"Bad dream." He felt immediately embarrassed, admitting that, but it didn't matter, really. Jack wasn't about to use that against him (at least, the Doctor hoped not).

"Dreamt about the Ood."

Something was nagging in the back of his mind. He'd been running from the Ood for so long, he'd almost forgotten just how powerful they could be. Powerful enough to call him, powerful enough to send dreams to him.

A ready-made psychic army.

"I think I've figured out how to reset the timelines."