An alien that calls itself the “ruler of the dark universe”. Alien Babarue is the most cruel and merciless alien in the galaxy and plans to take over the universe. Its weapons are the blade on its right arm, and the chain flail fired from the rocket anchor on its left.

Alien Babarue visited the Ultra planet (the Land of Light) and used its chain flail to break into the Ultra Tower and then transformed into an imitation Ultraman Astra. Alien Babarue used its disguise to steal the Ultra Key, a device that controls the trajectory of the Ultra planet. Alien Babarue set the Land of Light on a collision course with Earth and flew to Earth, pursued by Zoffy, Ultraman, Jack, and Ace. The alien used its Astra disguise to deceive Leo and planned to make it fight the pursuing Ultras so they would defeat each other.

However, Ultraman King arrived and destroyed the Ultra Key, revealing Alien Babarue’s identity. The alien ran and hid among the Earthlings in human size. Ultraman Leo found the real Astra who had been frozen by Alien Babarue, and together the Leo brothers repaired the Ultra Key, but Alien Babarue returned to giant form to take it back. Alien Babarue overpowers the pair by attacking with its blade and flail, but in the end it is defeated by Ultraman Leo’s “Leo Kick”.