Gigan first appeared in the Toho film Godzilla vs. Gigan in 1972 as a cyborg space monster controlled by aliens and sent to invade Earth. He later returned in Godzilla vs. Megalon and Godzilla: Final Wars, becoming one of Godzilla's most recognisable rivals. His metallic roar was shared online through kaiju fan edits, monster compilations and soundboards, where a louder version became popular for memes and edits. Its sharp, mechanical tone still stands apart from other kaiju cries, which is why creators keep using it for dramatic monster moments.