Hi, I'm Gami and this is my Pioneer Soulflayer list! If you want to play a graveyard combo deck that isn't Greasefang, you're in the right place!
This deck is built to maximise the power of Soulflayer and Urborg Scavengers to apply early pressure with a hard to remove threat.

Deck Info:

>Noteable Inclusions:

Banehound - Blocking vs aggressive decks and/or forcing opponents to trade into these is very strong, especially when we don't mind if it dies. Makes the aggro matchups better game one. May become less relevant if you decide to swing the deck to play more aggro hate mainboard, but in this current version they're invaluable.

Samut, Voice of Dissent - This deck is less all-in on creatures for Soulflayer to delve than most, only having six main exile targets. Zetapla is fairly standard, Samut less so. The reason why, is that almost any combination of Samut and another creature, is fairly powerful, where other options needed three to four different creatures to have been milled to be a real threat without Zetalpa. This means we can run fewer threats overall and have much higher card quality.

Bitter Triumph - A card that interacts with the opponent while also furthering our gameplan.

Picklock Prankster - Seeing success in Phoenix, I thought it would be interesting to try here, digging for interaction or more gas while having two relevant keywords seems like a powerful combination.

>Noteable Exclusions:

Cragplate Baloth - Hexproof and haste is fine, but only really good as the first Urborg Scavengers target, even then, Scavengers can still be removed in response.

Adult Gold Dragon - A similar story, extra lifelink is good, but I don't think it's better than Samut. Losing the ability to hardcast it over something like the Aetherborns, Vampire of the Dire Moon or Banehound also isn't ideal, when the reason you'd want more lifelink is more aggro in the meta, so early blockers are key.

Neoform / Atraxa, Grand Unifier - There's an argument that the Atraxa Neoform variant is a better deck, but I think we can be equally consistent, if not more so, and pose a bigger, harder to remove threat, even if it doesn't refill our hand.

Founding the Third Path - I like this card a lot, it's able to colour fix, cast two spells in one for Ledger Shredder and reuse spells from the graveyard, a lot of what the deck wants to do. But there's one issue, we want to do as much as we can at instant speed, to be able to hold up countermagic and removal when it matters most, so this being a non-creature sorcery speed spell isn't where we want to be in this deck.

Lands - Nineteen is low, but when the most expensive card we're actually trying to cast in the deck is Urborg Scavengers at three mana and we have 17 ways to filter and draw cards at two mana or less, we can run a comparatively low number of lands while still being consistent. One or two land hands are perfectly keepable if they have 1-2 dig spells.
If we take into account the mana we actually intend to pay for each card, Soulflayer being BB, Striped Riverwinder being U etc..The average mana value of the maindeck is 1.60. Using Frank Karsten's fairly well respected method for calculating the minimum number of lands needed in a deck, that being 19.59 + (1.90 * average cmc) – (0.28 * cheap card selection spells), we get 19.59 + (1.90 * 1.60) – (0.28 * 17) = 17.87 lands, even counting Boseiju, Who Endures as half a land still gets us comfortably over this guideline, so hopefully that gives you some confidence!

>Currently Testing:

Bitter Triumph - A removal spell that also lets us discard a card has the potential to be very powerful in this deck.

Ashiok, Dream Render - Lotus will fold to this, as will most of the big mana Bring to Light or Enigmatic Incarnation decks. Three mana is actually relatively high for this deck but this will absolutely win games when it resolves.

Vampire of the Dire Moon - Cheaper than Gifted Aetherborn, meaning that triggering Ledger Shredder is easier, while being functionally identical in most situations.

Tainted Indulgence / Consider – Still deliberating whether being able to discard a dead card is worth it over something like Consider despite the extra mana cost. Indulgence can be a straight draw 2 in the grindy matches so that factors in as well.

Sideboard Theory:

> Rakdos (Midrange / Sacrifice):

Their Problem Cards:

Go Blank - Exiles graveyards, importantly sorcery speed.
Extinction Event - Kills any Soulflayer setup.
Liliana of the Veil - Can force us to sacrifice a Soulflayer, bypassing all our protection.
Unlicensed Hearse - Exiles graveyards at instant speed repeatably.
Sheoldred, the Apocalypse - Represents a clock that they don't need to attack with.

Game One:

Favoured for us, their only relevant interaction mainboard is Graveyard Trespasser and Bloodtithe Harvester because it gets around indestructible. Both are only at sorcery speed, so can be played around pretty easily.

Post-Board:

A little harder as any number of Extinction Event, Unlicensed Hearse, Liliana of the Veil, Sheoldred's Edict, Go Blank and Necromentia come in.
Be careful if Sacrifice reveals Jegantha, the Wellspring game one but not game two, this means they likely have brought in Leyline of the Void.
Gameplan is mostly the same, but this time we can answer their board a little more efficiently.

Changes:

In:
1x Abrupt Decay - Hits most threats and graveyard hate.
1x Assassin's Trophy - Can remove Sheoldred, the Apocalypse or any other problem permanent. Gives them a land, but a land should always be much less scary than the thing it removes.
1x Haywire Mite - Kills Leyline of the Void if they have it, otherwise it can hit other graveyard hate or Fable of the Mirror Breaker.

Out:
2x Thoughtseize - While hand disruption is good, it's a terrible draw when both players are low on resources.
1x Otherworldly Gaze - Going down on cards in the matchup where resources will be precious isn't great. We'd like a slightly higher card quality going in this matchup.

> Nykthos Ramp:

Their Problem Cards:

Karn, the Great Creator - Access to sideboard and silver bullets game 1.
Storm the Festival - Generates a lot of advantage that is difficult to come back from.
Nykthos, Shrine to Nyx - Nykthos is manageable as long as we can keep devotion off the board and answer whatever they play.
Kiora, Behemoth Beckoner - Untaps Nykthos and generates tons of mana.

Game One:

Tough, but winnable. If they get a good hand, we have to interact early or we lose, if they get a normal hand, interacting early makes it likely we win.
Keep them off high devotion if you can, don't focus desperately hard on getting a max-power Soulflayer, anything that fights a Cavalier and lives is good enough.

Post-Board:

Slightly better, but still not great. Nykthos almost never sideboards though, making Game 2-3 almost objectively better for us.
Assassin's Trophy is mostly there to disrupt their combo, hitting any Planeswalker or Nykthos itself. Can kill a Cavalier in a pinch if we need to push damage through.

Changes:

In:
2x Ray of Enfeeblement - These pretty much only hit the Llanowar Elves and Elvish Mystic, but when you can stop their early ramp the game becomes a lot easier to win.
2x Duress - Taking away their planeswalkers or other big plays can be very impactful.
1x Abrupt Decay - Removes devotion or Kiora, keeps them on their combat plan.
1x Assassin's Trophy - Removes any permanent that is presenting a threat.

Out:
2x Ledger Shredder - Blocking won't be much use unless we put 2+ counters on it, attacking won't be much use as Cavalier of Thorns and Polukranos Reborn have reach. Don't want to completely cut our discard outlets though.
2x Banehound - Lifelink and haste aren't key in this matchup, shaved for more relevant cards.
1x Striped Riverwinder - Outside of Karn wish targets, they have no way to remove a Soulflayer, and most of their wishboard doesn't deal with it well, going down a hexproof creatures is safe here.
1x Consider - Only one card in grave isn't fast enough here.

> Azorius Control:

Their Problem Cards:

Farewell - Exiles any Soulflayer setup.
Rest in Peace - Shuts down our entire gameplan
Absorb / Make Disappear - Counters our creatures, worst with Soulflayer who delves as a cost.

Game One:

Do not overextend, they have quite a few blowout cards, take your time, don't rush. Force them to use their interaction on less important things, if you suspect they have a counterspell and have the option, cast Scavengers first, as if it gets countered you still have cards in graveyard to use., Cast instants when/if they tap out on your end step. This is not a race.
Don't be afraid to cast Urborg Scavengers early with no value, if you think you can get them to resolve and start getting damage in, do. If you can start exiling relevant things as well, even better.

Post-Board:

Rest in Peace absolutely destroys our gameplan, so try to always have hand disruption or counters for it. Other than that, very similar to Game One but we have more disruption and they have Rest in Peace.

Changes:

In:
3x Mystical Dispute - Interacting early is key here, hitting RiP or resolving something through an Absorb is great.
2x Duress - For shredding their hand, keeping them low on resources and trying to pick a hole in their defences.
1x Assassin's Trophy - Answers any permanent.

Out:
2x Banehound - Not enough of a threat and keywords aren't the most useful
2x Abrupt Decay - Next to no targets in their deck. Some builds play Rest in Peace, but we should have enough countermagic and hand disruption to remove that before it ever hits the battlefield.
1x Otherworldly Gaze - Not needing to go as fast means we can trim the more all-in dig spells.
1x Bitter Triumph - This does hit Teferi, Hero of Dominaria and their other planeswalkers, but Assassin's Trophy is better as it's one more answer to Rest in Peace.

> Lotus Combo:

Their Problem Cards:

Lotus Field - Gives them the mana to win fast.
Emergent Ultimatum - Tutors for their combo
Languish / Sunfall - Kills any Soulflayer setup.

Game One:

Thoughtsieze their hand, apply pressure as fast as possible. We have relatively few ways to deal with their combo mainboard.

Post-Board:

Slightly better, as we have fewer dead cards, but the same still applies. Disruption and pressure wins games here.

Changes:

In:
3x Mystical Dispute - Catches a lot of important spells, most notably Emergent Ultimatum and Pore Over the Pages.
2x Duress - Taking draw / search spells and untap cards leaves them low on resources and buys us time to execute our plan.
1x Ashiok, Dream Render - Difficult to remove. Their passive ability is very disruptive and their -1 incidentally exiling their graveyard makes things harder too.

Out:
2x Banehound - Haste is nice, but lifelink doesn't help here and it's hard to argue that chip damage with a 1/1 is relevant. Playing something that does nothing to stop their gameplan, or further ours is an easy cut.
2x Abrupt Decay - Nothing to target.
1x Consider - Only one card in grave isn't fast enough here.
1x Striped Riverwinder - Very little targeted removal coming from Lotus so we can get away with less hexproof.

>Abzan Greasefang:

Their Problem Cards:

Greasefang, Okiba Boss - Reanimates and crews vehicles.
Parhelion II - Cheated into play.
Liliana of the Veil - Can force us to sacrifice a Soulflayer, bypassing all our protection.
Unlicenced Hearse - Disrupts our Soulflayer delve fuel.

Game One:

Getting a strong Soulflayer is borderline game over. Both decks combo at similar speeds, but we have seven threats and they only have four, some are running six if you count Eldritch Evolution or Traverse the Ulvenwald, but these take much more time than the dreaded turn three Greasefang.

Post-Board:

They have more removal sideboard, with Liliana of the Veil and sometimes Vanishing Verse, so now the requirement for an immoveable Soulflayer is hexproof, indestructible and to have one other creature on board. Matchup feels like it leans in our favour.

Changes:

In:
2x Ray of Enfeeblement - Kills Greasefang.
1x Abrupt Decay - Kills Greasefang and a variety of other things that stop our gameplan like Unlicensed Hearse.
1x Ashiok, Dream Render - Hard for them to remove and repeatedly exiles their graveyard. They'll have to combo all in one turn to dodge us exiling Parhelion.
1x Haywire Mite - Kills vehicles in response to them crewing. Be careful to sacrifice it in response to the crew trigger as Mite specifies a non-creature artifact. If you try before they can crew it in response, making it no longer a legal target.
1x Assassin's Trophy - Destroys any permanent, no questions asked, also hits Leyline of the Void if they're running it.

Out:
2x Banehound - Lifelink is nice, but is only good if we're racing. We'd rather have something that disrupts their combo completely than something that makes it less impactful.
2x Spell Pierce - Few important non-creature spells.
1x Striped Riverwinder - They have relatively little removal, so one copy can come out.
1x Consider - Only one card in grave isn't fast enough here.

> Creativity (Temur / Izzet):

Their Problem Cards:

Indomitable Creativity - Main path to them winning the game
Make Disappear - Hits creatures, can't be stopped by a single counterspell if they cast it with Casualty.
Disdainful Stroke - Only good against Soulflayer, so they might not bring it in, but something to be aware of
Divide by Zero - Counterspell or bounce spell, makes hexproof important.

Game One:

Temur needs to get to five mana and two tokens to flip into Worldspine Wurm and Xenagos, God of Revels to one-shot the opponent. Izzet only needs four and one, but their payoff is much less impactful.
Soulflayer can combo faster than creativity and then play the control game, but there's an element of luck to it, the matchup isn't terrible, but you need to be careful. Either resolve Soulflayer fast and close the game, or wait until they're low on resources and capitalise.
The plan game one is simply to resolve a Soulflayer, doesn't have to be particularly strong, just hexproof or indestructible will do. Once we have pressure, hold up mana and counter any attempts to cast Indomitable Creativity.

Post-Board:

After boarding it's quite similar. Take your time and be ready for a fight on the stack.

Changes:

For Both:

In:
3x Mystical Dispute - More disruption early, hits their counters and makes sure our threats resolve.
2x Duress - Taking their combo pieces or interaction, either slowing them down or poking a hole for us to combo through.

Out:
2x Banehound - Haste and lifelink aren't impactful enough against combo control.
2x Abrupt Decay - Hits Fable and tokens, but otherwise, not worth it against a majority spell based deck.
1x Stubborn Denial - Paying 1 isn't too difficult as the game goes longer, after we've resolved a Soulflayer, having a hard counter matters a lot less. We can rely on the Mystical Disputes and Spell Pierces to do the job.

For Izzet:

In:
1x Ashiok Dream Render - They care about their graveyard, as without it Torrential Gearhulk is just a 6/6.

Out:
1x Bitter Triumph - Their only creatures are essentially instants that happen to come attached to a body. Removal for them is much less valuable.

>Mono-White Humans:

Their Problem Cards:

Brutal Cathar - Exiles a non-hexproof Soulflayer. Even if we get it back, it loses the keywords.
Rest in Peace - Shuts down our Soulflayer gameplan.
Thalia, Guardian of Thraben - as a low curve deck with few lands, adding 30-50% to the cost of our spells hurts.

Game One:

Has the potential to be one of our worst matchups.
Will be difficult to win this one unless you run pretty well on your mill and draw. They can't beat a full Soulflayer setup, but they will not give little time to get there. Prioritize lifelink, hexproof and blockers first. hope to close the gates before they kill us.

Post-Board:

Quite a bit better with plenty of sideboard cards in. Same as game one, prioritize lifelink and hexproof to make an impossible to remove Soulflayer as soon as possible.

Changes:

In:
2x Ray of Enfeeblement - Hits every creature in the deck.
2x Vampire of the Dire Moon - Makes combat difficult, another source of lifelink for Soulflayer.
2x Path of Peril - Can be used to come back from the jaws of defeat.
1x Abrupt Decay - Hits every creature and Rest in Peace.

Out:
4x Thoughtseize - Hand interaction is much less important in the aggro matchup.
2x Spell Pierce - Can hit Ossification or RiP, but mostly dead.
1x Consider - Only one card into graveyard isn't fast enough here

>Spirits (Mono-Blue / Azorius / Bant):

Their Problem Cards:

Lofty Denial / Geistlight Snare - Easily counters a Soulflayer
Rest in Peace - Shuts down our Soulflayer gameplan.

Game One:

As with most aggro decks, they can't beat a resolved Soulflayer with good keywords, they offer similar pressure to other aggro decks and significantly more disruption.
Game one should be relatively straightforward, if difficult. Block with Ledger Shredders, fight through disruption, resolve a Soulflayer when you can, win from there.

Post-Board:

Mostly the same, apart from the vague threat of turn two Rest in Peace, if this happens our gameplan turns to Shredders, no-value Scavengers and trying to find Abrupt Decay. It's harder, but not impossible. Most lists seem to have steered away from RiP, so hopefully your Spirits opponent has too.

Changes:

In:
3x Mystical Dispute - Will hit most, if not all of their spells.
2x Path of Peril - Can be used to come back from the jaws of defeat.
1x Abrupt Decay - Removes RiP if they have it, safely destroys any threat as it can't be countered.

Out:
4x Thoughtseize - Their creature are their card draw, so removing their attackers is our form of resource denial.
1x Striped Riverwinder - They run 3-4 removal spells sideboard, but often we can counterspell these. Once we have a Soulflayer in play, little else matters, so all our counters can become protection for our threat.
1x Consider- Only one card into graveyard isn't fast enough here

>Mono Red Aggro:

Their Problem Cards:

Kari Zev's Expertise - Can steal a Soulflayer without a full setup.
Roast - Kills a Soulflayer without indestructible or flying.

Game One:

They will be fast, but have literally no way to remove a resolved Soulflayer, if we get indestructible and lifelink, it's basically game over.

Post-Board:

Very similar, but we have more disruption, eight damage a turn is hard to race, especially if they're losing attackers running into a Soulflayer with vigilance.

Changes:

In:
2x Vampire of the Dire Moon - Makes combat difficult and getting lifelink on a Soulflayer wins us the game.
2x Path of Peril - Can be used to come back from the jaws of defeat.
1x Haywire Mite - Blocking a large attacker and gaining two life is surprisingly relevant, can also hit any graveyard hate they may have.

Out:
3x Thoughtseize - The life loss hurts more than it helps here
1x Spell Pierce - Countering their burn spells is fine, but we want to focus on their creatures more. Trimmed one.
1x Consider - Only one card into graveyard isn't fast enough here

*Less Tested Matchups

> Gruul Midrange:

Their Problem Cards:

Skysovereign, Consul Flagship - Very evasive to all of our removal as it'll most likely only be a creature on their turn. Needs a Zetalpa Soulflayer to get through it.
The Akroan War - Will steal a non-hexproof Soulflayer for multiple turns.
The Stone Brain - Can exile our Soulflayers if they get it down fast enough.
Klothys, God of Destiny / Unlicensed Hearse - Repeatable graveyard hate, notably Klothys can't be removed by Abrupt Decay or countered by any counterspells we have, luckily, it's much easier to play through than Hearse.

Changes:

In:
2x Ray of Enfeeblement - These pretty much only hit the Llanowar Elves and Elvish Mystic, but when you can stop their early ramp the game becomes a lot easier to win.
1x Abrupt Decay - Destroys every creature in the deck.
1x Assassin's Trophy - For destroying Skysovereign or The Akroan War
1x Haywire Mite - We have to use this in response to them crewing a vehicle, as it specifies non-creature, but can really swing the tempo back in our favour.

Out:
2x Thoughtseize - They're a very resilient deck, so throwing away a card isn't as impactful.
2x Banehound - Only good as a chump blocker, lifelink isn't relevant most of the time.
1x Consider - Only one card into graveyard isn't fast enough here

> Selesnya Angels:

Their Problem Cards:

Shapers' Sanctuary - To slow them down enough to set up Soulflayer, we're going to need to remove their creatures, Sanctuary gaining them a card each time we do is pretty bad.
Rest In Peace - Shuts down the graveyard.

Changes:

In:
2x Ray of Enfeeblement - Removes any creature for one mana, great way to stop their early developments.
1x Abrupt Decay - Removes every non-land permanent in their deck, including RiP

Out:
2x Banehound - Lifelink is nice, but they have too much inevitability for us to win by drawing the game out.
1x Consider - Only one card into graveyard isn't fast enough here, we need to race Angels to win.

>Izzet Phoenix:

Their Problem Cards:

Thing in the Ice - Can force us to return a Soulflayer to our hand if it flips.
Disdainful Stroke - Counters our Soulflayer.

Changes:

In:
3x Mystical Dispute - Will hit all of their counters
1x Ashiok, Dream Render - Incidentally exiling their graveyard is very strong as they're very reliant on it.

Out:
2x Spell Pierce- Bringing in Mystical Dispute means that we can afford to cut the worse counterspell.
1x Striped Riverwinder - They run limited removal. We should aim to have counterspells up or have already discarded their tempo plays, so going down on other angles of protection is fine.
1x Considere - Only one card into graveyard isn't fast enough here

>Five-Colour Fires:

Their Problem Cards:

Fires of Invention - One of the engines of the deck.
Enigmatic Incarnation - One of the engines of the deck.
Rest in Peace / Leyline of the Void - Shuts down our entire gameplan.
Various targeted exile effects - Need Hexproof.

Changes:

In:
2x Duress - They are heavily enchantment based so this can take a lot of relevant cards.
1x Assassin's Trophy - Kills the bigger threats if they have time to stabilise.
1x Haywire Mite - Removes all their value enchantments.
1x Ashiok, Dream Render - Turning off their searches is great as it slows down one of the main engines of their deck.

Out:
2x Banehound - Chip damage isn't relevant.
2x Abrupt Decay - They rarely have impactful targets to hit with this.
1x Otherworldly Gaze - The game will likely go long, so we can afford to cut some of our more all-in dig spells.

>Omnath Bring to Light:

Their Problem Cards:

Bring to Light - The engine of the deck.
Rest in Peace - Shuts down our entire gameplan.
Various targeted exile effects - Need Hexproof.
Slaughter Games - Uncounterable Necromentia that can be searched for relatively early.

Changes:

In:
2x Duress - Takes their early enchantment plays and should slow them down enough that we have time to combo.
1x Mystical Dispute - Counters Bring To Light and Omnath, but a lot of their deck isn't blue, so don't bring in the full three.
1x Haywire Mite - They still have a few big enchantments to hit.
1x Ashiok, Dream Render - Stopping them searching turns off their main value engine.

Out:
2x Banehound - Chip damage isn't relevant.
2x Abrupt Decay- They rarely have creatures small enough to hit with this.
1x Otherworldly Gaze - The game will naturally go longer so we can afford to cut some of our more all-in dig spells.

>Boros Convoke:

Their Problem Cards:

Gleeful Demolition - Essentially Dark Ritual in this deck, insane acellarant.
Venerated Loxodon - Gives a buff to their creatures and adds a medium sized body.
Reckless Bushwhacker - Turns a small push into a lethal attack.
Knight-Errant of Eos - Draws them cards and allows them to keep up pressure.

Changes:

In:
2x Ray of Enfeeblement - Removes their one drops or bigger threats.
2x Vampire of the Dire Moon - Extra sources of lifelink help us stabilise and make it harder for them to put up as much if a clock.
2x Path of Peril - Wipes all their smaller tokens and lets us stabilise.

Out:
2x Stubborn Denial - Only really hits Gleeful Demolition.
2x Abrupt Decay - Their deck is designed to punish 1 for 1 removal spells, Doesn't get enough value here.
1x Consider - Only one card into graveyard isn't fast enough here
1x Striped Riverwinder - Next to no removal in their deck. A Giant Killer is all that we need to worry about.

>Boros Pia Aggro:

Their Problem Cards:

Chained to the Rocks - Not awful as we have enchantment removal and hexproof, but something to watch out for.
Pia Nalaar, Consul of Revival - Goes very wide if left unchecked.

Changes:

In:
2x Path of Peril - Wipes almost every creature in their deck.
2x Vampire of the Dire Moon - Extra lifelink slows down their clock or wins us the game if we get an immoveable Soulflayer.
1x Abrupt Decay - Some decks run Rest In Peace, this hits that while also removing creatures if needed. Also hits Invasion of Gobakahn from the board.

Out:
3x Thoughtseize - They are a resilient deck with lots of card advantage, Thoughtseize loses it's value.
1x Consider - Only one card into graveyard isn't fast enough here
1x Spell Pierce- Hitting their spells is fine, but they already get value on cast from Pia.

>Lotus Control:

Their Problem Cards:

Strict Proctor - Slows down Urborg Scavengers, allows them to play Lotus Field with no downside.
Discontinuity - We need to be careful doing things on their end step as they can just exile our spell for two mana, as with regular control, we have to wait until we have counterspell backup or they tap out before trying anything important.
Sunfall / Farewell - Three exile-based wraths mainboard is difficult, watch out for these and be ready to fight them.
Rest in Peace - Shuts down our gameplan hard.

Changes:

In:
3x Mystical Dispute - Interacting early is key here, hitting Teferi or resolving something through an Absorb is great.
2x Duress - For shredding their hand, keeping them low on resources and trying to pick a hole in their defences.

Out:
2x Banehound - Not enough of a threat and keywords aren't the most useful
2x Abrupt Decay - While this can remove Strict Proctor, it doesn't hurt our gameplan too much and Push is dead everywhere else
1x Otherworldly Gaze - The earlier turns will be spent interacting, so going down some Gazes here feels safe. Don't need to fill the graveyard as fast.