation!?