King Ghidorah is one of the most famous recurring monsters in the Godzilla franchise, known as a giant three headed dragon like kaiju. The character first appeared in Japanese Godzilla films in the 1960s and has returned in multiple eras of the series, including modern movie adaptations. Online, the King Ghidorah roar is popular in kaiju edits, versus videos and meme clips because it immediately communicates a stronger, world ending threat than a normal monster sound. That clear association keeps it widely reused.