Forgotten Ancient

Whenever a player casts a spell, you may put a +1/+1 counter on Forgotten Ancient.
At the beginning of your upkeep, you may move any number of +1/+1 counters from Forgotten Ancient onto other creatures.

Inexorable Blob

Delirium — Whenever Inexorable Blob attacks, if there are four or more card types among cards in your graveyard, create a 3/3 green Ooze creature token that's tapped and attacking.

Momentous Fall

As an additional cost to cast this spell, sacrifice a creature.
You draw cards equal to the sacrificed creature's power, then you gain life equal to its toughness.

Splitting Slime

{4}{G}{G}: Monstrosity 3. (If this creature isn't monstrous, put three +1/+1 counters on it and it becomes monstrous.)
When Splitting Slime becomes monstrous, create a token that's a copy of Splitting Slime. (The token has no counters and isn't monstrous.)

Jiang Yanggu, Wildcrafter

Each creature you control with a +1/+1 counter on it has "{T}: Add one mana of any color."
−1: Put a +1/+1 counter on target creature.

Gelatinous Genesis

Fertilid

Fertilid enters the battlefield with two +1/+1 counters on it.
{1}{G}, Remove a +1/+1 counter from Fertilid: Target player searches their library for a basic land card, puts it onto the battlefield tapped, then shuffles.

Path of Discovery

Whenever a creature enters the battlefield under your control, it explores. (Reveal the top card of your library. Put that card into your hand if it's a land. Otherwise, put a +1/+1 counter on the creature, then put the card back or put it into your graveyard.)

Emerald Medallion

Green spells you cast cost {1} less to cast.

Nissa's Judgment

Support 2. (Put a +1/+1 counter on each of up to two target creatures.)
Choose up to one target creature an opponent controls. Each creature you control with a +1/+1 counter on it deals damage equal to its power to that creature.

Inspiring Call

Draw a card for each creature you control with a +1/+1 counter on it. Those creatures gain indestructible until end of turn. (Damage and effects that say "destroy" don't destroy them.)

Hickory Woodlot

Hickory Woodlot enters the battlefield tapped with two depletion counters on it.
{T}, Remove a depletion counter from Hickory Woodlot: Add {G}{G}. If there are no depletion counters on Hickory Woodlot, sacrifice it.

Wave of Vitriol

Each player sacrifices all artifacts, enchantments, and nonbasic lands they control. For each land sacrificed this way, its controller may search their library for a basic land card and put it onto the battlefield tapped. Then each player who searched their library this way shuffles.

Biowaste Blob

Oozes you control get +1/+1.
At the beginning of your upkeep, if you control a commander, create a token that's a copy of Biowaste Blob.

Heroic Intervention

Permanents you control gain hexproof and indestructible until end of turn.

Aeve, Progenitor Ooze

Storm (When you cast this spell, copy it for each spell cast before it this turn. Copies become tokens.)
Aeve, Progenitor Ooze isn't legendary if it's a token.
Aeve enters the battlefield with a +1/+1 counter on it for each other Ooze you control.

Ranger's Guile

Target creature you control gets +1/+1 and gains hexproof until end of turn. (It can't be the target of spells or abilities your opponents control.)

Gobbling Ooze

{G}, Sacrifice another creature: Put a +1/+1 counter on Gobbling Ooze.

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.

Retreat to Kazandu

Landfall — Whenever a land enters the battlefield under your control, choose one —
• Put a +1/+1 counter on target creature.
• You gain 2 life.

Invigorating Surge

Put a +1/+1 counter on target creature you control, then double the number of +1/+1 counters on that creature.

Crashing Drawbridge

Defender
{T}: Creatures you control gain haste until end of turn.

Gladehart Cavalry

When Gladehart Cavalry enters the battlefield, support 6. (Put a +1/+1 counter on each of up to six other target creatures.)
Whenever a creature you control with a +1/+1 counter on it dies, you gain 2 life.

Experiment One

Evolve (Whenever a creature enters the battlefield under your control, if that creature has greater power or toughness than this creature, put a +1/+1 counter on this creature.)
Remove two +1/+1 counters from Experiment One: Regenerate Experiment One. (The next time this creature would be destroyed, instead tap it, remove it from combat, and heal all damage on it.)

Hunter's Insight

Choose target creature you control. Whenever that creature deals combat damage to a player or planeswalker this turn, draw that many cards.

Oran-Rief, the Vastwood

Oran-Rief, the Vastwood enters the battlefield tapped.
{T}: Add {G}.
{T}: Put a +1/+1 counter on each green creature that entered the battlefield this turn.

Vorinclex, Monstrous Raider

Trample, haste
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.
If an opponent would put one or more counters on a permanent or player, they put half that many of each of those kinds of counters on that permanent or player instead, rounded down.

Pir, Imaginative Rascal

Partner with Toothy, Imaginary Friend (When this creature enters the battlefield, target player may put Toothy into their hand from their library, then shuffle.)
If one or more counters would be put on a permanent your team controls, that many plus one of each of those kinds of counters are put on that permanent instead.

Avenger of Zendikar

When Avenger of Zendikar enters the battlefield, create a 0/1 green Plant creature token for each land you control.
Landfall — Whenever a land enters the battlefield under your control, you may put a +1/+1 counter on each Plant creature you control.

Charge Through

Target creature gains trample until end of turn.
Draw a card.

Death's Presence

Whenever a creature you control dies, put X +1/+1 counters on target creature you control, where X is the power of the creature that died.

Hardened Scales

If one or more +1/+1 counters would be put on a creature you control, that many plus one +1/+1 counters are put on it instead.

Predatory Hunger

Enchant creature
Whenever an opponent casts a creature spell, put a +1/+1 counter on enchanted creature.

Door of Destinies

As Door of Destinies enters the battlefield, choose a creature type.
Whenever you cast a spell of the chosen type, put a charge counter on Door of Destinies.
Creatures you control of the chosen type get +1/+1 for each charge counter on Door of Destinies.

Corrosive Ooze

Whenever Corrosive Ooze blocks or becomes blocked by an equipped creature, destroy all Equipment attached to that creature at end of combat.

Bioplasm

Whenever Bioplasm attacks, exile the top card of your library. If it's a creature card, Bioplasm gets +X/+Y until end of turn, where X is the exiled creature card's power and Y is its toughness.

Gluttonous Slime

Flash
Devour 1 (As this enters the battlefield, you may sacrifice any number of creatures. This creature enters the battlefield with that many +1/+1 counters on it.)

Regal Force

When Regal Force enters the battlefield, draw a card for each green creature you control.

Vigor

Trample
If damage would be dealt to another creature you control, prevent that damage. Put a +1/+1 counter on that creature for each 1 damage prevented this way.
When Vigor is put into a graveyard from anywhere, shuffle it into its owner's library.

Rishkar, Peema Renegade

When Rishkar, Peema Renegade enters the battlefield, put a +1/+1 counter on each of up to two target creatures.
Each creature you control with a counter on it has "{T}: Add {G}."

Beast Within

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

Ochre Jelly

Trample
Ochre Jelly enters the battlefield with X +1/+1 counters on it.
Split — When Ochre Jelly dies, if it had two or more +1/+1 counters on it, create a token that's a copy of it at the beginning of the next end step. The token enters the battlefield with half that many +1/+1 counters on it, rounded down.

Shamanic Revelation

Draw a card for each creature you control.
Ferocious — You gain 4 life for each creature you control with power 4 or greater.

Tuskguard Captain

Outlast {G} ({G}, {T}: Put a +1/+1 counter on this creature. Outlast only as a sorcery.)
Each creature you control with a +1/+1 counter on it has trample.

Biogenic Ooze

When Biogenic Ooze enters the battlefield, create a 2/2 green Ooze creature token.
At the beginning of your end step, put a +1/+1 counter on each Ooze you control.
{1}{G}{G}{G}: Create a 2/2 green Ooze creature token.

Slime Molding

Biogenic Upgrade

Distribute three +1/+1 counters among one, two, or three target creatures, then double the number of +1/+1 counters on each of those creatures.

Forest

Chameleon Colossus

Changeling (This card is every creature type.)
Protection from black
{2}{G}{G}: Chameleon Colossus gets +X/+X until end of turn, where X is its power.

Manaplasm

Whenever you cast a spell, Manaplasm gets +X/+X until end of turn, where X is that spell's mana value.

Song of Freyalise

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I, II — Until your next turn, creatures you control gain "{T}: Add one mana of any color."
III — Put a +1/+1 counter on each creature you control. Those creatures gain vigilance, trample, and indestructible until end of turn.

Predator Ooze

Indestructible
Whenever Predator Ooze attacks, put a +1/+1 counter on it.
Whenever a creature dealt damage by Predator Ooze this turn dies, put a +1/+1 counter on Predator Ooze.

Mwonvuli Ooze

Cumulative upkeep {2} (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay {2} for each age counter on it.)
Mwonvuli Ooze's power and toughness are each equal to 1 plus twice the number of age counters on it.

Mycoloth

Devour 2 (As this enters the battlefield, you may sacrifice any number of creatures. This creature enters the battlefield with twice that many +1/+1 counters on it.)
At the beginning of your upkeep, create a 1/1 green Saproling creature token for each +1/+1 counter on Mycoloth.

Ooze Garden

{1}{G}, Sacrifice a non-Ooze creature: Create an X/X green Ooze creature token, where X is the sacrificed creature's power. Activate only as a sorcery.

Coat of Arms

Each creature gets +1/+1 for each other creature on the battlefield that shares at least one creature type with it. (For example, if two Goblin Warriors and a Goblin Shaman are on the battlefield, each gets +2/+2.)

Ancient Ooze

Ancient Ooze's power and toughness are each equal to the total mana value of other creatures you control.

Courage in Crisis

Put a +1/+1 counter on target creature, then proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Increasing Savagery

Put five +1/+1 counters on target creature. If this spell was cast from a graveyard, put ten +1/+1 counters on that creature instead.
Flashback {5}{G}{G} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Branching Evolution

If one or more +1/+1 counters would be put on a creature you control, twice that many +1/+1 counters are put on that creature instead.

Ooze Flux

{1}{G}, Remove one or more +1/+1 counters from among creatures you control: Create an X/X green Ooze creature token, where X is the number of +1/+1 counters removed this way.

Prey Upon

Target creature you control fights target creature you don't control. (Each deals damage equal to its power to the other.)

Castle Garenbrig

Castle Garenbrig enters the battlefield tapped unless you control a Forest.
{T}: Add {G}.
{2}{G}{G}, {T}: Add six {G}. Spend this mana only to cast creature spells or activate abilities of creatures.

Hunter's Edge

Put a +1/+1 counter on target creature you control. Then that creature deals damage equal to its power to target creature you don't control.

Arbor Armament

Put a +1/+1 counter on target creature. That creature gains reach until end of turn.

Snakeskin Veil

Put a +1/+1 counter on target creature you control. It gains hexproof until end of turn. (It can't be the target of spells or abilities your opponents control.)

Miming Slime

Create an X/X green Ooze creature token, where X is the greatest power among creatures you control.

Vastwood Surge

Kicker {4} (You may pay an additional {4} as you cast this spell.)
Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle. If this spell was kicked, put two +1/+1 counters on each creature you control.

Strength of the Tajuru

Multikicker {1} (You may pay an additional {1} any number of times as you cast this spell.)
Choose target creature, then choose another target creature for each time this spell was kicked. Put X +1/+1 counters on each of them.

Vastwood Thicket

Vastwood Thicket enters the battlefield tapped.
{T}: Add {G}.

Vastwood Fortification

Vastwood Fortification // Vastwood Thicket

The Ozolith

Whenever a creature you control leaves the battlefield, if it had counters on it, put those counters on The Ozolith.
At the beginning of combat on your turn, if The Ozolith has counters on it, you may move all counters from The Ozolith onto target creature.

Guardian Project

Whenever a nontoken creature enters the battlefield under your control, if it doesn't have the same name as another creature you control or a creature card in your graveyard, draw a card.

Slurrk, All-Ingesting

Slurrk, All-Ingesting enters the battlefield with five +1/+1 counters on it.
Whenever Slurrk or another creature you control dies, if it had a +1/+1 counter on it, put a +1/+1 counter on each creature you control that has a +1/+1 counter on it.
Partner (You can have two commanders if both have partner.)

Gutter Grime

Whenever a nontoken creature you control dies, put a slime counter on Gutter Grime, then create a green Ooze creature token with "This creature's power and toughness are each equal to the number of slime counters on Gutter Grime."

Realmwalker

Changeling (This card is every creature type.)
As Realmwalker enters the battlefield, choose a creature type.
You may look at the top card of your library any time.
You may cast creature spells of the chosen type from the top of your library.

Kudzu

Enchant land
When enchanted land becomes tapped, destroy it. That land's controller may attach Kudzu to a land of their choice.

Acidic Slime

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
When Acidic Slime enters the battlefield, destroy target artifact, enchantment, or land.

Beast Whisperer

Whenever you cast a creature spell, draw a card.

Titanic Brawl

This spell costs {1} less to cast if it targets a creature you control with a +1/+1 counter on it.
Target creature you control fights target creature you don't control. (Each deals damage equal to its power to the other.)

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.)

Oran-Rief Ooze

When Oran-Rief Ooze enters the battlefield, put a +1/+1 counter on target creature you control.
Whenever Oran-Rief Ooze attacks, put a +1/+1 counter on each attacking creature with a +1/+1 counter on it.

Evolution Sage

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

Vanquisher's Banner

As Vanquisher's Banner enters the battlefield, choose a creature type.
Creatures you control of the chosen type get +1/+1.
Whenever you cast a creature spell of the chosen type, draw a card.

Stony Strength

Put a +1/+1 counter on target creature you control. Untap that creature.

Garruk, Primal Hunter

+1: Create a 3/3 green Beast creature token.
−3: Draw cards equal to the greatest power among creatures you control.
−6: Create a 6/6 green Wurm creature token for each land you control.

Riptide Replicator

As Riptide Replicator enters the battlefield, choose a color and a creature type.
Riptide Replicator enters the battlefield with X charge counters on it.
{4}, {T}: Create an X/X creature token of the chosen color and type, where X is the number of charge counters on Riptide Replicator.

Ravenous Slime

Ravenous Slime can't be blocked by creatures with power 2 or less.
If a creature an opponent controls would die, instead exile it and put a number of +1/+1 counters equal to that creature's power on Ravenous Slime.