Can any Transformers fans who are also big hardcore fans of robots in Japanimation, please name what you consider is as the tallest giant robot in Japanese only anime ( be it anime film or anime TV). Any robot Transformers characters are EXCLUDED. My own view is that it's Diebuster, also know as Gunbuster. Other possible candidates are below. Deucalion (32000 kilometres). Not sure about it. I understand the mecha Ideon and the Daitarn 3 (old school) are also very huge. SDF-1 from Macross ?. This doesn't really count, as SDF-1 is more of a battleship, that just sort of looks like a robot. Shin Dragon from Shin Getter Robo is pretty huge. Shin Getter by comparison is almost twice the size as Getter Robo. Shin getter often stands on top of Shin Dragon's forehead. Devil Gundam from G Gundam ? The Big O, Voltron ?