Hearthpwn

This is the deck I used just now to beat Majordomo Executus on Heroic. You play it like a normal mill deck, except that you do not attack Executus too much until he starts running out of cards. Once he is in fatigue, then you hit him with everything you have. When he drops his Molten Giants, hit with all your minions to get Ragnaros out and do what damage you can, then Vanish. Then you just start playing minions as fast as you can and deal what damage you can to him. Between attacks and fatigue, the 60 effective health goes down surprisingly fast.

The two most important things in this match up are saving your Vanish for the right moment, and using Gang Up properly. I used them on my Sunwalker and an Antique Healbot. I found the Sunwalker much more effective that the Sludge Belcher's since he has no silences and can't just one-shot it with a Lava Burst, forcing him to trade into it. The excessive Healbots are what I started dropping every turn once Ragnaros came out to both keep up my health and provide alternate targets for his Hero Power. I got a little lucky here since he spent his second turn as Rag playing a 10-mana Molten Giant so I dodged one Hero Power from him. It took me a few tries and tweaks before I could win, mostly because I was too quick to use my second Vanish. When I finally one, I was still at 20+ health and only 2 cards into fatigue.

There are a couple cards that could be traded out. The Sinister Strikes were there to provide extra burst to take out Ragnaros as fast as I could, but I ended up not needing them except as combo starters onces or twice. I also ended up not using Trade Prince Gallywix, and would probably be better off with a second Sunwalker. Also, believe it or not, Kidnapper saved me from a Core Hound at one point, so he was definitely useful (bounced him, then killed him when replayed).

Anyway, I normally don't like Mill decks, but I thought it would be fun to try something other than the OTK options listed in the guide right now :)