Redking first appeared in episode 8 of the original Ultraman television series, The Lawless Monster Zone, which aired in Japan in 1966. The skull-faced kaiju became a fan favourite thanks to its brute strength and the famous scene where it hurls boulders at its enemies. Its roar was reused across later Ultra series, cementing it as one of the most recognisable kaiju sounds of the Showa era. Online it lives on in tokusatsu fan edits, monster ranking videos and meme clips that need a genuinely fearsome roar.