Saeko Kanagusuku: “Of course! It's the guardian of the Azumi family, King Caesar.”

Keisuke Shimizu: “King Caesar?”

Saeko Kanagusuku: “It's the one treasure of the Azumi royal family. It is handed down by tradition. Anyway, a legend states that the people of the mainland tried to conquer the Okinawan people. A brown monster came forth and began rescuing the royal family and their subjects. The monster's name was King Caesar.”

― Saeko Kanagusuku identifies a statue of King Caesar found in a hidden cave (Godzilla vs. Mechagodzilla)

The ancient guardian of the Azumi royal family of Okinawa, King Caesar could only be awakened by a mystical statue. The Black Hole Planet 3 Aliens attempted to recover this statue so that King Caesar could not stand in the way of Mechagodzilla, but their attempts failed when Saeko Kanagusuku and a group of humans used the statue to awaken the guardian monster. King Caesar attempted to battle Mechagodzilla, but was outmatched by the mechanical monster. Thankfully, Godzilla arrived and aided King Caesar in the battle. Together, the two Earth monsters successfully destroyed Mechagodzilla, after which King Caesar returned to his slumber in a cliffside at Cape Manzamo.