Hearthpwn

Yeah the combo is Mecha'thun and Plague of Flames with one discount. Or you can run Bloodbloom, Cataclysm, Mechathun, requiring one more card and one more discount, but destroying your hand. The point is that the deck can win against faster decks by clearing their board and playing demons, but if its against a slower deck then you can kill off Mecha'thun instead. Once you have your combo, but your deck isn't empty yet, you can play Soularium to turbo draw into your remaining cards and combo a few turns earlier. If you're in a slow matchup, like Control Warrior, 2500 Armor Druid or a Reno deck, the Mecha'thun is a great way to win.

genious deck (no)! and how it is is supposed to activate Mecha'thun ?! 

Emperor -> Plague of Flames + CThun? 

after that combo-wombo your hand must be empty. That situation is a little less than completely impossible with soularium and slow expensive stuff