The Guardian of Space

 Giant robot Daikengo flies through space to re-establish galactic peace; on-board prince Ryger, who ran away from his planet Emperius to defeat the menace out of his reign borders, in order to save his people; Cleo, corrupted prime minister's daughter, help him along with two nice little robots, Anike and Otoke. They fight evil Lady Baracross, leading invasion forces, with her assistant Roboleon, wearing a Napoleon style hat. Daikengo is the first robot with scuttles on his mouth. When he opens them, his vampire style teeth are shown and he can spit fire.

(Source: Anime News Network)