Hearthpwn

Shudderwock Shaman runs Mind Control Tech and Grumble, Worldshaker. The entire draw of Hir'eek, the Bat is to summon large boards of his clones, and so a shudderwock deck can likely steal a couple and bounce them back to their hand at 1-mana. 

Dragon priest/warrior incoming...

Dragon Warrior was legit back when Alex's Champion was a card. I hope they print some great new dragons (also in neutral so priest can get in on the fun) to support this legendary.

Good card, wrong class. It would be extremely powerful in Warlock, Shaman, or Priest, but, as we saw with the paladin spellstone, paladin healing isn't always easy to achieve..

The order of operations causes them to shuffle the corrupted blood into their deck BEFORE they draw, thus the first draw of the naturalize draws the one corrupted blood in their deck (deathrattle triggers before naturalize resolves).

The thing is, Hakkar is likely completely unplayable in almost every other deck. It MAYBE could have a very niche spot in an armor warrior or heal priest (both of which just want to attrition the opponent to death), but it is even so that complicates those decks. Also, this card just screams for silence/transform because, if your opponent plays it, you know that they are using a deck designed to heal up and tank a game of mutual Russian roulette. You are correct about mirror matches, but that is likely uncommon in the cue (but not in tournaments).

Yeah, here is my prospective decklist for this combo: https://www.hearthpwn.com/decks/1197270-hakkar-the-soulflayer-king-togwaggle-instant-kill

Read my combo + explanation more carefully, specifically the bolded part: 

Put Hakkar, the Soulflayer in a mill Druid with two Dreampetal Florists and the Twig of the World Tree. Burn through your entire deck and then play King Togwaggle and either a discounted copy of this card or refresh your mana crystals to play this card at full cost and Innervate/Naturalize it. Because you naturalize it on your turn, this casts the first Corrupted Blood in their deck on YOUR turn, leaving two corrupted blood in their deck and dealing 1 fatigue to them. On their turn, their natural draw draws the first Corrupted Blood in their deck, dealing 3 damage and shuffling 2 copies into their deck, leaving them with 3 copies--this ensures that the draw chain IS INFINITE.

If this catches on, it could be really scary and difficult for many decks to deal with. Some decks can survive against mill druid, but this combo would kill any opponent, at any life/armor total, no matter what secrets they had in play (even if they had an Ice Block in wild).

Imagine putting Hakkar, the Soulflayer in a mill Druid with two Dreampetal Florists or the Twig of the World Tree. Burn through your entire deck and then play King Togwaggle and either a discounted copy of this card or refresh your mana crystals to play this card at full cost and Innervate/Naturalize it. Because the only card in your (now their) deck is the corrupted blood, it will endlessly draw itself and deal 3 damage, instantly killing the opponent. In effect, instead of using Naturalize or Azalina Soulthief to prevent them from switching back you just murder them the next time they draw a card (which is before they have a chance to interact with the board in any way).

If this catches on, it could be really scary and difficult for many decks to deal with. Some decks can survive against mill druid, but this combo would kill any opponent, at any life/armor total, no matter what secrets they had in play (even if they had an Ice Block in wild).

IMPORTANT - Before flaming me and saying that this won't work, read below:

Because you naturalize it on your turn, this casts the first Corrupted Blood in their deck on YOUR turn, leaving two corrupted blood in their deck and dealing 1 fatigue to them. On their turn, their natural draw draws the first Corrupted Blood in their deck, dealing 3 damage and shuffling 2 copies into their deck, leaving them with 3 copies--this ensures that the draw chain IS INFINITE.

Put Hakkar, the Soulflayer in a mill Druid with two Dreampetal Florists and the Twig of the World Tree. Burn through your entire deck and then play King Togwaggle and either a discounted copy of this card or refresh your mana crystals to play this card at full cost and Innervate/Naturalize it. Because you naturalize it on your turn, this casts the first Corrupted Blood in their deck on YOUR turn, leaving two corrupted blood in their deck and dealing 1 fatigue to them. On their turn, their natural draw draws the first Corrupted Blood in their deck, dealing 3 damage and shuffling 2 copies into their deck, leaving them with 3 copies--this ensures that the draw chain IS INFINITE.

If this catches on, it could be really scary and difficult for many decks to deal with. Some decks can survive against mill druid, but this combo would kill any opponent, at any life/armor total, no matter what secrets they had in play (even if they had an Ice Block in wild).

I don't know is this is viable or just a meme, but imagine putting Hakkar, the Soulflayer in a mill Druid with two Dreampetal Florists or the Twig of the World Tree. Burn through your entire deck and then play King Togwaggle and either a discounted copy of this card or refresh your mana crystals to play this card at full cost and Innervate/Naturalize it. Because the only card in your (now their) deck is the corrupted blood, it will endlessly draw itself and deal 3 damage, instantly killing the opponent. In effect, instead of using Naturalize or Azalina Soulthief to prevent them from switching back you just murder them the next time they draw a card (which is before they have a chance to interact with the board in any way).

If this catches on, it could be really scary and difficult for many decks to deal with. Some decks can survive against mill druid, but this combo would kill any opponent, at any life/armor total, no matter what secrets they had in play (even if they had an Ice Block in wild).

I don't know is this is viable or just a meme, but imagine putting this in a mill Druid with two Dreampetal Florists or the Twig of the World Tree. Burn through your entire deck and then play King Togwaggle and either a discounted copy of this card or refresh your mana crystals to play this card at full cost. Because the only card in your (now their) deck is the corrupted blood, it will endlessly draw itself and deal 3 damage, instantly killing the opponent. In effect, instead of using Naturalize or Azalina Soulthief to prevent them from switching back you just murder them the next time they draw a card (which is before they have a chance to interact with the board in any way).

If this catches on, it could be really scary and difficult for many decks to deal with. Some decks can survive against mill druid, but this combo would kill any opponent, at any life/armor total, no matter what secrets they had in play (even if they had an Ice Block in wild).

I honestly see this card as pretty meh. If it had stealth, it would be absolutely terrifying in certain decks, but it currently is just so weak to silence, transform, and hard-kill that it just doesn't cut it. Also, if it were to eat a card from your opponent's deck, it would be WAY better with the ability to screw up combos like Shudderwock in much the same way that warlock does.

If hunter gets some strong draw tools this expansion, midrange beast hunter is going to be absolutely brutal. It already is a tier 2 deck, but reliable reload that isn't named Rexxar will really push it to a new level (not to mention that a 3-mana 3/4 with an ability that makes it a priority kill doesn't hurt to play on its own)

I played a Temporus dragon priest way back when down to rank 1 and it was really effective (Potion of Madness, Drakonid Operative, Netherspite Historian, and Dragonfire Potion are all vital for the deck to function), but the current meta just doesn't allow for this gameplan. If you use it against a non-token meta druid, you just die; similarly, most zoolock, paladin, even-shaman, and midrange hunter decks just deal so much damage so early that you can never risk playing your Temporus. 

https://www.hearthpwn.com/decks/1036259-deathrattle-mind-blast-otk-40-120-damage