Ancient King is a villain from One Punch Man. He originally only appeared in a single panel of the webcomic, but got an expanded role in the anime adaptation.

The Ancient King is the leader of the ancient Terror Lizard Clan, awakening from his slumber after sensing the defeat of the Subterranean King and the Sea King and resuming his plans to take over the land. The Hero Association, already prepared for his awakening, attack him with missiles to lure him into a large deserted area, where he is then confronted by Tatsumaki. He starts talking with her but is interrupted when Tatsumaki receives a call telling her to return. Annoyed, he stomps her but is surprised when she dodges the attack, but tells her only a meteor could defeat him. He starts charging a beam attack, but then a huge meteor dragged by Tatsumaki's psychic powers hits him, leaving only his fried bones behind.