Hearthpwn

This deck is mostly based around synergy with Gazlowe. It's a fun deck to play and it has a decent late/midgame. I runs tons of Spare Part generators and some good 1 mana spells.

 

Card Explanations

Earth Shock- Good card, especially against things like deathrattle hunter and other deathrattles. Also has great synergy with Gazlowe

Lightning Bolt - The only reason I chose this one of Crackle mostly because it's 1 mana and has synergy with Gazlowe.

Rockbiter Weapon - Mostly for the same reasons as Lightning Bolt except it also has synergy with Al'Akir the Windlord and/or Doomhammer

Clockwork Gnome - This is your one drop, it works very well with Mechwarper and it gives Spare Parts which is also very good with Gazlowe

Annoy-o-Tron - This card is just a solid 2 drop, it works well against aggro and is just overall irritating to play against.

Mechwarper - This card is just good. Some people say it's the best card in GvG as a whole. It has amazing potential to let you pump out early cards. It also works great with Clockwork Gnome because it suddenly becomes a 0 drop, which is great.

Powermace - This is another great card, one more mana than a Fiery War Axe that give +2/+2 too a random mech? Great. It works great with clear and has awesome synergy with Arcane Nullifier X-21

Hex - This is basically the best removal card in the game. The only reason I cut one is for the one ofs like Big Game Hunter and Arcane Nullifier X-21, I wanted to run both so I cut a Hex. In theory you should be winning early enough that you don't need two. Just remember to trade before you hex.

Lightning Storm - This card is very vital. Against things like Hunter, Zoolock, Mech Mage, and the mirror, this card can make or break the game. That's why there's two. The other option is to cut one for another hex, but personally I think this is better.

Big Game Hunter - This card is incredible. I put this in almost every deck I own. He can just 1 shot all the giants, Ragnaros the Firelord and Alexstrasza. He also takes out Sea Giant and Fel Reaver, both of which I've seen zoo run.

Harvest Golem - This card is great. It give 4 power and 4 toughness for 3 mana, which is great. It's also a mech which gives it great synergy with the rest of the deck.

Tinkertown Technician - This card is great, it's a 4/4 for 3 like a harvest golem, except you get the whole thing when you play it, with a spare part as long as you have a mech. Amazing.

Arcane Nullifier X-21 - I have considered 2 of these, because they're just that strong. If this comes out on turn 4 or 3 with a Mechwarper it can just dominate. Especially if you have a Powermace out, it becomes a 4/7 Can't be targeted by spells or hero powers. This is incredibly hard to get rid of, especially for aggro.

Mechanical Yeti - I love this card. The p/t is great, a 4/5 for 4 (good p/t are ones that add up to at least 1 + 2 times the mana cost, this one has 9 where 2*mana +1 is 9). It's like a Chillwind Yeti that has synergy with mechs and gives Spare Parts.

Fire Elemental - This card is really good. It's an amazing Shaman card. It's like you have a Lightning Bolt plus a 6/5 for 5 without the overload. That is amazing. Not only is it a good value minion, but it comes with a good value spell, for less mana.

Gazlowe - This card is great, it's also what the deck was designed around. a 3/6 for 6 is kinda meh, but when you add on whenever you use a spare part or any other 1 mana spell, get a card that has synergy with you deck, that approximately 1/6 of which are legendaries, it seems better.

Dr. Boom - This is what you call value. Besides Cenarius he has one of the best p/t ratios in the game. He's a 9/9 for 7 (3 more than what's good) plus he randomly does 2-8 damage. He's good and he is also conveniently the only 7 drop.

Al'Akir the Windlord - I like this card. I pulled him a long time ago and I have pretty much been playing Shaman ever sense. He has good synergy with things like Rockbiter Weapon and Flametongue Totem for loads of damage. He also has great clearing potential and works well with Whirling Blades and Reversing Switch.

Card Substitutions.

I'll give substitutions for most of the Legendaries and Epics and maybe a few of the rares.

Powermace - This is a very strong card, for just about any Shaman Mech deck. If you don't have it you might consider playing something else. However, if you really want to you could probably substitute it for a Stormforged Axe however, I would most likely put in Crackle to clear some bigger things.

Lightning Storm - This is really good. It's your only board clear against things like hunter and zoo. It's gonna really hurt if you don't have it, and you may consider and alternate version of mech that is more too the face. If you really want to place this deck without it, the closest suggestion I can make is Forked Lightning. Forked Lightning is a 1 mana spell that works with Gazlowe, and is pretty terrible. Some better options might be Explosive Sheep or maybe Unstable Ghoul.

Big Game Hunter - This card is really good. In a meta that is full of Giants and Dr. Booms and such he is amazing. However if you have to sub him out, you might want to run another mech. Most of the common ones are good, if you want more early game you could run a Cogmaster or a Micro Machine, if you want more early/middle you could run a Spider Tank or a Piloted Shredder and if you want more late game/sustain you could run an Antique Healbot.

Arcane Nullifier X-21 - Even though this is good, it's not really required. If you wanted something that has a similar effect you could run a Sen'jin Shieldmasta if you want more removal you could run another Hex, and if you want mech synergy you could put in one of the subs for Big Game Hunter above.

Gazlowe - Honestly if you don't have him you probably shouldn't be playing this deck. You could very well play another version of this deck, or probably Mech Mage, but this specific deck is more or less based around him. If you really like my list (for some reason) you could run Toshley if you have him, or another solid 6 drop like Boulderfist Ogre, Cairne Bloodhoof, Sylvanas Windrunner or maybe The Black Knight. If you want to stick with the mech theme you could run a Piloted Sky Golem, but honestly if you don't have Gazlowe, just find another list.

Dr. Boom - He is very strong, you see him everywhere right now. He's a really good craft right now, possibly only under Vol'jin. However if you don't have him you could runToshley, Neptulon, or if you're desperate a Stormwind Champion. Dr. Boom is very good though, and he's a recommended craft. 

Al'Akir the Windlord - Like I said above, I really like this card. If you don't have him, probably the best sub for him would be aDoomhammer, which would give you more clear, but less burst. If you don't have that you could go for something like a Whirling Zap-o-matic but they really don't really do the same thing.

*Honerable Mentions/Cards that are also good in a Shaman Mech deck that I just didn't have room for (and would be good to run in a non themed deck).Crackle, Flametongue Totem, Whirling Zap-o-matic, a second Hex, Doomhammer, Cogmaster, Micro Machine, Spider Tank, a second Arcane Nullifier X-21, Enhance-o Mechano, Jeeves, Piloted Shredder, an Antique Healbot.

**Also, a side note, the only reason I'm not running Toshley and/orNeptulon is because I don't have them. Feel free to sub out something like an Arcane Nullifier X-21 or something for one or both.

Mulligans

Usually good things to keep are gonna be most 3 or lower drops. This includes Earth Shock (mostly against Mech or deathrattle decks (so mage, hunter, preist and shaman usually)), Lightning Bolt or Rockbiter Weapon, generally you would rather use the Bolt, because Rockbiter has good synergy with other cards. You usually want one or the other against a mage or preist because of Mana Wyrm and Northshire Cleric. You also want Clockwork Gnome, Mechwarper, Powermace, Lightning Storm against Hunters, Warlocks, Mages or Shamans,Harvest Golem and Tinkertown Technician. If you have a Mechwarper you can generally keep one of your 4 drop minions. In early turns you usually just want to curve it out, and you generally save spare parts for Gazlowe unless necessary otherwise. A notible play is Turn 1Coin intoMechwarper and Clockwork Gnome, turn 2 Harvest Golem or Spider Tank (if you're running it) and turn 3 Mechanical Yeti or Arcane Nullifier X-21.