Sasahiler try to render mankind lazier but was forced to actively fighting Jack after his plan failed, resulting from a death by Specium Ray. He is voiced by Isao Yatsu. : A race of aliens that constantly at war with Alien Atelier. The first Mysteler is a combat captain who wishes to enlist MAT and Ultraman Jack as part of Mysteler's military troop. After attempts to get a fugitive soldier to his side fails, he threatens Ultraman Jack with the brainwashed MAT members. He tried to escape with his space saucer, but MAT members intercepted him in time and ended his evil plot on Earth. He is voiced by , who also portrays his unnamed human form. Hoshino: An old man who is actually a Mysteler veteran that wanted to flee from his home world's conflict. He was forced to kidnap Jiro and Rumiko when his old captain threatened with killing Emi. Seeing the error of his ways, Hoshino try to fight him but Jack saved the alien in time and therefore allowing both father and daughter to live in peace. He is portrayed by . Emi Hoshino: The human form of the heroic Mysteler's daughter, she was originally kidnapped by the brainwashed Oka and Ueno before Go disabled them. Emi managed to stop her father from killing Go when the Mysteler captain threaten him and finally continued living her life as a human. She is portrayed by . : A race of aliens that went on a war with residents of Planet Mysteler. This conflict is still ongoing even during the era of Ultraman Mebius. In Zamsher's novel, it was revealed that the racial conflict was a competition to secure their position as one of Alien Empera's forces. Earth monsters : The first monster to be awakened in 1971 due to a mysterious phenomenon surrounding Earth. In addition to consuming oil, Takkong can also spit them from its mouth. Takkong killed Zazarn in its awakening and played an indirect part in Go's encounter with Ultraman Jack by attacking the building he was in. The day after Arstron's death, Takkong targeted various supply ships and consume oils from a nearby petroleum complex, threatening the workers inside. It was killed by Jack's Specium Ray after several amputations. : A sea monster consist of poisonous seaweed sludge. It fought against Takkong nearby the Sumida River and was killed after its seaweeds dried