Hearthpwn

I created this new Zoo Mech deck when I realised the new potential of Zoo to spiral out of control. It's a certainty that this deck (in some variation) will hit the scene as soon as the expansion comes out.

 

EDIT: Soulfire at 1 mana is a good card, still. Yet I wouldn't keep it in my opening hand anymore, because it costs 1 mana and we need that mana for developing the board.

EDIT: I did some play-testing and I think Cogmaster doesn't perform as well as thought. It's only a good card on turn 1 and decent if protected by Annoy-o-Tron, but ceases to be valuable otherwise. Afterwards I did some testing with Micro Machine and it suffers from exactly the same problem. So I put in Loatheb and Ironbeak Owl, as originally suggested. Possibly a single Tinkertown Technician is reasonable instead of either Loatheb or Ironbeak Owl.

 

Replacements

Replacement 1:

Clockwork Gnome. Undertaker is incredibly strong already, but now we have a neutral 1 Drop mech synergy option that is not Leper Gnome: Clockwork Gnome.

Replacement 2:

Annoy-o-Tron is an expensive Voidwalker, but can be really good for stall in even late-game circumstances requiring 2 attacks. Mech Synergy is very valuable, think protecting Cogmaster (turn 1 play), while giving it +2 attack with Annoy-o-Tron makes it arguably better than Voidwalker now. Also there are so many 1 drops Voidwalker has to compete with in this deck, it usually wouldn't cut it anyways.

Replacement 3: 

Mechwarper facilitates all our mech so much quicker and will allow us to drop several 2 drop mechs at a time and Clockwork Gnome for free. Anything deadly will be out so much earlier. I reckon it replaces Nerubian Egg, which has always been on the weaker side of Deathrattles, requiring activation, which we now lack due to the inclusion of more mech, such as Piloted Shredder instead of Dark Iron Dwarf and Enhance o-Mechano instead of Defender of Argus. Also Deathrattle Zoo can now perform without Leper Gnome or Zombie Chow due to the inclusion of mech card Clockwork Gnome. But if you are more of an Aggro Player, feel free to play Leper Gnome or perhaps even trustworthy Deathrattle Zombie Chow instead of it.

Replacement 4:

Enhance-o Mechano. I thought about under which circumstances I would (heavily) prefer Defender of Argus over Enhance-o Mechano and there aren't really many. Also most of those scenarios I would likely lose still, because when you need taunt to protect the face, Zoo has usually run out of steam already. Anyway there's a good chance of hitting at least one Taunt, at least, as each minion individually has 1/3 chance to get one of 3 effects. (i.e. when you have, say 3 minions, chances of hitting at least 1 effect, be it Taunt/Windfury/Divine Shield are 1-(2/3*2/3*2/3) = 19/27 ~ 70%). So I think Enhance-o Mechano can outvalue Defender of Argus in Zoo. It's windfury to the face / better trades with Divine Shield / some Taunt, so Defender of Argus without the +1/+1 (so slightly worse sometimes). Also it's another Mech.

Replacement 5:

Piloted Shredder replaces Dark Iron Dwarf. Sure, trading up with Dark Iron Dwarve's +2 buff is nice, when you have a minion on board. That however may not be the case. Piloted Shredder is a much more stable minion on the battlefield with Deathrattle, making it a bigger version of Harvest Golem) and pretty much immune to board clears.

Replacement 6:

Cogmaster. Basically a Flame Imp without health loss in a deck with early mechs this card just had to find it's way into a Zoo Deck, as it trades up any time. It is an additional 1 drop over traditional Zoo Decks, that comes at the loss of situational cards, such as Loatheb and Ironbeak Owl, because there really is no space left for those cards at the moment.

 

Card Talk

Expansion Cards that were not included, but seem reasonable are: Micro Machine, Tinkertown Technician and Mimiron's Head. I believe that you could include all of those in an all-out Mech Deck, yet it doesn't feel as consistent as this mixed version with more stable Deathrattle minions.

My reasoning is the following:

Micro Machine is really good, when it's protected by Taunt. Otherwise, I reckon it's more often a 2-2 for 2 that will trade unfavourably for us on the opponent's next turn, than anything else.

Tinkertown Technician does not add something to the board immediately, except for itself, unless you get a Spare Part you need, assuming you also have 1 more mana.

Mimiron's Head is definitely a bit gimicky (win-more-card) and should only be played in conjunction with the aforementioned cheap mech-cards.

Ironbeak Owl and Loatheb also seem reasonable, but one must look really hard for something to cut to put those meta-cards in.

 

Summary:

Overall this deck reminds me of the very first iterations of Zoo decks (pre-Naxx, of course), when a mix of Murlocs + early drops was played. Yet this one feels better still, because of the synergy between mech cards, such as Clockwork Gnome, Harvest Golem and Piloted Shredder with Undertaker.

 

Edit

If you are interested in a more mech-heavy Zoo, I also have this deck to offer:

LINK