Hearthpwn

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Twitter: @RazorHearth
Youtube: youtube.com/razorhearth

Still working on this guide, more updates soon...

Playstyle

It is important to understand that this deck is a tempo deck and is not really a face or combo deck. The main idea with this deck is that you continuously play cost-efficient minions and weapons that make it progressively harder for your opponent to compete on the board, while also introducing ‘recurring’ threats that give you additional value or utility each turn it remains in play (Warsong Commander, Jeeves, Frothing Berserker, Hobgoblin, Mechwarper). The end result is that your opponent eventually falls behind and can’t kill all the recurring threats, allowing you to gain substantial advantages from the ones that stay live. As a result, a lot of this deck is about making smart and efficient trades rather than being straight up aggressive.

Mulligan Strategies

Because of the various synergies in this deck, mulligan priorities shift greatly based off of what's already in your hand and whether you're going first or second. That said, here are some broad strategies (in order or priority):

Mech Mage - Fiery War Axe, Cogmaster, Mechwarper, Warbot
Oil Rogue - Fiery War Axe, Death's Bite, Mechwarper
Face Hunter - Warbot, Mechwarper, Annoy-o-Tron, Cogmaster, Cruel Taskmaster, Fiery War Axe
Ramp Druid - Mechwarper, Fiery War Axe
Shaman - Cogmaster, Mechwarper, Fiery War Axe
Zoo - Fiery War Axe, Cogmaster, Mechwarper
Priest - Fiery War Axe, Death's Bite, Mechwarper
Paladin - Cogmaster, Fiery War Axe, Mechwarper
Control Warrior - Annoy-o-Tron, Mechwarper, Fiery War Axe

Match-up Strategies

Face Hunter (+60%) - The key to this match-up is contesting the early game. Warbot and Cruel Taskmaster are excellent responses to turn 1 Leper Gnome and an early Annoy-o-Tron or Mechwarper can gain you a lot of tempo. Don't be afraid to take a little more damage in the first few turns to secure a stronger board state, you'll take less damage later on because of this. Their main catch-up play is Knife Juggler - Unleash the Hounds so if you can force either of these cards out independently, you're in great shape.

Oil Rogue (~50%) - Contrary to what my stats suggest, I do believe this is one of the most difficult match-ups. You tend to want to play this match-up much slower, often opting to not play your 1 or 2 drops unless you feel they can stick or get a little more value (like waiting until turn 3 to play Mechwarper + Annoy-o-Tron as opposed to playing Mechwarper turn 2). Because of this, you mulligan for weapons to control the early game until you can drop stickier threats (Piloted Shredder, Hobgoblin + Warbot/Annoy-o-Tron/Cogmaster). Death's Bite is critical for keeping Violet Teacher under control. The card you are most scared of is Blade Flurry. The main goal of this match-up is to put pressure on them while making Blade Flurry as inefficient as possible. Oftentimes, if Blade Flurry fails to full clear, you're probably going to win the game.

Control Warrior (~60%) - This match-up is played slower than most unless you have a very explosive Mechwarper opener. The main idea is to multiple threats in one turn to make their Fiery War Axe less effective. For example, instead of playing turn 2 Mechwarper, you might want to play turn 3 Mechwarper + Mechwarper/Annoy-o-Tron. Similarly, instead of playing turn 1 Cogmaster, you often will play turn 4 Hobgoblin + Cogmaster instead. Between Warsong Commander, Hobgoblin, Acolyte of Pain, Frothing Berserker, Mechwarper, and Jeeves, the opponent will often be extremely taxed for removal and you can often posture to play a Jeeves for multiple cards that can't be removed immediately easily. Because of this, you're actually able to often survive and compete into the late game and don't need to feel pressured to go all-in early every time.

Mech Mage (+60%) - You have as many ways to contest the early game as they do, if not more. Weapons can buy you a lot of tempo and your early drops can make Annoy-o-Tron and Mirror Entity a lot less effective. You should favor towards clearing your opponent's mechs every turn as it makes it difficult to play their main tempo building card, Goblin Blastmage. Warsong Commander is an MVP in this match-up because you create extremely efficient clears. Their main ways to win are to either have an explosive start that you can't deal with which tends to be rare, or to deal just enough damage early and Fireball you to death (typically with Antonidas) before lategame kicks and you can Hero Power out of range.

Deck Modifications

Dr. Boom can be replaced by Piloted Sky Golem or Emperor Thaurissan or Hogger
One Execute can be replaced by Loatheb if there are a lot of Rogues
Armorsmith is worth adding if there are a lot of Face Hunters

The following are generally worse or untested but worth trying:
Micro Machine
Junkbot
Demolisher
Haunted Creeper