Hearthpwn

May 2019: Climbed with this deck. Started at Rank 20 and in 3 days managed to reach Rank 2, 5 stars with a rather consistent 70% WR from 20 to 5 and 60% from 5 to 2

Sep AND Oct 2019: Reached Rank 5 from Rank 7 with a 7 game winning streak.

In my history of playing this deck, I'm at 271-206 (57% WR)

This deck is really simple to play; It's basically using card draw to find the OTK Combo.

OTK Combo: Archmage Antonidas + 2 x Sorcerer's Apprentice + 2 x Molten Reflection = UNLIMITED Fireball

Total Mana Cost: 14

Use Emperor Thaurissan when you have at least 4 of the OTK pieces in your hand to reduce the mana cost needed to 10.

Starting Hand

Without Coin: You'd want to have at least 1 of the 2-cost card draw cards; I personally rank them in the following order:

1. Mad Scientist
2. Arcanologist or Novice Engineer
3. Research Project

It would be great to have the 3-cost card draw cards as well:

1. Arcane Intellect
2. Coldlight Oracle

If you suspect you're against Aggro (e.g. Odd Paladin/Hunter/Warlock), might want to consider having Doomsayer (If against Shaman, they usally have Devolve, so I'd advise against it)

With Coin: You'd want to have at least 2 of the 2-cost card draw cards; I personally rank them in the following order:

1. Mad Scientist
2. Arcanologist or Novice Engineer
3. Research Project

Use Coin on Turn 1 to play one of them, then play the other one on Turn 2. Even if you don't have two 2-cost card draw cards, it's a good idea to make this move anyway to

• Gain some board control
• Possibly draw the second one

It would be great to have the 3-cost card draw cards as well:

1. Arcane Intellect
2. Coldlight Oracle

Tips:

1. Try not to overdraw
   • If you have 9 cards in hand, don't play a card that lets you draw twice, unless you can play another card
   • Only time I'd confidently overdraw by 1 is if I have not many better options, I already have both Emperor Thaurissan and Archmage Antonidas and I'm searching for the other OTK pieces.
2. Frost Nova or Blizzard + Doomsayer works wonders, but
   • It's good to have a backup plan in case your opponent clears the Doomsayer so you don't panic as much
   • An early Doomsayer by itself against Aggro opponents might be the key to maintaining board control. Consider it if:
     • Your hand is awful, not sure if you can handle getting hit for 5-10 each turn for the next three turns
     • Your opponent has around 2-3 attack on the board, but could possibly become >7 if you don't play Doomsayer
     • Your opponent is unlikely to have a card to clear Doomsayer
3. Coldlight Oracle or Research Project against opponents who already have many cards in their hand is always a fun to watch. Especially important if you suspect your opponent might be playing a combo deck; try to mill their combo pieces away. On the other hand, if you're up against Aggro who has limited cards in hand, don't feed him into choices.
4. Be wary of cards which could remove one of your OTK pieces: Deathlord, Gnomeferatu, Dirty Rat and take note of opponents such as Mill Druid or Mill Rogue
   • Try to have <8 cards in your hand
   • Let your opponent draw your cards for you
5. Luckily for us, we have Simulacrum, which is a secondary option when:
   • Your Sorcerer's Apprentice or Molten Reflection is accidentally milled
   • Your Sorcerer's Apprentice or Molten Reflection is not getting drawn
   • Make sure that no other 2-cost minions are in your hand when you use this card, else it's up to chance
6. Playing Emperor Thaurissan when all 5 OTK pieces are in your hand reduces the OTK cost to 9. This could be important if you don't have much health left, on Turn 8 and all the cards are in your hand.
7. Arcane Artificer can be used for the following:
   • Early-game board control (However, this should not be your priority in most games, card draw is still the key. Possibly against Aggro it might help, but I wouldn't recommend) 
   • Gain some armor mid-game to delay popping of Ice Block
   • Build up a safety net after Ice Block is popped
   • Low-cost card to play out if hand is near full (Should still try to gain some advantage of it, such as playing it together with a secret or Arcane Intellect
8. Even with Ice Block, you are susceptible to dying due to fatigue. Make sure you have >1 card on the OTK turn or you have >1 health. Conversely, if you happen to play against similar decks, reduce them to 1 health when they are about to fatigue to go around Ice Block

(UPDATED) Match-ups:

(In general) Against Aggro (Murloc Shaman/Mech Hunter):

1. Try to have early-game board control through Mad Scientist,Arcanologist, Novice Engineer
2. When they have board control, clear the board using Frost Nova + Doomsayer or Blizzard
3. Freeze the board only if necessary (i.e. If there's only <10 attack on the board and you're on 30 health, card draw should take priority, especially if you have one or both secrets in play)

(In general) Against Control (e.g. Renolock/Handlock/Reno Mage):

1. Card draw
2. Win game

Against Odd Paladin:

• Their counter to Doomsayer is Ironbeak Owl, which cannot be played on a full board. Once their board is full, Frost Nova + Doomsayer should make it a manageable game.
• If you can choose between two minions to clear, clear the Silver Hand Recruit as they have other cards to buff it.
• The secret most usually run is Never Surrender!, so no need to be too worried about Noble Sacrifice or Competitive Spirit. Most of the time when the secret is played, I don't even bat an eye

Statistics

From Rank 20 to Rank 4, I'm on 59-21 (74%), the losses are mostly due to tempo decks having really good tempo + poor opening hand or losing out to other OTK decks which go around Ice Block (e.g. Mill decks)

Why I've been successfully is highly due to the Priests and Warlocks on ladder. I'm 21-1 against Big Priest. Jade Druid is usually a pretty successful match-up as well.

Summary

This deck is a card-draw deck which is rather simple to master. Just draw nearly your entire deck until you have OTK pieces and you win. Board control doesn't even matter because your opponents minions can be frozen and whatnot.

*Try not to bm your opponents when you do win in the end because it's rather frustrating for them to lose like that.