Shudderwock is broken in Wild. That's kinda it. Combining 3 cards - Doppelgangster, Grumble, Worldshaker and Shudderwock gives you infinite Shudderwocks for 1 mana, if you won't get screwed by rng - meaning all grumble battlecries will go off before all doppelgangster ones. I used plural form, cause that's actually your priority number one - to get multiple battlecries from your key cards - you grumble cards back to your hand, you copy them with Zola or Banker. You do all kinda shenanigans to improve your chances of going Infinite. Also you can guarantee it, by grumbling Murmuring Elemental or just playing it with a coin before Shudder. 

This deck uses C'Thun kill strategy on top of broken combo - it's not the best and not the worst - I just get really nostalgic about The Old God and like playing him. He feels epic. This is why Omega Defender is in the deck. That makes your shudders have 16 attack instead of 6, so it pings your opponents board and face for a lot more. 

And Reno Jackson on top of that just cause he's our Hero and cool way to piss off aggro decks or midrange decks, that try to stop you before you trigger the combo.