Hearthpwn

Well rounded control/combo deck including Big Spells Mage shell, some deathrattles and a surprise bang at the end. 

Edit 1: Added Loot Hoarders and N'Zoth, the Corruptor old school Kripp style to get to the combo faster and get a nice tempo swing also.

Edit 2: Replaced Arcane Artificer with Arcane Keysmith. I like it more because of its flexibility - it can help you with value, removal, disruption.

Showcase of a hard fought win against Big Priest, the Combo and usefulness of Echo of Medivh: https://hsreplay.net/replay/iFZSLRbgXqm4Eeg39jfm7R

Win condition

• against Aggro - remove their minions, put some taunts in their way, heal with Frost Lich Jaina or Arcane Artificer. Board clears should be aplenty - especially Dragon's Fury is MVP.

• against Control - probably the toughest matchup. This is an attrition game - Frost Lich Jaina is hugely important. Polymorph their important minions. Time your Dirty Rats with AoE. Try to win the board so that your Ragnaroses can finish them off. OR depending on the deck outvaluing the opponent and winning in fatigue is possible.

• against Combo - Wait for them to be almost able to have the full combo and then Dirty Rat them. You can also use Brann Bronzebeard and Zola the Gorgon to get more rats.

The Combo

Set up: Emperor Thaurissan discounting all 3/4 pieces, 8 damage with HP dealt this game, should be easy with Frost Lich Jaina

Sequence: Brann Bronzebeard - Jan'alai, the Dragonhawk - Zola the Gorgon on Jan'alai

Result: 2x Ragnaros the Firelord in play + 2 more in hand ready to follow + 16 immediate damage + 16 healing with Jaina + menacing board

+ Echo of Medivh - to get at least 2 more Rags. You can freely use this card for other plays.