From the union of Gaia and Uranus came the 12 Titans, the prior gods. First born was Cronus but the three sons that followed were malformed monsters, each with but a single round eye in the middle of their foreheads, the Cyclopes. The next children produced by Uranus and Gaia were uglier still with fifty heads and a hundred arms, Hecatoncheires.
Uranus was so appalled by the sons born of this union that, one by one, he took them and hid them from the light of day.