creature snowhorn tron first draft

Decklist: https://i.imgur.com/Xhdr9Z3.png

Matchups Guide:
Just going to go in order of the MTGGoldfish meta share, which is effectively just a random order, with the lesser variations of each archetype behind the main one.
Big players
Jeskai (all flavors)
There are a huge amount of variation in card choices, but they're all basically the same - 4 Astrolabe, 4 Counterspell, some numbers of Mulldrifter/Archaeomancer/Ephemerate/Skred, and then some more creatures and spells. Here's what you need to look for - do they play Spellstutter Sprites? Do they play Seeker of the Way? Do they play Augur of Bolas? Do they play Glint Hawk, and do they have Prophetic Prism to support it or Trinket Mages to find Astrolabe? How many Kor Skyfishers do you see? Do they have Lightning Bolt?
Sideboarding is rough for this matchup - you need some numbers of everything for some versions, and other versions you can vastly shift your deck and get a huge advantage, and you only get a game or two to figure out what they're on. Giving a direct sideboarding guide would be worthless given the realities of the matchup against different builds, so here's the cards that you can put in and take out, and what they're good against:
Out:
Condescend - Extremely awkward to counter 1 mana spells with Condescend and get countered by 1 mana spells. If they have something strange like Palace Sentinels then maybe you'll want it, but it's usually the first card out no matter the opposing build.
Stonehorn Dignitary - Necessary against Glint Hawk, still good against Seeker of the Way even without Glint Hawk, and can be cut against Augur builds.  If you cut the Stonehorns you can cut the Plains too.
Moment's Peace - Necessary against Glint Hawk + Seeker builds, otherwise easily cut. Against Kor Skyfisher + Sprite builds, I like 1 Moment's Peace to Teachings for plus 1 or 2 Stonehorns.
Pulse of Murasa - Very good, though vulnerable against Relic. If you see more than 1 Relic in an aggressive build, cut it to avoid a nonfunctional draw.
Dinrova Horror - One makes winning through Kor Skyfisher tremendously easier. Having both allows you to expose one to a Relic, or expose your Compulsive to a Relic, while still having inevitability. If you have both, you can also just jam Horror to bounce an opposing land and have a juicy Flicker target lying around. If you have 1 Horror, the Compulsive, the Pulse of Murasa and the Shattering Pulse, you're generally going to be able to win the game no matter how unfortunate the sequence of cards you draw is, but as you start cutting more of those out of the equation it just takes an unfortunate few turns where you have to just jam your Compulsive on turn 3, it gets eaten by a Relic at some point, and then your Horror is the actual bottom card for you to be unable to kill the opponent through a Kor Skyfisher or two. Often though you can race the opponent by swinging in your creatures and Flickering whichever creature gets blocked by Skyfisher, though again sometimes you just have the Horror as the bottom card and 4 more 2/2s are in the bottom 7 cards and you just can't get enough damage through, and having two Horrors makes that significantly less likely though still possible.
Ghostly Flicker - extremely good in this matchup since it can just Divination at the end of their turn and be a great card, but sometimes you just need to make room and the sixth Flicker effect ain't necessary. More Flickers means graveyard hate does less and less, though.
In:
Pyroblast - you need at least 2 against all the different builds to fight Counterspell/Archaeomancer/Mulldrifter. Against the Augur + Sprite versions, you can jam all 4 safely. Against Glint Hawk + Seeker builds, if you draw too many Pyroblasts you can just get overrun.
Blue blasts - a necessary evil against some opposing sideboard cards, and 2-3 are good additions against Augur builds, since you can stack up all your counters and match your Blue Blasts/Dispel/Prohibit against their Pyros and your Pyros/Gut Shot against their Sprites.
Gut Shot - awesome against Spellstutter Sprite and can lead to massive blowout potential, and frees up your Pyroblasts for other uses.
Stonehorn Dignitary - very good against the 4x Seeker builds, necessary against Glint Hawk + Seeker builds. I generally never bring in all seven anti-combat cards, and Stonehorn is much better than Moment's Peace as it gives you a Flicker target.
Shattering Pulse - can be insane against Glint Hawk versions, as if you blow up the Astrolabe they mulliganed/cantripped for you can strand a huge number of cards in their hand. Adequate against Trinket Mage builds to snipe Relics after tapping them out, or forcing them to pop. Late game, just blowing up all the opposing Astrolabes to choke their red and white mana and strand their birds in hand. Generally, bring it in if you see artifact lands or Glint Hawks, though if they don't have artifact lands and do have Prism then it can be a pretty huge waste of mana that doesn't do much. If they have 2+ Relics then bring this in to make winning easier, though Horror also does a good job at making a mockery of Relic.
Tron (all flavors)
The mirror match is horrendous. Here's the deal - if one player hits Tron and the other player misses, the player with Tron wins. If both players hit Tron, but one player misses on colored mana, the player with colored mana wins. If both players hit Tron and colored mana, but one player floods and the other player draws relevant spells, the player with spells wins. If everyone draws Tron and colored mana and relevant spells, the player on the play wins. It sucks. Even if you build your deck to target the mirror, and play against someone with a pile of useless anti-combat cards in the maindeck, you're still not going to be better than like 60%, because often the poorly positioned version is just gonna out-Tron, or out-Prism, or out-draw you, or just happen to win the die roll. Anyway, game 1 just setup a Horror loop and keep an eye on what they play to see what you wanna board.
Flicker Tron (the Mirror)
Sideboarding -
Out:
3 Stonehorn Dignitary
2 Moment's Peace
1 Plains
1 Condescend
In:
4 Pyroblast
2-3 Blue Blasts
1 Shattering Pulse
Depending on if you think they're running Rolling Thunder, you can add the third Blue Blast by cutting Pulse of Murasa or Shattering Pulse. Draw better than your opponent, don't tap out and lose the counter fight on your turn and allow them to own you on their turn, etc. Shattering Pulse on Expedition Map while they're tapped down is the dream, but using it to limit their colored mana, or using it late game at the end of their turn with buyback to destroy all their colored mana is good enough, though try not to get owned by Flicker. If they're bringing in Ulamog's Crusher you can keep a Stonehorn or two in, though if your opponent plays Crusher and you play Horror you're insanely ahead so it's not entirely necessary. Crusher really only matters if they just have turn 4 Tron plus land plus Crusher, and also draw a bunch of counters and other good spells to back it up - its effectiveness drops off severely past turn 6 or so as you have a bunch of garbage to sacrifice and can more easily churn through the deck to find a Horror/Stonehorn. Usually Crusher is worse for the opponent than just another counter like Dispel or a 5th Red Blast would be.
Fangren Tron
Sideboarding -
Out:
2 Moment's Peace
1 Condescend
1 Plains
1 Dispel
1 Pulse of Murasa if you need another cut, then 1 Ghostly Flicker
In:
3 Blue Blasts, more if given a reason
1 Pyroblast
1 Shattering Pulse
We're keeping in three Stonehorns because the opponent is running a bunch of dorks so locking down combat is pretty good, and we have two Horrors which double as anti-combat cards so we don't need to bring in the fourth Stonehorn unless we see something odd. Shattering Pulse can just pop a Sphere to deny them a card, or hit Prism to deny them colored mana if they blank on Cave of Temptation, or snipe a Map, or just machine gun down Self-Assemblers if that's their pressure. A Pyroblast is a tutorable way to lock the game up by countering their Mulldrifter and/or Wall. 3 Blue Blasts are for opposing Pyroblasts and also Rolling Thunder - if you see a LOT of red cards, like 4 Pyroblasts plus Rolling Thunder plus some sort of red LD, go ahead and add four or five Blue Blasts, though note that Flicker is pretty great against LD and Pulse of Murasa can make Rolling Thunder pointless.
Snow White Tron
Sideboarding -
Out:
1 Condescend
1 Pulse of Murasa
2 Ghostly Flicker
1 Plains
1 Moment's Peace
In:
3-5 Blue Blasts
1-3 Red Blasts
1 Stonehorn Dignitary
This is the only matchup where I wish I still ran a Circle of Protection: Red, since that allowed you to just straight lock the game up by negating all their fireballs while you lock down combat. We're cutting the Plains even though we have four Dignitaries because we cannot win without a mana-filtering artifact, and we're not forced to play turn 4 Stonehorn or die like we would against an aggro deck, we're just using Stonehorn to lock combat and make their fliers much weaker. I like keeping a Moment's Peace in as a tutorable way to stop combat for a couple turns in case all four Stonehorns and both Horrors are in the bottom 30 cards, but you can't have too many anti-combat cards or you'll just die to a pile of fireballs. Shattering Pulse can be okay, but more Blasts or anti-combat cards are usually better, though if they're jamming a million Relics then you'll probably want it over the last Moment's Peace. Pyroblast pretty much only hits Mulldrifter maindeck, but it also hits Dispel after board - if you see a bunch of Blue Blasts (because the opponent has to take out a ton of dead cards) then you might be able to get away with zero or one Pyroblast to try to strand the Blue Blasts in their hand.
Affinity
Atog + Fling is how you lose, other than drawing 20 cards and missing on all the anti-combat cards. If you can lock combat down, you need to churn through your deck to find a Dispel or Prohibit to beat Fling, or start Horroring their board away.
Sideboarding -
Out:
1 Condescend
1 Dispel
1 Prohibit
1 Pulse of Murasa
1 Mulldrifter
1 Ghostly Flicker
2 Dinrova Horror
In:
5 Blue Blasts
1 Shattering Pulse
1 Stonehorn Dignitary
1 Moment's Peace
Post board you seek to prevent them from having access to Atog, or allowing them to have Atog and just holding up multiple ways to counter Fling, while keeping yourself from dying by playing a bunch of anti-combat cards. Eventually you'll clear any Atogs they have, and then Shattering Pulse their entire board and beat them to death with a Mulldrifter or deck them with Compulsive.

Atog Combo
It's Affinity with very few threats and instead tries to use permission to guard what threats they draw. Game 1 you've got to find a Horror and start bouncing their board, otherwise they'll be able to accumulate a hand full of counters and eventually force through lethal in some way, and locking down combat is nice for keeping your life total high but they'll eventually find Atog + Fling + a pile of artifacts and/or Galvanic Blasts. Game 1 frequently comes down to how many Thoughtcasts the opponent can find, or whether they can draw and play the turn 2 or 3 Atog to pressure you.
Sideboarding -
Out:
3 Stonehorn Dignitary
2 Moment's Peace
1 Condescend
1 Ghostly Flicker
1 Plains
2 Dinrova Horror
In:
9 Blasts
1 Shattering Pulse
You are now a traditional control Tron deck. Your plan is to kill every creature the opponent runs. Your removal doubles as counters for their protection. Hydroblast their Atogs, Pyroblast their Serpents, and eventually Shattering Pulse their manabase and board. Some versions run Carapace Forger as an additional threat - if you see those, you may need to keep the Horrors in or maybe some Dignitaries, though you can also just block and Flicker to wall it, or just jam two 2/2s in front of it. Draw as many cards as you can, because they'll be trying to do the same, and you need as many Blasts and counters as you can get. Eventually you'll need to use Walls to get back more Blasts and allow you to convert Flickers into more Blasts. They'll probably still have Galvanic Blast in, as well as Pyroblast, so you're going to have to use counters to defend your Walls, which requires quite a lot of finesse so that you are able to defend your plays while also not dying to Atog + Fling + maybe a hidden number of Galvanic Blasts to the face.
Stompy
Great matchup, and one of the reasons to run so many anti-combat cards. Sometimes you'll have two Stonehorns and no Peace and will die before casting them because you lost the die roll and didn't have the god draw, but if you win the die roll and are able to find an anti-combat card, you are extremely ahead. All your interaction can also put them back a turn or even two from killing you depending on their draw, which means even if you stumble you can still lock them out. Your best draws will beat their best draws, even on the draw, and their best draws don't even beat your mediocre draws when you're on the play, so this matchup can depend on the die roll, but mostly it's when you've got an awkward start and they have a great one.
Sideboarding -
Out:
2 Dinrova Horror
1 Dispel
1 Pulse of Murasa
1 Ghostly Flicker
1 Condescend on the draw
In:
1 Moment's Peace
1 Stonehorn Dignitary
1 Gut Shot
1 Shattering Pulse
Lone Missionary, 1 on the play, 2 on the draw
Neither Horror is necessary, the Dispel is awkward and weak, the Condescend is quite bad on the draw, Pulse of Murasa is awkward and bad against Relic of Progenitus, and you don't need all the Flickers. Moment's Peace, Stonehorn Dignitary and Shattering Pulse are auto-includes, the two anti-combat cards help you lock them down and keep your life total high, and Pulse is your out to Viridian Longbow. Gut Shot goes in because it's great against all their turn 1 plays except Nettle Sentinel and also snipes River Boas on turn 2. Lone Missionary is pretty good at buying time, both against their beatdowns and against Longbow, since gaining 4 life once you've locked down combat can buy you some turns to find the Shattering Pulse or Teachings to answer their Longbow. Shattering Pulse also answers their Vault Skirges, allowing you to beat them to death with Mulldrifters and not requiring you to Compulsive them out, though some crazy people have brought in Hidden Spider which will require you to deck them or loop Gut Shot to either burn the Spider if you can somehow cast it and Flicker loop it four extra times, or just burn them out, so Horror is not necessary to win. Lately I've been bringing in both Lone Missionaries on the draw, and swapping one out for Condescend on the play since Condescend on turn 2 is a huge swing.
Note here my philosophy against aggro decks - if you have dead cards in your hand against Aggro, who cares? It isn't like you're going to lose when they out card advantage you, you'll lose because you don't draw the right cards to lock them out, and it isn't like we're leaving more Peaces or Stonehorns in the board in place of the potentially dead Gut Shot or Condescend - having the ability to draw those cards early and slowing the opponent down a tremendous amount will win you far more games than having a mediocre Dispel or Horror will, even at the cost of those cards sometimes rotting in your hand later.

Elves
It's Stompy with turn 3 wins, more turn 4 wins, and actual reach! Establishing a combat lock is the goal, but that's not the end against some builds game 1, and no builds post-board. Cards to watch out for game 1 - Viridian Longbow is the big one, and related to that are Island, Sylvan Ranger, and Distant Melody. If the opponent is mono-Green, fueled by just Winding Way and Lead the Stampede, then they may have a Longbow or two in the main, but even if they have a busted Priest draw, they still have to draw the Longbow naturally, or they're cold to a combat lock, and they don't get many turns before you can find a Prohibit/Teachings/Horror and Longbow stops being an out. If they play Distant Melody, though, they can easily draw their entire library and find even a 1-of Longbow to win through a combat lock. Some builds are running Melody alongside some numbers of both Winding Way and Lead the Stampede, and you need to be on the lookout for evidence that they run the Island, because it also effects the lines you should take, since you need to much more aggressively pursue a line that allows you to find Horror or Prohibit before they can chain Melodies and kill you.
Sideboarding
Out:
1 Dispel
1 Pulse of Murasa
1 Ghostly Flicker
1 Condescend on the draw
1 Dinrova Horror on the play

In:
1 Stonehorn Dignitary
1 Moment's Peace
1 Gut Shot
1 Shattering Pulse
I tend to Gut Shot their turn 1 mana elf, though I'll leave Birchlore Ranger alive until I see what they want to play next and I'll ignore Quirion Ranger. The dream is to Gut Shot a Priest of Titania, but if they go turn 1 Llanowar and you choose not to Gut Shot it, and they play a turn 2 Timberwatch, you kind of got owned. Even if they just jam a turn 2 Lead the Stampede, it's a huge disadvantage for you, so I tend to just Gut Shot immediately. Shattering Pulse is in to answer Longbow, and that combined with the additional anti-combat cards allows you a lot more leeway. Dinrova Horror is an answer to Longbow and also a way to lock out the opponent once you have a Flicker loop going, but it's pretty dorky and I'd rather have Condescend to try to spike an early successful Condescend on the play. If the opponent is playing Mob Justice, you probably want a Hydroblast; if they're playing Harsh Sustenance, you'll probably want to keep the Dispel; and if they're playing Distant Melody you might want a Pyroblast or two. Cut Horrors or Condescend to fit those in, maybe a Mulldrifter.
Bogles
Bogles is more likely to lose to itself than anything else, though locking down Combat and finding a Dispel to counter Fling is usually enough. Flicker looping Dinrova bouncing their lands and binning their enchantments will also do it. If the opponent blanks on Ethereal Armor or Ancestral Mask then you have plenty of time, and if they hit Armor/Mask but miss on Rancor or Armadillo Cloak then you get to chump for a while.
Sideboarding -
Out:
1 Pulse of Murasa
1 Condescend
1 Ghostly Flicker
1 Dinrova Horror
In:
1 Stonehorn Dignitary
1 Moment's Peace
2 Blue Blast
Dispel hits Fling plus opposing Dispels. If they opponent has other red cards that you want to counter, then cut the other Horror for a third Blue Blast.
Burn
Burn does not have any good matchups anymore, but that doesn't stop people from playing it. It used to be nearly a throwaway for the old version of Stonehorn Tron, but thanks to Astrolabe and a pile of Flickers you aren't nearly as disadvantaged. If the opponent has a turn 2 Thermo-Alchemist on the play then you pretty much need the nuts to have a shot, but if they miss on Alchemist then you can just find a Teachings or a Pulse and shut them out by looping Pulse with Wall and Flickers.
Sideboarding -
Out:
2 Dinrova Horror
3 Stonehorn
2 Moment's Peace
In:
5 Blue Blasts
2 Lone Missionaries
Blue Blasts allow you to answer their repeatable damage sources, and Lone Missionary is a must kill for them else all your Flickers become insane. Beyond those cards, you still have the Pulse and maindeck counters to stave them off, and the Teachings are incredible once they can find Blasts. You have to watch out for Molten Rain and Smash to Smithereens, but they also have to watch out for your Flickers, but you also have Missionaries and Pulse so it's not like they can just sit around and wait for an opportunity to avoid getting owned by Flicker, and having their 3 mana sorcery countered by a 1 mana instant can lead to them getting effectively locked out when you untap and gain a ton of life. Remember how Burn decks work - if your Burn opponent Bolts you 6 times and brings you to 2, and then they lose the game, they discarded 6 cards and did nothing. All you have to do is use your resources to scrap as much life for yourself as you can and then beat the opponent to death with 2/2s or lock them out with Flicker loops to get a hand full of Blasts or gain 40+ life, if you win the game then it didn't matter how much your opponent did to you, as long as you never drop below 1 life.
Small scale
Boros Stuff - Aggro, Monarch, Mardu
If they're playing a pile of artifact lands, Astrolabes, white creatures and trying to burn you out, they're running Boros Stuff. Some decks are super aggro with Court Homunculus, some are traditional Boros Monarch, and some are playing Hawk/Skyfisher/Seeker as their only creatures and trying to murder you with Blightning supplementing the usual burn. Against all of these, your plan is to use anti-combat cards as virtual lifegain, and then find a way to gain a pile of life with Pulse or lock them out with Horror before they draw 12-20 points of burn.
Sideboarding -
Aggro version:
Out:
1 Dispel
1 Condescend
2 Dinrova Horror
1 Ghostly Flicker
In:
1 Stonehorn Dignitary
1 Moment's Peace
1 Shattering Pulse
2 Blue Blast
Monarch:
Out:
1 Dispel
1 Condescend
1 Dinrova Horror
1 Ghostly Flicker
In:
1 Stonehorn Dignitary
2 Blue Blast
1 Shattering Pulse
Mardu:
Out:
1 Moment's Peace
1 Dispel
1 Condescend
1 Prohibit
1 Dinrova Horror
1 Ghostly Flicker
In:
1 Stonehorn Dignitary
1 Shattering Pulse
4 Blue Blasts
WB Pestilence
Sideboarding -
Against creature version:
Out:
1 Dispel
In:
1 Stonehorn Dignitary
Against (nearly) creatureless version:
Out:
2 Moment's Peace
In:
1 Shattering Pulse
1 Lone Missionary
Heroic
Sideboarding -
Out:
1 Pulse of Murasa
1 Dispel
[1 Condescend on the Draw
1 Ghostly Flicker on the play
In:
1 Stonehorn Dignitary
1 Moment's Peace
1 Shattering Pulse if you suspect or see targets such as Relic (boarding out the [bracketed] card)

White Weenie
Sideboarding -
Out:
1 Pulse of Murasa
1 Dispel
In:
1 Stonehorn Dignitary
1 Moment's Peace

Delver (U or UR)
Sideboarding -
Out:
2 Moment's Peace
1 Condescend
2 Dinrova Horror
1 Ghostly Flicker on the draw against Mono-Blue
In:
4 Pyroblast
1 Gut Shot
1 Lone Missionary on the draw against Mono-Blue
Slivers
Sideboarding -
Out:
1 Pulse of Murasa
1 Dispel (keep in if you see Swamp or Harsh Sustenance in place of a Ghostly Flicker)

In:
1 Stonehorn Dignitary
1 Moment's Peace
2 Hydroblast if you see Gemhide Sliver or Mountain or Bladeback Sliver (swapping out the two Dinrova Horrors)

RDW
Sideboarding -
Out:
2 Dinrova Horror
3 Ghostly Flicker
1 Ephemerate
1 Dispel
1 Mulldrifter
1 Compulsive Research
In:
5 Blue Blasts
2 Lone Missionaries
1 Stonehorn Dignitary
1 Moment's Peace

Goblins
Sideboarding -
Out:
2 Dinrova Horror
3 Ghostly Flicker
1 Ephemerate
1 Dispel
1 Mulldrifter
1 Compulsive Research
In:
5 Blue Blasts
2 Lone Missionaries
1 Stonehorn Dignitary
1 Moment's Peace

Familiars
Sideboarding -
Out:
3 Stonehorn Dignitary
2 Moment's Peace
1 Plains
In:
4 Pyroblasts
If they have Red mana (Pyroblast)
2 Blue Blasts
If not
1 Shattering Pulse and keep in the Plains
Mono-Black Control
Sideboarding -
Out:
2 Moment's Peace
1 Dispel
In:
1 Stonehorn Dignitary
1 Shattering Pulse
1 Lone Missionary
1 Gut Shot instead of the Missionary if you see Crypt Rats
Other decks
UB Flicker/Teachings
Sideboarding -
Out:
3 Stonehorn Dignitary
2 Moment's Peace
1 Plains
In:
4 Pyroblast
1 Shattering Pulse
1 Lone Missionary
GB Aristocrats
Sideboarding -
Out:
1 Dispel
1 Pulse of Murasa
In:
1 Stonehorn Dignitary
1 Moment's Peace

Suicide Black
Sideboarding -
Out:
2 Dinrova Horror
1 Dispel
1 Ghostly Flicker
In:
1 Stonehorn Dignitary
1 Moment's Peace
2 Lone Missionary

Zombies
Sideboarding -
Out:
1 Dispel
2 Ghostly Flicker
2 Dinrova Horror
In:
1 Stonehorn Dignitary
1 Moment's Peace
1 Gut Shot
2 Lone Missionary
Reanimator
Sideboarding -
Out:
2 Moment's Peace
1 Dispel
2 Ghostly Flicker
In:
1 Stonehorn Dignitary
4 Blue Blasts

Infect
This matchup is good, even if it doesn't look it. They're slow if they don't spike a Glistener Elf, and they struggle against anti-combat cards even more than Stompy, since if they spend two pump spells and get them eaten by a Moment's Peace, they can have their clock pushed back several turns, more than enough time to find more anti-combat cards. Your counters are also all excellent. Yeah sometimes they just turn 1 Glistener, turn 2 Groundswell + Mutagenic Growth + another pump spell and getcha, but whatever. The UG versions have Dispel to fight Moment's Peace, but their manabase is nonfunctional and leads to even fewer turn 1 Glistener Elves, and their pump spells are much weaker.
Sideboarding -
Out:
1 Pulse of Murasa
2 Dinrova Horror
1 Condescend on the draw
1 Ghostly Flicker on the play
In:
1 Moment's Peace
1 Stonehorn Dignitary
1 Gut Shot
1 Shattering Pulse
Gut Shot kills all their creatures, Shattering Pulse kills Ichorclaw Myr, and killing one creature frequently means you've killed all the creatures your opponent has drawn. Other than that, try to stay alive and stop combat while keeping an eye out for something like Viridian Longbow if possible. If playing against UG Infect, bring in all four Pyroblasts (they kill/counter Blighted Agent and also trade for a number of their pump spells while allowing you to fight through Dispels) in exchange for a couple Mulldrifters and a couple more Flickers.