Hearthpwn

Hello to everyone,

my name is Spikini, an Italian player who finished April EU ladder at #14, qualifying myself for the July Master Tour. I want to share the Zoo decklist which lead me to this result. This was firstly proposed by Gregoriusil, another italian player who finished #24 EU last month, and together we refined it till the current version. 

The concept of the deck is pretty straightforward: draw Imprisoned Scrap Imp, buff as many 1-drops as possible and do it asap. Then discard Hand of Gul'dan to refill your hand with your threats. When you have the imp on the mulligan it is really hard to lose, but in order to take into account every case I leave you a complete guide of the deck, class per class. In the rest of the text when I refer to Imprisoned Scrap Imp I will just say "Imp", when I refer to Hand of Gul'dan i will just say "Hand".

General mulligan
You always keep the Imp, it is the core card of the deck. When keeping the Imp try to mulligan for 1-drop and/or kanrethad in order to do a big tempo swing on turn 3/4. 
You almost always keep Hand. The only matchups in which you mulligan it is against Warrior and, depending on your hand, demon hunter
You always keep Hand if you also have either Expired Merchant or Nightshade Matron. Being able to draw as much as you can in the early guarantees you to find the Imp or just win continuously refilling the board. 
There are not big differences in the mulligan with or without the coin. I will explain the eventual ones in the class mulligan description.

General Gameplay 
If you have imp in the mulligan, you just play it asap and do not play any 1 drop before it awakens. You want to obtain the highest value from the imp. The only exception is when you are against Demon Hunter without coin and a part of the Imp you also have  Blazing Battlemage or Flame Imp. In this case you have to play one of these drops at turn 1 to prevent excessive damage in the early game. You always hero power the turn after you play Imp, both in t1 with the coin or in t2 without it. You want to increase the number of buffed minions.

Class per class mulligan and gameplay

vs Demon Hunter 
Mulligan 
Keep only Blazing Battlemage, Flame Imp
Gameplay 
If you play imp at t1/t2 you just play all the minions you play each turn. You usually need one turn of trades to take control of the board, after that you are the aggressor and DH has to answer to your threats. Usually you win at t5-t6.
If you do not see imp try to swarm the board as much as you can until turn 3, then try to hero power each turn to look for Hand and discarding cards. After turn 3-4 the imp becomes useless in this matchup, so do not play it if you have other choices. 
Matchup
60-40, good matchup for zoo but it is quite normal to lose it if your opponents finds early Altruis the Outcast or a lot of 1-drop in the first turns.

vs Rogue 
Mulligan
Keep any 1-drop which is not 2-1 in the stat-line. Keep also Kanrethad Ebonlocke if you have at least other 2 1-mana demons.
Gameplay
This is the matchup in which you need Imp the less. Rogue struggles a lot on dealing with a lot of small minions, and you can just hit enemy face for 5-8 damage each turn. Try to damage your 2-health minions to play around Backstab and Seal Fate. Play around Faceless Corruptor at t4, if it may lose you the game.
Matchup
Non-HL Rogue: 80-20. It just does not have the answers to your minions, they can win with a crazily good hand, early big Edwin Van Cleef or if your hands really sucks.
HL Rogue: 70-30. The matchup is still very good but when they have Zephrys the Great early the match becomes a lot more complicated. 

vs Warrior
Mulligan 
You only look for Imp. You can win the matchup only if you have the Imp. 
Gameplay
Risky Skipper is the counter of this deck, it deals 2-3 damages easily to every minion in our deck. If you have imp at t1 or t2 you can play a bit around it by trying to bait it with a small board (3-4 minions) and then try to win the next one. If you do not have the imp the only way of winning is play all the minions and hope that Warrior does not find it.
Matchup
30-70. Worst matchup for this deck

vs Priest
Mulligan 
Keep only Hand and Imp. This is the only matchup in which having Hand is more important than having Imp.
Gameplay
You win this matchup by spawning different boards, the point is to set up a board that each time leaves 1-2 minions damaged. The core card is Hand since it allow you to cycle through your deck, it is quite common to win against priest simply because it finishes the cards in his hands while you have a lot in yours.
Matchup
55-45. Decent matchup for zoo, even though depends a lot on the draw of Hand and the number of answers that the Priest sees through the game.

vs Mage
Mulligan 
Keep any 1-drop which is not 2-1 in the stat-line. Keep also Kanrethad Ebonlocke if you have at least other 2 1-mana demons.
Gameplay
You have to finish the match before turn 6. Reno the Relicologist, Blizzard and other stall/removal cards really destroy us. In this matchup having the imp is good but not necessary since the freezes do not care about the stats. Always play around Rolling Fireball at turn 5.
Matchup
40-60. I have only a few matches against mage, and a few of them were lost because of Puzzle Box of Yogg Saron at turn 6 with Dragoncaster.

vs Druid
Mulligan
 Keep only Blazing Battlemage, Flame Imp. Do not keep Hand
Gameplay
This matchup usually depends more on the druid than on our deck. If the see ramp and answers to our board we usually lose with Kael'thas or Glowfly Swarm. In every other case we just hit the enemy faces with buffed/non-buffed minions.
Matchup
60-40. Good matchup, druids lists do not run Starfall anymore, so they need to have every single removal to deal with the board.

vs Hunter
Mulligan
Keep only Blazing Battlemage, Flame Imp
Gameplay
Very similar to the gameplay against HL rogue. Hunter has only Unleash the Hounds to deal with big boards apart of Zephrys the Great. Also remember that some list plays explosive, so try to avoid losing the game because of it!
Matchup
70-30. Very good matchup for zoo

vs Warlock
Mulligan 
Look only for Imp.
Gameplay
You have to always control the board, no matter what happens it is just about controlling the board. Usually the player who plays Imp first wins.
Matchup
50-50. Mirror matchup

vs Shaman/Paladin
Never faced one of those, simply out of the meta.


That's all about this deck right now. If the community appreciates a lot this guide I may be thinking about including some videos about the gameplay.

See ya! 

EDIT:
At the following link you can see the gameplay of the deck performed by Gregoriusil when he made the list. There were a diseased vulture and 2 dark glare, in that list but the gameplay is really the same. Unfortunately it's in Italian, but I hope everyone can enjoy the gameplay anyway.
https://www.twitch.tv/videos/598327829?sr=a&t=242s