Took some of the ideas from my Opus/Rites deck and repurposed them into an Ultimatum deck. The plan is as many huge turn 4s as possible, ideally winning by casting Emergent Ultimatum multiple times and taking extra turns with Alrund's Epiphany.
Emergent Ultimatum is pretty obvious, our goal is to cast this turn 4 and profit.
Unburial Rites helps up do that, by reviving Scholar of the Lost Trove. Indomitable Creativity combines with token producers, and always hits any remaining Scholar of the Lost Trove left in the deck. This is better than Mizzix's Mastery for a couple of reasons, though it is matchup dependant. Mizzix's Mastery still makes the cut, as having 10 ways to flash back Ultimatum is incredibly useful, overloading it occasionally comes up, and because it is also a card you can cast with Ultimatum piles that you want a couple of copies of for those purposes, largely because we can't run Glasspool Mimic
and Creativity. That seems like enough ways to cast your stuff.
You need ways to pitch stuff into the GY. Faithless Looting is the best red way to do this, Thrilling Discovery helps mitigate life loss from shocks while furthering your game plan, and Prismari Command also produces mana/fixing/a token for creativity. 12 seems like a fine package, and your nuts plays where you curve out with a 1, 2, and 3 drops almost always result in stack graveyards. Even hitting just 1 or 2 of these helps set up the t4.
Omniscience, Final Parting, Sublime Epiphany are all run as 1 ofs for the purposes of Ultimatum piles. Alrund's Epiphany is a 3 of, because this decks actual "win" condition most of the time is swinging in with flyers on extra turns, and you need a few of these for the purposes of putting together Ultimatum piles. With 1 in the Hand or Gy and at least 1 in the deck you can guarantee and extra turn, no Time Warp nessessary.
Magma Opus still makes the cut in Creativity based versions of the deck, for a few reasons. It is good with Omniscience, it produces a token for Creativity, and lastly it makes a solid back-up plan for games where you don't see Emergent Ultimatum, as against the matchups your deck is good against it is almost as good anyways.
Basic plan is to hope to dodge counterspell based Control or Tempo decks and then just win on the spot in an early turn of the game.
