Hearthpwn

53% WR Lock to Legend from D5

So the goal is to nullify the combo of various decks atm and win through the opponent having little to nothing left to do. It's a quite Reactive Deck not Proactive. To that end, we use cards like Theotar and Demonic Project to counter their incomming combos and use Corrupted Tickatus to destroy cards in their deck. 
While all the time trying to stay alive with lifesteal, armor and boardclear cards. 
Tickatus can be doubled with Felosophy or with Brewmaster.
Brewmaster can also be used to Return Gigafin after a boardclear if you have 10 mana.
Using Altar of fire can be a gamle, use it when you have more to gain than lose, you do have 40 cards.
Using Gnomeferatu or Altar of Fire after Big Priest has Illuminated is always smart.
Immolate can burn more cards with the help of Loatheb and Cult Neophyte in subsequent turns, well most of the times.
You can swap out Felosophy if you'd like (it's not super-necessary).
Good Mulligan cards against aggro (in general) are: Armor Vendor, Mistress of Mixtures, Touch of the Nathrezim and Defile.
Against Ctrl or Combo: Its good to have Immolate, Theotar or Demonic Project alongside Card Draws.
 

Good Matchups: Murloc and Shudderwock Shamans, OTK Rogues

50/50 Matchups: Pirate Rogues, Denatrius Ramp Druid, Mecha'thun Lock, Skelly Mage

Challenging Matchups but still winnable: Big Rogues & Big Priests, Secret Mages.

Hard Matchups: Mech Mages & Mech Paladins, Abyssal Curse Locks