Hearthpwn

Averaging 65% winrate in rank 5 to legend with this deck, since it's rotating out in a week guess i'll share it. 

The most important thing about this deck is to keep having gas. You don't want to be left top decking unless youre looking for that last burn for lethal. It's easy to play everything in your hand in first few turns and have nothing left. It's also easy to use spells for killing minion in mid-end game when you should really be burning your opponent, as they will most likely outvalue you in minions (jades, dragon priest, renolock). 

Mulligan: Wyrm, thalnos (for card draw), frostbolt, babbling book, arcane intellect. 

If you're facing pirate warrior, card draw doesnt matter and you need to assert dominance on the board first turn with wyrm and 2 drop minions ASAP. a turn 4 or 5 flamewaker with small spells can ruin them, and water elemental can pose a serious threat to freezing their face the whole game. 

Don't use barnes unless you have something to follow it up if you get archmage or flamewaker etc... unless you have nothing else to do.