Here's the proof of my ranking here and the decklist here if you just wanna skip the incoming wall of text.

After climbing to Diamond with Bant Midrange, I saw a similar list on Twitter that was being played by Savjz / John Rolf, and then later found another list (whom I can't find the author of on Twitter), and then I modified it slightly to it's current form.

The walkers are the bread and butter of the deck, so we'll cover those first:

Dovin, HoC makes control mirrors awkward and midrange also a bit slower, with the tax and the occasional blanking of bigger threats can make your opponent's math a lot worse, especially paired with Kasmina.

Narset is good. She gets most of the deck. Nuff said, I don't think there is a whole lot to say about her that hasn't already been said.

Lil' Teferi also shuts down control, instant speed stuff, bounces stuff, and in a pinch just bounces Fblthp for extra draws.

Kasmina is surprisingly good, I initially wrote her off but the original iteration ran 2x and the new one runs 3x. Her tax, similar to Dovin's, messes up your opponent's math. Paying 6 CMC for a contempt against Grixis and Esper feels really bad, plus she loots bad draws and makes dudes. Really hard to go wrong unless it's Bant midrange or they play very little removal.

Big Teferi / Ugin mostly handle problem permanents or draw cards, with games 2 & 3 making big Teferi better with Veto.

Sarkhan is definitely the wincon, slapping him down with some walkers on board pretty much seals the deal most games, and demands an answer or they lose. Running 19 walkers usually means you have 2-3 walkers already in play means he threatens 8 damage immediately.

I also played with a Kaya in here for a bit, which was cute vs. Mono R but I wouldn't really force you to play it unless she's super relevant in your meta.

Shocks and Strikes give you removal and reach in early game, deals with walkers (since only Big Tef and Ugin really deal with them without tokens). Spell pierce gives you unexpected counters, get filtered by Kasmina. Clarion makes or breaks WW or Mono R.

4 Fblthp for chumps and 1 Spark Double for random plays, as I said earlier the Double can be swapped with a Kaya if you want, or another walker somewhere. I usually board him out.

Honorary mention to [[Interplanar Beacon]], it shores up the aggro matchups and often nets you 5-15 life in a game with multiples. It for sure makes-or-breaks against Mono-R.

Most matchups are pretty fair, I think Mono R is the worst matchup by far unless you draw multiple Beacons or clarions. Esper is good, I say Grixis is bad but I keep winning against it so I may be wrong. Sultai /Golgari are pretty good if you can deal with Wildgrowth early. Bant is good if you can reliably chump Oketra and wipe the board, but you can easily lose to a good hand. In all my ladder matches in the past ~4 days with different variants of the deck, I have only played a couple games against Weenies, Red, Tokens, and random fringes. I'd like to practice more against them, but Arena is Arena.

Sideboard Guide (cause someone asked for it)

I'll preface this by reminding the reader that your sideboard should be tuned to your local metagame, not some random stranger on the internet. What works for me doesn't always work for you if your local metagame is all RDW, etc.

Esper:

• Fblthp, double, clarion
• Veto, Realm, Spyglass, Manip if you want. (trim sarkhans and Big Tef)

RDW:

• Lil Tef, Big Tef
• Wanderer, Clarion, Lyra, Divine (If they are playing Frenzy)/Prison

Mirror:

• Kasmina, Dovin, Clarion, Double
• Realm, Manip, Veto

Bant Midrange:

• Kasmina, Dovin, Double
• Clarion, Realm, Manip

Grixis:

• 1 Clarion, 4 Fblthp, double, 1 Pierce, 1 Sarkhan, Big Tef
• Veto, Manip, Realm

Also if you guys want to watch all my VODs, you can find them here. I stream pretty frequently.