Have

Migratory Greathorn

Mutate {2}{G} (If you cast this spell for its mutate cost, put it over or under target non-Human creature you own. They mutate into the creature on top plus all abilities from under it.)
Whenever this creature mutates, search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Opulent Palace

This land enters tapped.
{T}: Add {B}, {G}, or {U}.

Carnivorous Canopy

Destroy target artifact, enchantment, or creature with flying. If that permanent's mana value was 3 or less, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Dissipation Field

Whenever a permanent deals damage to you, return it to its owner's hand.

Innkeeper's Talent

(Gain the next level as a sorcery to add its ability.)
At the beginning of combat on your turn, put a +1/+1 counter on target creature you control.
{G}: Level 2
Permanents you control with counters on them have ward {1}.
{3}{G}: Level 3
If you would put one or more counters on a permanent or player, put twice that many of each of those kinds of counters on that permanent or player instead.

Morphic Pool

This land enters tapped unless you have two or more opponents.
{T}: Add {U} or {B}.

Contagion Clasp

When this artifact enters, put a -1/-1 counter on target creature.
{4}, {T}: Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Jungle Hollow

This land enters tapped.
When this land enters, you gain 1 life.
{T}: Add {B} or {G}.

Ichorclaw Myr

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
Whenever this creature becomes blocked, it gets +2/+2 until end of turn.

Don't Have

Contaminant Grafter

Trample, toxic 1
Whenever one or more creatures you control deal combat damage to one or more players, proliferate.
Corrupted — At the beginning of your end step, if an opponent has three or more poison counters, draw a card, then you may put a land card from your hand onto the battlefield.

Reflecting Pool

{T}: Add one mana of any type that a land you control could produce.

Sunken Hollow

({T}: Add {U} or {B}.)
This land enters tapped unless you control two or more basic lands.

Auspicious Starrix

Mutate {5}{G} (If you cast this spell for its mutate cost, put it over or under target non-Human creature you own. They mutate into the creature on top plus all abilities from under it.)
Whenever this creature mutates, exile cards from the top of your library until you exile X permanent cards, where X is the number of times this creature has mutated. Put those permanent cards onto the battlefield.

Dismal Backwater

This land enters tapped.
When this land enters, you gain 1 life.
{T}: Add {U} or {B}.

Drown in Ichor

Target creature gets -4/-4 until end of turn. Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Silent Arbiter

No more than one creature can attack each combat.
No more than one creature can block each combat.

Cystbearer

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Dreamtide Whale

Vanishing 2 (This creature enters with two time counters on it. At the beginning of your upkeep, remove a time counter from it. When the last is removed, sacrifice it.)
Whenever a player casts their second spell each turn, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Beast

Myr Convert

Toxic 1 (Players dealt combat damage by this creature also get a poison counter.)
{T}, Pay 2 life: Add one mana of any color.

Vraska's Fall

Each opponent sacrifices a creature or planeswalker of their choice and gets a poison counter.

Phyresis

Enchant creature
Enchanted creature has infect. (It deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Thriving Isle

This land enters tapped. As it enters, choose a color other than blue.
{T}: Add {U} or one mana of the chosen color.

Reaper of Sheoldred

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
Whenever a source deals damage to this creature, that source's controller gets a poison counter.

Hand of the Praetors

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
Other creatures you control with infect get +1/+1.
Whenever you cast a creature spell with infect, target player gets a poison counter.

Deadly Rollick

If you control a commander, you may cast this spell without paying its mana cost.
Exile target creature.

Septic Rats

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
Whenever this creature attacks, if defending player is poisoned, it gets +1/+1 until end of turn.

Evolution Sage

Landfall — Whenever a land you control enters, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Dreamtail Heron

Mutate {3}{U} (If you cast this spell for its mutate cost, put it over or under target non-Human creature you own. They mutate into the creature on top plus all abilities from under it.)
Flying
Whenever this creature mutates, draw a card.

Gemrazer

Mutate {1}{G}{G} (If you cast this spell for its mutate cost, put it over or under target non-Human creature you own. They mutate into the creature on top plus all abilities from under it.)
Reach, trample
Whenever this creature mutates, destroy target artifact or enchantment an opponent controls.

Darkwater Catacombs

Boneyard Lurker

Mutate {2}{B/G}{B/G} (If you cast this spell for its mutate cost, put it over or under target non-Human creature you own. They mutate into the creature on top plus all abilities from under it.)
Whenever this creature mutates, return target permanent card from your graveyard to your hand.

Glistening Oil

Enchant creature
Enchanted creature has infect.
At the beginning of your upkeep, put a -1/-1 counter on enchanted creature.
When this Aura is put into a graveyard from the battlefield, return it to its owner's hand.

Golgari Signet

Phyrexian Crusader

First strike, protection from red and from white
Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Ram Through

Target creature you control deals damage equal to its power to target creature you don't control. If the creature you control has trample, excess damage is dealt to that creature's controller instead.

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Tezzeret's Gambit

({U/P} can be paid with either {U} or 2 life.)
Draw two cards, then proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Inexorable Tide

Whenever you cast a spell, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Forest

Grafted Exoskeleton

Equipped creature gets +2/+2 and has infect. (It deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
Whenever this Equipment becomes unattached from a permanent, sacrifice that permanent.
Equip {2}

Damnation

Destroy all creatures. They can't be regenerated.

Golgari Rot Farm

This land enters tapped.
When this land enters, return a land you control to its owner's hand.
{T}: Add {B}{G}.

Swamp

Otrimi, the Ever-Playful

Mutate {1}{B}{G}{U} (If you cast this spell for its mutate cost, put it over or under target non-Human creature you own. They mutate into the creature on top plus all abilities from under it.)
Trample
Whenever this creature deals combat damage to a player, return target creature card with mutate from your graveyard to your hand.

Thornwood Falls

This land enters tapped.
When this land enters, you gain 1 life.
{T}: Add {G} or {U}.

Propaganda

Creatures can't attack you unless their controller pays {2} for each creature they control that's attacking you.

Copy

(This token can be used to represent a token that's a copy of a permanent.)

Kodama's Reach

Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.

Beast Within

Destroy target permanent. Its controller creates a 3/3 green Beast creature token.

Ilysian Caryatid

{T}: Add one mana of any color. If you control a creature with power 4 or greater, add two mana of any one color instead.

Infectious Inquiry

You draw two cards and you lose 2 life. Each opponent gets a poison counter.

Spinebiter

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
You may have this creature assign its combat damage as though it weren't blocked.

Phyrexian Swarmlord

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
At the beginning of your upkeep, create a 1/1 green Phyrexian Insect creature token with infect for each poison counter your opponents have.

Skithiryx, the Blight Dragon

Flying
Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
{B}: Skithiryx gains haste until end of turn.
{B}{B}: Regenerate Skithiryx.

Rogue's Passage

{T}: Add {C}.
{4}, {T}: Target creature can't be blocked this turn.

Zagoth Triome

({T}: Add {B}, {G}, or {U}.)
This land enters tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Contagion Engine

When this artifact enters, put a -1/-1 counter on each creature target player controls.
{4}, {T}: Proliferate twice. (Choose any number of permanents and/or players, then give each another counter of each kind already there. Then do it again.)

Command Tower

Viral Drake

Flying
Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
{3}{U}: Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Beast Whisperer

Whenever you cast a creature spell, draw a card.

Plague Myr

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
{T}: Add {C}.

Armored Scrapgorger

This creature gets +3/+0 as long as it has three or more oil counters on it.
{T}: Add one mana of any color.
Whenever this creature becomes tapped, exile target card from a graveyard and put an oil counter on this creature.

Lifecrafter's Bestiary

At the beginning of your upkeep, scry 1.
Whenever you cast a creature spell, you may pay {G}. If you do, draw a card.

Foreboding Landscape

{T}: Add {C}.
{T}, Sacrifice this land: Search your library for a basic Swamp, Forest, or Island card, put it onto the battlefield tapped, then shuffle.
Cycling {B}{G}{U} ({B}{G}{U}, Discard this card: Draw a card.)

Path of Ancestry

This land enters tapped.
{T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Primal Empathy

At the beginning of your upkeep, draw a card if you control a creature with the greatest power among creatures on the battlefield. Otherwise, put a +1/+1 counter on a creature you control.

Venerated Rotpriest

Toxic 1 (Players dealt combat damage by this creature also get a poison counter.)
Whenever a creature you control becomes the target of a spell, target opponent gets a poison counter.

Darkslick Shores

This land enters tapped unless you control two or fewer other lands.
{T}: Add {U} or {B}.

Island

Sol Ring

Whispersilk Cloak

Equipped creature can't be blocked and has shroud. (It can't be the target of spells or abilities.)
Equip {2}

Chittering Harvester

Mutate {4}{B} (If you cast this spell for its mutate cost, put it over or under target non-Human creature you own. They mutate into the creature on top plus all abilities from under it.)
Whenever this creature mutates, each opponent sacrifices a creature of their choice.

Brokkos, Apex of Forever

Mutate {2}{U/B}{G}{G} (If you cast this spell for its mutate cost, put it over or under target non-Human creature you own. They mutate into the creature on top plus all abilities from under it.)
Trample
You may cast this card from your graveyard using its mutate ability.

Plague Stinger

Flying
Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Glowstone Recluse

Mutate {3}{G} (If you cast this spell for its mutate cost, put it over or under target non-Human creature you own. They mutate into the creature on top plus all abilities from under it.)
Reach
Whenever this creature mutates, put two +1/+1 counters on it.

Tainted Strike

Target creature gets +1/+0 and gains infect until end of turn. (It deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Rot Wolf

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
Whenever a creature dealt damage by Rot Wolf this turn dies, you may draw a card.

Unnatural Restoration

Return target permanent card from your graveyard to your hand. Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Whispering Specter

Flying
Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
Whenever this creature deals combat damage to a player, you may sacrifice it. If you do, that player discards a card for each poison counter they have.

Llanowar Wastes

{T}: Add {C}.
{T}: Add {B} or {G}. This land deals 1 damage to you.

Dimir Aqueduct

This land enters tapped.
When this land enters, return a land you control to its owner's hand.
{T}: Add {U}{B}.

Dirge Bat

Mutate {4}{B}{B} (If you cast this spell for its mutate cost, put it over or under target non-Human creature you own. They mutate into the creature on top plus all abilities from under it.)
Flash
Flying
Whenever this creature mutates, destroy target creature or planeswalker an opponent controls.

Glistener Elf

Thriving Grove

This land enters tapped. As it enters, choose a color other than green.
{T}: Add {G} or one mana of the chosen color.

Emergent Ultimatum

Search your library for up to three monocolored cards with different names and exile them. An opponent chooses one of those cards. Shuffle that card into your library. You may cast the other cards without paying their mana costs. Exile Emergent Ultimatum.

Flensermite

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Crawlspace

No more than two creatures can attack you each combat.

Simic Growth Chamber

This land enters tapped.
When this land enters, return a land you control to its owner's hand.
{T}: Add {G}{U}.

Blight Mamba

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
{1}{G}: Regenerate this creature.

Viridian Corrupter

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
When this creature enters, destroy target artifact.

Karn's Bastion

{T}: Add {C}.
{4}, {T}: Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)