This change was mostly motivated by the fact that Aetherworks Marvel was banned, whether you believe it should have been or not is a separate issue.
The changes were as follows:
Mainboard
-4 Void Winnower, +4 Emrakul the Promised End
-1 Aether Meltdown, +1 Ugin the Spirit Dragon
Sideboard
-2 Appetite for the Unnatural, +2 Natural State
-2 Sphinx of the Final Word, +2 Nissa's Renewal
-2 Metalic Rebuke, +1 Ugin the Spirit Dragon, +1 Dragonlord Atarka
The change to the main board is simple enough, restore the creature base to how it was in its original incarnation, because Emrakul is Emrakul. Most of the time the cheapest she will be is eight mana, so I will be relying on Aetherworks Marvel to cast her and Ulamog. Ugin was added as a one of mainboard to serve as a bit of a surprise, bolting or board clearing out of nowhere is rather fun. While I could include more in the main, I decided to stick the second in the side so as to leave another slot open for cheaper cards to go into the grave to make Emrakul cheaper. The arrangement has so far worked, with Ugin proving to be the turning point more then I expected.
The side is untested so far, with this serving as the current idea for what I want to turn it into, moving it away from the control match up sideboard to a more versatile, with the Nissa's Renewal servicing as a ramp option that I can select from an Aetherworks hit in matches where I may only get one chance to use it. I changed the Appetite for the Unnatural with the cheaper Natural State, keeping Release the Gremlins to deal with the more expensive artifacts I may encounter. And finally, I added the second Ugin and a Dragonlord Atarka to have some other options for Aetherworks or cheaper cards to cast if I miss.