S04E24: The Warriors of the Water Star!

Potomuri appears before Earth Eleven and reveals the truth about him and Mizukawa. He has been controlling Mizukawa's body since the time he used the last of his power to save her. He also reveals that Kiel was ruined by a black hole. Tsurugi, who got kidnapped, is brought to Faram Obius to meet queen Lalaya. He then gets proposed to become Lalaya's husband.