Getter Emperor is a massive Getter Machine existing in the far future. It represents the unstoppableness of Getter Rays and becomes a threat to all life in the universe. It has yet to have made a full anime appearance, though it has had cameos in both Getter Robo Armageddon and New Getter Robo.
Getter Emperor also made an appearance in Getter Robo Anthology~Will of Evolution~. He appears in chapter 1, 2, 4, 5, and 6. In chapter 1 he appear in a vision during a battle between a new Mecha Saurus and the original Getter team.  In chapter 2 the Āḥ team from Getter Robo Āḥ while battling a unknown Getter Robo also saw Getter Emperor.