Mechagodzilla (I)

Mechagodzilla is a giant robot mecha whose form and function is designed to be similar to that of the daikaiju known as Godzilla. Played by "suitmation" actor Ise Mori, it appeared in the 1974 film Godzilla vs. Mechagodzilla.

Overview
A race of aliens who hail from a planet within a black hole set their sights on conquering Earth. To dispose of the planet's greatest threat, Godzilla, they constructed their own artificial robotic version of the creature dubbed Mechagodzilla. Housed within a synthetic skin covering to look like the real Godzilla, this mecha was sent to Earth and began razing Japan, until the real Godzilla appeared and burned away its false covering with his atomic breath, exposing the true robotic visage underneath. After which, the battle began in earnest.