Cthun the shattered with Raise Dead will be insane, that's the whole idea of this deck.
This is quest warlock that only run Vargoth as a minion, so your Raise Dead will only have these 3 minions in the pool : Vargoth, Body of Cthun, and Cthun the Shattered.
The playstyle of this deck is pretty straightforward:
1. You Clear and Clear your opponent board,
2. You Shuffling and Shuffling to get all that Cthun Spell.
3. You Cast and Cast that Cthun Spell to prepare your Cthun. Draw it with The Dark Portal.
4. You Bam and Bam your opponent with your Cthun.
5. Your opponent not dead yet? You raise dead and Bam Bam again.
The nice things you should notice about the deck is :
1. Vargoth can help you clear a lot with the removal spell (especially the new one, Cascading Disaster), get alot of value from Cthun Spell, and help you complete quest early when played along Plot Twist.
2. If you managed to get 0 mana Twisting Nether or Cthun, you pretty much win the game (unless your opponent has armor or heavy deathrattle).
3. The Cthun Spell help corrupt the Cascading Disaster.
4. You can replay the Cthun up to 4+ times if your raise dead have a good hit, so you dont necessarily wait the C'thun to be the OTK to drop it.
Have fun, cults!