After skimming through the sea of individuals arguing that because Kronos wasn't at his peak, the fight between Persephone and Kronos wasn't particularly good. Being the Titan of Time and having ten years to develop his strength, Kronos now has the ability to control nightmares. Instead of Persephone being an absolute unit of a Mary Sue, the fight ought to have been evenly matched. Even if Kronos returned, what would be different? Would there be a 20-year time leap and him at his peak of power? Rachel would never permit Kronos to exploit Persephone's fertile goddess powers, and there are no other goddesses for him to employ as a source of power.