This is the closest you can get to a viable mill deck in standard. Shockingly, this deck has been slaughtering people when I thought mill was completely dead. I've won like 10/14 games with this deck at like rank 8, which is really high for me because I make all of my own decks and change decks quite often and don't seriously ladder.
You probably know the drill by now, in control matchups, you want to trick them into drawing cards, then when they have like 7 or 8 in hand, you nuke him with Coldlight Oracles and Naturalizes and they end up losing like 3 or 4 cards. In aggro matchups, you care less about milling their cards, but there's a ton of survivability in this deck. Your win condition is stabalizing and getting board control and eventually getting too much health. This deck is a free win vs most mage decks because when you have board control, you can easily remove every card they play and your armor becomes too big for them to fireball you down. It struggles a bit against zoo warlock and deathrattle hunter, but they're nowhere near as popular as C'Thun decks right now.
Interesting things about the deck are the inclusions of Raven idols, and Fandral Staghelm. I never realized how good it is getting another removal spell or another Naturalize from raven idol, and if you do the combo, you get a minion as well. Nat, the Darkfisher is a total MVP too. Vs aggro, he often secures board control early on as he can kill almost anything they play and live until turn 4. And vs control, they don't usually have an efficient way to do 4 damage to a minion from an empty board, so he usually ends up surviving and drawing them at least 2 cards. If he draws them 1 single card, it's already really good.
Some cards to consider putting in: Jungle Moonkin/ Wild Pyromancer for better board clear turns, and maybe Sen'jin Shieldmasta is better than Cycloptian Horror. And maybe Earthen Ring Farseers/Refreshment Vendors
All in all, this is my favorite deck in the expansion so far, and it's been doing well. There's just something special about overdrawing them C'Thun that brings a tear to your eye. :')