Competicasual Kozilek EDH.

This deck functions like a Rube Goldberg machine. In other words it performs a very simple task in the most complicated way possible. If you don't like complexity this deck is NOT for you.

There are a few off the wall combos in this deck but I'll point out just a few. Most of the combos in this deck work with other combos in unintended ways to make a complex network of weirdness.

Paradox Engine + Spine of Ish Sah + 7 mana from mana rocks. (Sounds like a lot but actually isn't.) This base combo is my main go-to lately since it's so easy to pull off and fairly resistant to removal, it works by tapping the Rocks for 7 to cast Spine of Ish Sah and then the Paradox Engine trigger untaps your mana rocks. What happens next is Spine of Ish Sah's trigger will target itself and blow itself up. When it gets blown up it returns to your hand. This results in infinite untaps of all artifacts on the battlefield. Add Sculpting Steel to reduce the cost to 3 required mana, add krark clan ironworks to reduce the cost by 2 and the ability to destroy all permanents, add Semblance Anvil imprinting an artifact to reduce the cost by 2, add Staff of Nin/Endbringer for infinite damage, add 1 more mana from mana rocks and you get infinite mana. At this point you can start to see how this deck can be quite complex and exactly why I call it a Rube Goldberg machine.

Other combos of note include Basalt Monolith + Rings of Brighthearth for infinite mana but adding in a Voltaic Key lets you also have infinite artifact untaps which can be paired with Staff of Nin for infinite damage or a host of other options for various effects.

Any infinite mana combo makes Staff of Domination draw our library.

If you are using krark clan ironworks +Spine of Ish Sah + Paradox Engine/Rings of Brighthearth + Basalt Monolith you not only get to destroy all opponents' permanents but you get infinite draw as well since you can continually target your kozilek butcher of truth with Spine of Ish Sah and recast him. The previous combo can also be accomplished with krark clan ironworks + Spine of Ish Sah + Sculpting Steel + Semblance Anvil. This can be useful if someone has indestructible permanents from something like Darksteel Forge + Mycosynth Lattice (looking at you daretti scrap savant) or if their board has hexproof for some reason. At this point you can draw into a Staff of Nin or an Endbringer to kill them directly.

I do run a fair bit of Stax elements just to keep our opponents slowed down a bit while we power out things using mana rocks. Having a Winter Orb isn't a problem when you have 5 or 6 mana rocks that can cast your entire deck.

Faq:

Q: Why Kozilek butcher of truth over kozilek the great distortion? 
A: Kozilek butcher of truth Draws 4 cards, kozilek the great distortion refills to 7, meaning I can never have more than 7, not very useful if I plan on killing/casting Kozilek multiple times in a turn to draw cards. Plus Annihilator is a thing. It's a very nasty thing. Especially when turn 3 Kozileks are a possibility. That ability alone can prevent someone else from interacting with you for the rest of the game.

Q: Ok, so why not ulamog the ceaseless hunger or ulamog the infinite gyre?  
A: They don't draw cards. Yes they are removal from the command zone but they can't refill my hand after I chain out mana rocks required to cast either Ulamog which leads to an empty handed ohthenoises and a bad time. Empty handed with a 10/10, indestructible or no, is a recipe for losing the game to being targeted.