Hearthpwn

So the basic idea of this deck is two-fold.
-Building around Renounce Darkness
-A core C'Thun win condition

Early game should be dominated by your warlock cards. As far as early game goes Warlock has some of the strongest starts between Flame Imp, Voidwalker, and now Forbidden Ritual. On top of that all of the neutral C'Thun cards are very respectable in value by themselves and should make for a very smooth early dominance.

The times where that doesn't happen is where some of the more unusual cards come in. DarkBargain, Fist of Jarraxus and Deathwing are all there for more defensive plays. The meta right now is slowly and steadily moving to big if not huge drops during the late game, so unconditional removal like Dark Bargain should be seeing more great use cases.

Improvement

I'll completely admit this is a rough deck in need of several tweaks before it's competitive in any form.

Right now I'm going to explore how well Renounce Darkness will function as a mid/late game fallback for converting the early game warlock cards. Depending on the consistency of well...completely random.... generation I'll need to adjust the ratio of the class cards versus the neutral cards in this deck.

I'm also experimenting with Usher of Souls. It's a little to late game of a class card for me to be comfortable including with Renounce Darkness, but at the same time the combo with it and Forbidden Ritual is a bit too strong to just dismiss in a warlock C'thun deck.