Hyades was the ancient Greek chthonic god of the underworld, which was given Hyades name. Greek mythology, Hyades is the oldest son of Cronus with Rhea, being the last son regurgitated by his father. Hyades with his brothers Zdeus, Poseidon, defeated their father's generation of gods, the Titans, claiming rulership over the cosmos. Hyades rules the underworld, Zdeus rules over the air, Poseidon rules over the sea along with the solid earth