Nice guide, having trouble with Shadow Sifter myself. I'm sure the only champion nightmare I havent seen is the rat, am in process of trying challenge modes now but no luck so far.
Edit - Nevermind got it! Found doing the challenge "balancing act" would get more champion nightmares to appear as opposed to "champions among us".
Last edited by saintdave; 12-18-2012 at 10:20 AM.