GIGAN - The Planet Destroyer
Gigan was a cyborg -- part animal and part machine, so he must have been an artificially created dakaijuu. Gigan had no fancy energy weapon (the laser beam in the poster was never used in the movie), but he managed to bloody Godzilla with his sharp claws, bite him with his powerful mandible and shred him with his saw blade abdomen. Gigan and King Ghidora were driven off by Godzilla and Angilas. I believe in a one-on-one battle Gigan could have defeated Godzilla.
In 1973 Gigan appeared in the movie Godzilla vs. Megalon, in which he was sent to assist Megalon and the Seatopians in trying to conquer the Earth.
Megalon and Gigan were defeated by Godzilla and the giant robot, Jet Jaguar.
In 1973 Gigan also appeared in The Roar Of Godzilla! -- episode 11 of the television series Ryusei Ningen Zoon (Meteor Man Zone aka Zone Fighter). Gigan was not at his best in the program, he was easily defeated. He must have been sick.
Gigan also appeared in some books in which he is given a laser beam, which comes from his forehead.
Angilas, Gigan, Godzilla, Jet Jaguar, King Ghidora and Megalon are © Toho E-B Co., Ltd.
Ryusei Ningen Zoon © 1973 Toho E-B Co., Ltd. & Mannen Sha Advertising Agency