Symbiotic Swarm precon upgrade guide

Kathril checks eleven keywords against your graveyard, and four of them (first strike, hexproof, menace and reach) are printed on exactly one creature card each in this box. The upgrade closes those four gaps first.

Kathril, Aspect Warper costs five and does her work once, as she enters. For each of eleven keywords, if a creature card in your graveyard has it, one counter of that keyword goes on a creature you control. Then she gets a +1/+1 counter for every counter that went out. Two rulings shape the maths: it’s one counter per keyword however many cards have it, and the counters can be split across different creatures. The ceiling is eleven keyword counters and eleven +1/+1 counters. What you actually get depends on how many of the eleven keywords are sitting in the graveyard when she lands.

That’s a question about the box’s creature cards, and they can be counted. There are 34 of them in the 99. Flying is printed on ten, vigilance on seven, deathtouch on six and trample on five. Double strike and lifelink are on three each, indestructible on two. First strike, hexproof, menace and reach are on one each: Akroma, Angel of Wrath, Slippery Bogbonder, Nikara, Lair Scavenger and Nyx Weaver. Akroma costs eight mana, and no other creature in the deck prints first strike.

So the engine stays as it is. The swaps go into those four gaps, into a mana base where three tapped lands do nothing but fix, and into a handful of cards that never touch your own board.

What are the best Symbiotic Swarm upgrades?

Prices are the cheapest paper printing as of 9 October 2026, and the list runs in the order I would buy.

1. Hit-Monkey ($2.44): reach, vigilance, deathtouch, hexproof and haste on a four-mana 3/3. It fills two of the four one-card gaps by itself.
2. Glissa Sunslayer ($0.61): first strike and deathtouch for three mana, and the only creature besides Akroma that prints first strike. Connecting with her can draw a card.
3. Syr Vondam, Sunstar Exemplar ($0.42): menace and vigilance on a two-drop. It’s the second menace in the deck.
4. Sylvan Caryatid ($1.01) and Poison Dart Frog ($0.33): two mana creatures that tap for any colour. Between them they add hexproof and reach.
5. Winding Constrictor ($0.46): every counter placed on your creatures arrives with one extra.
6. Restoration Angel ($0.31): flash, flying, and it can reset a creature that has an enters trigger.
7. Beast Whisperer ($3.99): a card for every creature spell, in a deck with 38 creature cards.
8. Temple Garden ($6.71), Overgrown Tomb ($8.77) and Isolated Chapel ($0.23): untapped lands in place of three that enter tapped. They come last because the two shocks are due a reprint.

Eleven cards come out to make room, and the cut list is below. The eleven adds cost $25.28 together.

Closing the four one-card gaps

After the swaps, the lowest count anywhere is two. First strike is on Akroma and Glissa Sunslayer. Hexproof is on Slippery Bogbonder, Hit-Monkey and Sylvan Caryatid. Menace is on Nikara and Syr Vondam. Reach is on Nyx Weaver, Hit-Monkey and Poison Dart Frog. Deathtouch goes from six cards to eight, and flying, vigilance, lifelink and trample end where they started. Indestructible and double strike are the two I left thin, at two and three. Each card above fills more than one gap, so they didn’t earn a swap.

Every one of the new bodies costs two to four mana. That matters because a graveyard on turn five or six is filled by whatever traded in combat early, and a two-drop reaches combat sooner than Akroma ever will. I can’t compute when a given creature dies. I can say which cards are cheap enough to get the chance.

The list adds no self-mill, because the box already has six cards whose job is to fill the yard: Splinterfright and Nyx Weaver mill two each upkeep, Satyr Wayfinder, Grisly Salvage and Selective Adaptation put the rest of what they reveal into it, and Deadbridge Chant mills ten. Void Beckoner and Titanoth Rex are two more, and I’ll explain those with the keeps.

Seven Plains, seven Swamps, four Forests

Thirty-eight lands sits at the top of the usual range, and ten of them enter tapped. The basics are split 7 Plains, 7 Swamps and 4 Forests, which is odd for a deck where green is a third of the commander’s identity. Counting the three mana rocks, Exotic Orchard and the four lands that search out another land as sources, green has 20 of them against 27 green spells, and the odds of having green by turn two come out at 84.8%. Black, with 22 sources, gets there 87.7% of the time and white, with 24, 90.1%. Six cards fetch basic lands (Cultivate, Sakura-Tribe Elder, Evolving Wilds, Deathsprout, Myriad Landscape and Blighted Woodland) and only four basics in the whole deck are Forests.

Three of the ten tapped lands are the ones to replace. Blossoming Sands, Jungle Hollow and Scoured Barrens enter tapped, gain a life and tap for one of two colours, which makes them slower versions of the untapped duals that exist for these pairs. Temple Garden, Overgrown Tomb and Isolated Chapel cover the same three pairs. The two shocks cost two life to enter untapped, and they’re Forests, which matters here: Karametra and Krosan Verge both search for a Forest card, and a Forest card can be a dual land. Isolated Chapel enters untapped if you control a Plains or a Swamp, and the deck has fourteen basic Plains and Swamps, and Canopy Vista and both shocks count as well.

The swaps are colour for colour, so only one land source moves, and it is the Forest point above: Krosan Verge can now find Overgrown Tomb, so it counts for black as well. The tapped-land count does move, from ten to seven. The rest comes from the two mana creatures, and together that takes green from 20 to 22, black from 22 to 25 and white from 24 to 26. I’d discount the creatures. The calculator counts a creature as a source from turn one, and a creature cast on turn two taps on turn three. On the same count, the chance of green on time goes from 84.8% to 87.7% even though the deck now has five more green spells, and the double-black check by turn three goes from 63.9% to 71.8%.

Eleven cards leave, and three of them are lands

• Predatory Impetus, Martial Impetus and Parasitic Impetus: Auras that go on somebody else’s creature, give it a bonus and goad it. Parasitic Impetus drains two a swing and Martial Impetus pumps the other attackers, but all three need an opponent’s creature to survive and attack, and none adds a counter or a keyword to your own board. The deck has seventeen cards that do.
• Cataclysmic Gearhulk: each player chooses one artifact, one creature, one enchantment and one planeswalker, and sacrifices the other nonland permanents. It would leave me one artifact and one enchantment, in a deck with Sol Ring, Arcane Signet and the other rocks, Karametra and Abzan Ascendancy, and every creature but one. Duneblast does the sweeping job and stays, because it destroys rather than sacrifices, so Zetalpa survives it whether or not it’s the creature you pick.
• Unbreakable Bond: five mana for one creature back with a lifelink counter. Ever After returns two for six, and Unburial Rites has a flashback.
• Kalemne's Captain: a 5/5 vigilance body, which is fine. The monstrosity costs seven and exiles every artifact and enchantment, mine included.
• Daring Fiendbonder: a 5/1 haste for four that has to attack each combat. Its graveyard ability is real, and I’ll miss it, but a card that has to die to be useful isn’t what I want in the slot.
• Cartographer's Hawk: a 2/1 flier, in the keyword the deck already has the most of.
• Blossoming Sands, Jungle Hollow and Scoured Barrens: the three tapped lands above.

Why the expensive cards stay

Void Beckoner costs eight and Titanoth Rex costs nine, and I’d rarely cast either for that. Cycling costs {2}{B} and {1}{G}, and cycling puts a deathtouch counter or a trample counter on a creature you control. It also drops a creature card with deathtouch or trample into the graveyard, which is the exact thing Kathril is checking for. Two of the deck’s most expensive cards are among the cheapest ways it has of feeding her.

Deadbridge Chant is a six-drop that mills ten cards on the way in, and then, every upkeep, takes a random card from the graveyard: a creature goes straight to the battlefield and anything else goes to your hand. Soul of Innistrad has deathtouch and returns three creatures to your hand for {3}{B}{B}. Ajani Unyielding reveals three cards for nonland permanents and exiles a creature. These are all expensive, and each is doing a different job in the same plan.

Seven lands still enter tapped after the swaps, and six of them earn it. The three bounce lands (Golgari Rot Farm, Orzhov Basilica and Selesnya Sanctuary) tap for two mana. Krosan Verge and Myriad Landscape sacrifice themselves for two lands and Memorial to Folly returns a creature card to your hand. Sandsteppe Citadel only fixes, and it fixes all three colours.

Doing Kathril twice

She does her work on entering, so anything that makes her enter again does it again. Restoration Angel exiles a non-Angel creature you control and returns it, at instant speed, and Kathril is a Nightmare Insect. Her own +1/+1 counters disappear when she’s exiled, because the creature that returns is a new object, but the keyword counters on other creatures stay and she gets a fresh run at the graveyard. The Angel also targets Reveillark, which returns up to two creature cards with power 2 or less when it leaves, and Hornet Queen, which makes four more deathtouch fliers.

Winding Constrictor sits at the other end. Fifteen cards in the 99 put counters on creatures after the swaps, and with the Constrictor out, each placement arrives with one more. Abzan Ascendancy puts two +1/+1 counters on each creature instead of one, and so does Gavony Township. I haven’t claimed anything about how it interacts with Kathril’s own count, because the rulings don’t say.

What the money went on, and what I left in the shop

The eleven adds come to $25.28, as the cheapest paper printing stood on 9 October 2026. The eight spells are $9.57 and the three lands are $15.71, of which $15.48 is the two shocks. All ten shocklands, including Temple Garden and Overgrown Tomb, are reprinted in Star Trek on 13 November 2026, so I’d expect those two to get cheaper. If you’d rather spend nothing on lands, Woodland Cemetery ($0.63) and Sunpetal Grove cover the two green pairs for $0.89 together, though neither is a Forest.

I skipped Godless Shrine ($8.64). It would be a third shock for a colour pair that Isolated Chapel covers for twenty-three cents. Doubling Season ($30.00) is the card I’d buy next if you want more from the counters. It doubles both counters and tokens, including Hornet Queen’s four Insects, and it’s the one I skipped on price. Guardian Project ($13.18) is a draw engine in a singleton deck, where its same-name condition rarely applies, and Beast Whisperer does a similar job for $3.99.

Nothing named on this page is a Game Changer, skipped cards included, and the site’s bracket check finds nothing in the box or the swaps that raises the floor above Bracket 1.

The upgraded decklist

The full hundred after the swaps. Hover any card name to see the card.

Load into the deck builder Copy decklist Playtest the upgraded deck

“Load into the deck builder” opens this list in your account, pinned to the printings the box shipped, ready to edit or save. “Copy decklist” gives you plain text for Moxfield, Archidekt or Arena — no account needed.

FAQ

How many counters can Kathril put out in one go?

Eleven keyword counters at most, and a +1/+1 counter on her for each one. It’s one counter per keyword however many creature cards in the graveyard have it, so a flier, a deathtoucher and a trampler in the yard give you three counters to place and a Kathril that grows by three. The counters can go on any creatures you control, including her, and they don’t all have to go on the same one.

Does cycling Void Beckoner or Titanoth Rex help her?

Yes, twice over. Each is a creature card the moment it’s in the graveyard, and Void Beckoner has deathtouch while Titanoth Rex has trample, so cycling either one fills a keyword Kathril checks. The cycling trigger also puts a deathtouch or trample counter on a creature you control, for {2}{B} or {1}{G}.

Can Restoration Angel flicker Kathril?

It can, because she’s a Nightmare Insect and the Angel only refuses Angels. She enters again and her trigger runs again against whatever is in the graveyard by then. Her own +1/+1 counters are gone, since the creature that returns is a new object, but the keyword counters she put on other creatures stay.

What does the upgrade cost, and can it cost less?

$25.28 for all eleven cards at the cheapest paper printing on 9 October 2026. The eight spells are $9.57 and the three lands are $15.71. Swap Temple Garden and Overgrown Tomb for Woodland Cemetery and Sunpetal Grove and the whole list comes to $10.69. Those two checklands aren’t Forests, so Karametra and Krosan Verge can’t fetch them.

Is green really the short colour with only four Forests?

It is. The deck has 20 green sources against 27 green spells, which puts green on time by turn two 84.8% of the time against 87.7% for black and 90.1% for white. Six cards fetch basic lands and the 18 basics are 7 Plains, 7 Swamps and 4 Forests. The swaps don’t change a green land source, only whether the lands enter tapped, so the improvement in green comes from the two mana creatures.

Could Nikara and Yannik lead the deck instead of Kathril?

They’re legal, since each says it partners with the other and together they cover black, green and white. They play a different game, though. Nikara draws a card when a creature with counters leaves the battlefield, and Yannik exiles one of your creatures and spreads counters equal to its power. Neither cares about the graveyard, which is the part of this deck the swaps were built around.