I'm calling it now. This + Shadowborn Apostle (M14). Sacrifice 6 Apostles to search and place any Demon from library to battlefield, then cast just one more Apostle to get them all back and search again. Rinse and Repeat.

Hmm, 1 black mana to play any Demon card from my deck, and ridiculously repeatable? YES PLEASE!

Edit: Sac the Apostles for a Rune-Scarred Demon, thus letting you tutor for this.