 However, fearing an oracle which foretold that his own children would rise up against him, Cronus had swallowed each of them as they were born, except his son Zeus, whom Rhea had saved.When Zeus reaches manhood, he frees his brothers Poseidon and Hades, and Gaia's imprisoned children.Together, the Olympian Gods and their monstrous allies defeat the Titans, who are imprisoned in columns of stone in Tartarus.