Eldraine has yet to be released on paper, but Arena is already abuzz with various Standard brews. There are Black-based aggro decks, Fires of Invention decks, and Golos Field at the top end. The lion's share of the metagame, however, goes to Oko decks. There are different midrange permutations of Sultai, Bant, and Simic, but my favorite variant skips all that in favor of a bunch of counterspells:
Oko Flash (20-6 on Bo3 Ladder)
4 Breeding Pool (RNA) 246 4 Temple of Mystery (M20) 255 2 Fabled Passage (ELD) 244 1 Castle Vantress (ELD) 242 8 Island (M20) 268 5 Forest (M20) 280 4 Spectral Sailor (M20) 76 4 Brineborn Cutthroat (M20) 50 1 Wildborn Preserver (ELD) 182 3 Brazen Borrower (ELD) 39 4 Frilled Mystic (RNA) 174 4 Nightpack Ambusher (M20) 185 2 Unsummon (M20) 78 4 Quench (RNA) 48 2 Negate (M20) 69 4 Sinister Sabotage (GRN) 54 4 Oko, Thief of Crowns (ELD) 197 Sideboard: 2 Mystical Dispute (ELD) 58 2 Veil of Summer (M20) 198 3 Aether Gust (M20) 42 3 Lovestruck Beast (ELD) 165 2 Negate (M20) 69 1 Shifting Ceratops (M20) 194 1 Questing Beast (ELD) 171 1 Wildborn Preserver (ELD) 182
Planeswalkers in Flash?!
I've previously described Flash as a mainstay of Standard 2020. Specializing in 100% spells that play on your opponents turn, you bind opponents in a turn-after-turn stasis, countering every threat or presenting one when the opponent failed to do so. What, then is a sorcery-speed three-drop doing in this archetype?
Well, Oko is simply broko. Why hold up counterspell when there's no stronger three-drop in the entire format? He does it all - make 3/3s, gain life, neuter threats, and steal creatures - without costing any mana after the initial investment. With an Oko resolved, you win the board by default, and the impetus is on your opponent to present a sufficient answer -- not easy when the rest of your deck is counterspells. His power and flexibility mean that the category of cards that you lose to (and thus need to counter) shrinks dramatically.
Here's a game I played against Br aggro:
T2: Flash in Brineborn Cutthroat to trade with Dreadhorde Butcher
T3: Oko, make a food
T4: Turn it into a 3/3 to hold off Robber of the Rich
T5: Trade in 3/3 against Blacklance Paragon, make another food.
T6: Steal their Rankle, they concede
Aggro is traditionally one of the deck's weaker matchups; answering 1- and 2-drops with 2- and 3-mana counterspells is a horrible tempo play. Over a couple activations, Oko gained me back all that mana inefficiency. A conservative estimate might set a 3/3 to be worth 2 mana, stealing their 4-drop to be worth 5, and 2 mana for an extra card draw; that's 9 mana of value, and my Oko is still on board!
The other main gain from Eldraine is Brazen Borrower. Flash is a tempo deck, not a control deck; the important thing isn't to counter every last one of your opponent's cards, but to prevent their cards from mattering while you kill them. When your opponent is dying with a grip full of cards, Disperse is indistinguishable from Vindicate -- and Brazen Borrower is a Disperse that draws you a flying 3/1 beatstick. It's also very strong with Oko -- turn 2 bounce their guy, turn 3 uncontested Oko will win a lot of games.
Never Upon A Time
You may have noticed a lack of Once Upon A Times and Opts in this list. A lot of other Flash lists play those in place of Okos and a couple lands. My reasoning is that many of your cards are actually interchangeable, so the card selection is less important. Once Upon A Time is strong because it:
1. Fixes your mana
2. Finds your early creatures or late-game threats, and
3. In Magical Christmasland, does it all for free.
Well, in Simic Flash:
1. Mana fixing is less relevant in a two-color deck (yes, Frilled Mystic is still sometimes a pain)
2. Your creatures all play the same role (end-of-turn threat that beats your opponent to death)
3. Most importantly, mana is pretty tight in the crucial first 4 turns, and even afterwards as the deck has no ramp and few sources of card draw. I'm not interested in paying a 2-mana premium to have any of the creatures in my deck, when I already have mana sinks like Spectral Sailor, Wildborn Preserver, even Brazen Borrower.
In short, consistency isn't something Flash struggles with, but the extra mana cost is absolutely a factor that can sink a game.
I think Flash actually gains a lot in postboard games. Your maindeck is full of cards like Quench, Sinister Sabotage, and Frilled Mystic -- counterspells that hit any spell color and type, to reduce your dead draws in game one. After boarding, though, you get to play conditional counterspells like Aether Gust, Veil of Summer, and Mystical Dispute. These do the same job of answering their spells, at a much more efficient mana cost.
A major consideration when crafting your sideboard plan is whether you are on the play or draw. On the draw, Quench is much better as it trades up on mana against their 3-drop; plus, as they start "down" a card, they are less likely to have the lands to pay the tax. Meanwhile, Oko is much stronger on the play turn 3; I would shave some copies on the draw, especially if it looks like you need to counter their 4-drop (any midrange deck or slower).
The classic hate cards people side in against you are Teferi and Shifting Ceratops; both are beatable but involve some planning. Teferi can be stopped a variety of counterspells, bounced via Brazen Borrower, or killed with Questing Beast or Shifting Ceratops. Opposing Ceratops can be blocked by your own, Lovestruck and Questing Beasts, and Wolf tokens (Nightpack Ambusher itself is inadvisable but sometimes necessary), or delayed on the stack with Aether Gust.
Your biggest headache, though, might be Knight of the Ebon Legion from Black-based aggro decks. That card is ridiculously difficult to answer with any kind of tempo, and grows to beat all your creatures in combat. I'm still looking for a good solution here -- Lovestruck Beast is my current attempt.
Vs Oko Midrange (Sultai, Bant, Simic)
You're usually the beatdown, as their top end of Hydroid Krasis outclasses everything you can do. The good thing is that their deck is full of mana sources, so their threat density is rather light.
+3 Aether Gust, +2 Mystical Dispute, +1 Wildborn Preserver, (+2 Veil if Sultai) -2 Quench, -1 Unsummon, -2 Negate, -1 Sabotage, (-2 Oko)
Also bring in Ceratops and Questing Beast if you're struggling against their Ceratops.
Oko absolutely shines here, giving you Elks or feeding you a healthy buffer of life.
+3 Aether Gust, +3 Lovestruck Beast, +1 Questing Beast -2 Frilled Mystic, -3 Sinister Sabotage, -2 Negate
Vs Bx Aggro
Hard matchup, since all their creatures are cheaper than your counterspells but also real threats.
+2 Veil, +3 Lovestruck Beast, +1 Questing Beast, (+2 Aether Gust if Red) -2 Negate, -3 Sabotage, -1 Frilled Mystic, (-1 Unsummon -1 Mystic)
Vs Jeskai Fires
Should be a bye (as I demonstrated vs Bloody on stream). Their game plan revolves around a 4-mana enchantment, which is pretty soft to your game plan of counter everything relevant.
+3 Aether Gust, +2 Mystic Dispute, (+1 Questing Beast, +2 Negate if Superfriends) -3 Quench, -1 Oko, -1 Sabotage, (-2 Unsummon, -1 Sabotage)
Vs Esper Stax
Also an easy matchup. I love playing against decks where Negate is straight-up Counterspell.
+2 Negate, +2 Mystical Dispute, +2 Veil -2 Unsummon, -2 Quench, -1 Oko, -1 Wildborn Preserver
Vs Golos Field
This has been my worst matchup. They have Teferi, Krasis, Golos, and Field, all of which we struggle to beat. I think we play all our creatures and switch to a beatdown deck, instead of trying to counter their ramp.
+1 Questing Beast, +1 Ceratops, +3 Lovestruck Beast, +1 Wildborn Preserver -2 Unsummon, -3 Quench, -1 Sabotage
Vs Flash (mirror)
Haven't faced it on ladder yet, but I think just bring in all your hate cards and see what happens.
+2 Veil, +3 Aether Gust, +2 Mystic Dispute, +1 Ceratops, +1 Wildborn Preserver -3 Quench, -2 Frilled Mystic, -2 Sabotage, -2 Unsummon
If you enjoy a deck that plays uniquely, rewards format understanding, and has a bit of a rogue factor, I'd encourage you to take Oko Flash for a spin. I'll be piloting this list at SCG Philly this weekend, and would love to hear your thoughts and feedback!