The Doctor shook his head. "No. He's worse than that. He toys with people - mind-games - and his mind is insane so they're insane games. And he kills without a second's thought. A version of him killed at least twice last time I was here - fortunately both victims were people who could get up again, but who knows what effect it had on the timeline, having a Time Lord go home regenerated? Please, just... don't mess with him."