Hearthpwn

Mulligan

Keep cards like Doomsayer, Deathlord and/or [card]Twilight Flamecaller[/card] to destroy his plates very fast at the early stages of the game. Dont be afraid to play Coldlight Oracle, he will draw enough cards anyway, but the carddraw will help you a lot.

Deck Idea

Keep the board clear with your massiv aoe-spells and aoe-abilitys of your minions as well as with your synergies, try to trade efficient. Sooner or later he will die to fatigue or you can hit his face with our surviving minions.

Keep in mind that it will always trade in as long as his minions dont die. For example you can play Deathlord and Doomsayer on a full enemy board. It will trade his minions into your Deathlord, a random minion of his deck get summoned and Doomsayer will destroy it right at your turn.

Synergy

Flamewaker/Wild Pyromancer -> nearly every (low) spell
Deathlord -> Doomsayer

Good Luck !

Proof/Howto-Video