"He amassed an army of Nobodies and worked to release increasing numbers of heartless on many worlds. He then manipulated the keybearers into fighting the heartless - not difficult, since the other option was letting them run rampant - and ensured that the released hearts were trapped in a false Kingdom Hearts that would serve as a gateway to the true one." Ienzo sighed. "I don't know if you are familiar with Radiant Garden, but he started there."