Hearthpwn

I'm going to try this out for fun.

Any tips for the mulligan?

Yo!  Try the current list out if you're still interested; I made a few changes.  Darkshire Librarian and Silverware Golem seemed silly to leave out.  It's a bit more RNG-heavy now as the discards can really matter a lot but the quest gets finished by turn 7 usually, sometimes turn 6!  Before it was turn 8 which is when Primordial Drake hits the board haha. 

I'd suggest mulliganing for Malchezaar's Imp, Voidwalker, Mortal Coil and Darkshire Librarian. Demonfire and Bloodfury Potion have often been good plays on curve for me so long as I already have a demon out but I wouldn't prioritize them for a mulligan.    Hellfire is good to keep in certain matchups.

It's fine if you don't have anything to do turn 1 and 2 because the quest and Life Tap are always available.  I would never pitch the quest unless I were psychic and knew without a doubt that I was about to play against Pirate Warrior.

Alright so Voodoo Doctor isn't that good haha.  The deck needs more beefiness, demon synergy and not-the-face than they can provide alone.  Their minion healing is nice but this deck isn't about humongous minions and keeping them alive - it's about killing the other guy!  And it does that pretty well with the help of some value cards like Crystalweaver and Second-Rate Bruiser - neither of which are comfortable to run 2-of in this deck but are both powerhouses in their own right.  

Stomped 3 meta decks in a row last night!  Finished all of them off with Hellfire.  Mwuhahahahaaa.

I've played some more with it and decided to make a couple more changes; the deck's still very fun to play but some cards are begging to be in this deck that are not in it yet.

Removal is so important in this deck: Hellfire is a key card without a doubt.  There's not enough deterrence in this deck for Corrupting Mist to not cost the deck 15+ health before the next turn by midgame!  Maybe there's room for both in some other Warlock deck but for this one in particular Hellfire is absolutely a must-have and takes priority.

I took one Silverware Golem and one Succubus out to make room for Dirty Rat, an amazing card all around in this meta.  He's powerful lategame coupled with hard removal effects as well as early game when the deck's in a pinch!

I still like the Voodoo Doctors too much to remove them - they're comfy and easy to play in a deck like this with big minions, minion buffs and draw power - but I'll see how they do on ladder.

Best of luck if you try this deck out!

Just played with this deck some again and I really like it haha.  The demon buff cards and the 6 hard removal spells is what makes me appreciate this deck, not to mention the portal which practically wins lategame on its own.