Mulligans
A deck very similar to the one played by Day[9]. This deck aims to control the game with the shadowform hero power and use a wide variety of healing abilities to offset the loss of the normal priest hero power. You’ve got Reno, Darkshire, Twilight Darkmender, and Twin Emperors to help you live longer. Then finish them with C’thun, Confessor Paletress, and Kodorider. Assuming they don’t just concede first to your amazing deck.
I’ve had a fair amount of success with this deck despite being a sub-optimal hearthstone player, and its just too dang fun.