Kronos

“And yet, you tried to stop its coming. By locking me away in Tartarus along with my Titan Generals, you only prolonged your end”

Kronos was the youngest of the first generation of Titans, and Lord over Time. He overthrew his father, Ouranos, and Kronos castrated him using his scythe. As Kronos bore the Gods with his Wife, Rhea, he feared their revolt against him and the titans, and so as each was born, he ate them. Rhea, fed up with Kronos, hid away Zeus and replaced him with a rock, which Kronos mistakenly ate instead. Zeus revolted, and freed his brothers and sisters. He and the Gods fought the Titans in the Titanomachy, the first war between the Gods and the Titans. Zeus defeated Kronos and imprisoned him and the other titans in Tartarus. For ages, Kronos has remained, unable to escape.

He has, however, been able to stretch his influence out into the world through minute cracks in Tartarus. It this way that he ensares Aaron to set him free. Kronos frees two other Titans, Typhon and Asteria, knowing that after all these millenia, they were all he'd need. He succeeds in overthrowing the Gods, but to his surprise, just as he is about to claim the throne of Olympus, it vanishes along with the rest of Olympus. Kronos concludes that one of the Gods is still alive, and has stolen Olympus away. He'd have to defeat this God to gain control. Thus he devises a plan to draw the God into the open. To his surprise, he finds not only a god, but five.