OK, so here's the concept. If you cast
Day's Undoing
with Sphinx's Tutelage on the board, they are going to draw 7, and you are going to get 7 Sphinx's triggers (they happen in the cleanup phase right after the turn is abruptly ended, it's a little weird). That's a guaranteed 21 cards milled out of your opponent's deck. If you assume your opponent is playing 40% land, that's a 36% chance for each of your triggers hit two non-lands. If your opponent was playing a two color deck with half of their cards in each color, there would be 50% * 36% chance that each two non-lands match. In practice this is conservative due to do many decks playing a single base color, and the large number of multicolored cards in standard right now. So you can expect around 2 to 4 extra triggers. A single Day's Undoing plus a few turns of Monastery Siege, or two copies of
Day's Undoing
is more than enough to win.
So what are you doing to survive to find and cast these three mana do-nothing cards? Turbo Fog of course. Fog is a strange card. So long as you cast one every turn, and your opponent has neither burn nor counterspells, it's
Time Walk
. As soon as you miss a single turn, it turns out that all the fogs you were casting were just blank cards all along. What's the best way to never run out of Fog effects? Well, playing a card that reads "Draw 7" for three mana is near the top of the list. Oh, we have one of those legal in standard in our deck already? How convenient.
So that's our deck. We play 12 copies of Fog. The best pure card selection enablers we can find (Monastery Siege, Anticipate). And a do-nothing 0-cost artifact to deal with the pesky graveyard shuffling clause on our marquee card (Tormod's Crypt). This card is probably the worst part of the deck. I have been toying with removing it from the deck for more card draw, which means you can't really chain
Day's Undoing
as a win-con, but just a few turns fogging with Monastery Siege out is about as good as the second copy.
The deck appears surprisingly effective in my tests. Abzan decks are too slow and can do literally nothing to interact with us unless they are running Dromoka's Command. Esper Control has too few win-cons, and they don't know whether to counter the meat of the combo or the enablers (just Monastery Siege + Sphinx's Tutelage is enough to beat them, we run more fogs than they run counterspells and we have great card selection). Fast red decks can be tough depending on how much reach they have. We can win on turn 6 pretty reliably, but we gave them two draw 7's and two untap steps for instant speed burn. GR dragons/devotion might pull off a win if they can cast
Crater's Claws
for some ungodly number, but their creature plan is pretty much invalid and Dragonlord Atarka is basically a blank card.
Let me know what you think!
