The Hecatonchires are a set of xenoform triplets related to the Olympians. They are children of Ouranus and Gaia. Named Briareus, Cottus and Gyges, they each have many arms and many heads. They were banished by their father and, despite aiding Kronus in overthrowing Ouranus, were cast back into Tartarus by the Horned King. Zeus freed them when he defeated Kronus and tasked them with guarding the gate of Tartarus.