Hearthpwn

1-st Update:
i replace Evolve for Unstable Evolution cause it has more flexibility,some times you dont want to hit with evolution some of your minions,in late game it  has a lot of resources in combo with Doppelgangster,also if your hand is empty you rather have Unstable Evolution instead of Evolve.
  -1 copy of Manatide Totem + 1 Ancestral Knowledge,some times you need to draw RIGHT NOW to find some combos,also if your hand is empty you rather topdeck 2 mana spell instead of totem.
If you face a lot of control decks you can put Archivist Elysiana,she will help you to not die from fatigue also,if your deck have no minion that can upgrade your Shudderwock with Divine Shield,Windfury,Taunt,LIfestreal you can replace you deck with Elysiana and find right cards.
Also if you face a lot of aggro decks you can replace Hagatha's Scheme for Lightning Storm
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Let me explain most of combos:
Bog Slosher is  actually  good with ALL minions in deck because most  of them has a  battlecries,by using him you can replay some cheap cards like: Sludge Slurper, Glacial Shard and Echoing Ooze to get more tempo and by playing more battlecry cards improve Shudderwock.
Corpsetaker combine with Zilliax, but if you get unlucky  to draw Zilliax you still has in deck these cards:C'Thun's Chosen ,Al'Akir the Windlord, and one of my favourite new cards big boi Walking Fountain.
1 Evolve need to get tempo with combo: Evolve + Doppelgangster.
And main card our lord Shudderwock,he is a main card in deck. Shudderwock make a great job with  Corpsetaker,then he summon copies of him self using Doppelgangster and Echoing Ooze,then you can get back in your hand Shudderwock when he repeats Bog Slosher's battlecry(next time Shudder will summon buffed copies of him self). To make your board bigger you can play 2 copies of Doppelgangster because usually when you play Shudderwock he summons 2 copies and returns 1/2 of them in your hand, BUT if you play 2 Doppelgangster you summon 4 and return 2,you still has 3 Shudderwocks each of them repeat Echoing Ooze's battlecry so you get fill your board with REALLY good minion who has an taunt,divine shield,windfury,lifesteal.
To make our opponent delete the game i added Loatheb,after Shudderwock fill your board he also complicate board cleaning.
But this deck is not only about fill your board,with every Shudder's battlecry you buff second wincondition : C'Thun,with only 1 Shudderwock your C'Thun became very big,but if you get lucky you can play Shudderwocks many times and kill you opponent with 100/100 C'thun.(I remember how i play Shudder only 2 times and my C'thun became 48/48,just imagine what happen if you play 3-4 times).
Finally i want to say that this is a midrange deck,it  can win by tempo plays without making a BIG COMBOS with Shudder and C'thun(i believe),and also have many resources and opportunities in late game.


That cards i thinking about and why i do not put them into the deck:
I also thinking about Twilight Drake and Star Aligner combo,but dont have dust to try it in game.(you can rebuild deck by your self and try,but i think this combo too slow for midrange deck).
Midnight Drake and Twilight Drake- no space in deck
Fungalmancer- i think he's bad,but you can try.
Barista Lynchen - too slow for deck(imho)
Grumble, Worldshaker - you want to make the board not to make infinite Shudderwock combo,also every shudderwock add some cards in your hand,when you play Grumble-Shudder combo you can lose all you Shudder's because of lack of space in hand,some times he make a good things but honestly i dont have Grumble  card and a cant test him,you can try him(then tell me how good he is).
Hagatha the Witch- she deals damage to your board,and many times i have  no  space in hand to get  cards and  another Shuddewocks .You have a lot recoures to win with out her(remember that you has a lot lifesteal and big board and probably otk C'thun).
Replacements:
Zilliax- scond copy of Walking Fountain
Al'Akir the Windlord- maybe Psych-o-Tron or Omega Defender

Let me know what you think about my deck,i tried to make a fun play deck but strong and playable in ladder.Also this is not too expensive deck,because C'Thun is free,and other legendaries playing in most of decks(Zilliax,Loatheb,Al'Akir,Shudderwock).