Gamera is a kaiju originating from a series of Japanese tokusatsu films of the same name. Gamera first appeared in Daiei Film's 1965 film Gamera, the Giant Monster, which was initially produced to rival the success of Toho's Godzilla.
Vote which fictional character would naturally fit in-universe with a big-named franchise! No time-travel, no interdimensional crap, no "Pooh's Adventures", they would just exist in-universe.
