Pir, Imaginative Rascal

Partner with Toothy, Imaginary Friend (When this creature enters, 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.

Phantom Wurm

Phantom Wurm enters with four +1/+1 counters on it.
If damage would be dealt to Phantom Wurm, prevent that damage. Remove a +1/+1 counter from Phantom Wurm.

Omnibian

{T}: Target creature becomes a Frog with base power and toughness 3/3 until end of turn.

Biovisionary

At the beginning of the end step, if you control four or more creatures named Biovisionary, you win the game.

Mirror Image

You may have Mirror Image enter as a copy of a creature you control.

Vorel of the Hull Clade

{G}{U}, {T}: Double the number of each kind of counter on target artifact, creature, or land.

Drakewing Krasis

Believe

Aftermath (Cast this spell only from your graveyard. Then exile it.)
Look at the top card of your library. You may put it onto the battlefield if it's a creature card. If you don't, put it into your hand.

Reason

Reason // Believe

Sagu Mauler

Trample, hexproof
Morph {3}{G}{U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Prime Speaker Zegana

Prime Speaker Zegana enters with X +1/+1 counters on it, where X is the greatest power among other creatures you control.
When Prime Speaker Zegana enters, draw cards equal to its power.

Forced Adaptation

Enchant creature
At the beginning of your upkeep, put a +1/+1 counter on enchanted creature.

Sylvan Caryatid

Defender, hexproof
{T}: Add one mana of any color.

Fated Infatuation

Create a token that's a copy of target creature you control. If it's your turn, scry 2.

Counterspell

Shielding Plax

({G/U} can be paid with either {G} or {U}.)
Enchant creature
When Shielding Plax enters, draw a card.
Enchanted creature can't be the target of spells or abilities your opponents control.

Rite of Replication

Kicker {5} (You may pay an additional {5} as you cast this spell.)
Create a token that's a copy of target creature. If this spell was kicked, create five of those tokens instead.

Solidarity of Heroes

Strive — This spell costs {1}{G} more to cast for each target beyond the first.
Choose any number of target creatures. Double the number of +1/+1 counters on each of them.

Prismatic Lens

{T}: Add {C}.
{1}, {T}: Add one mana of any color.

Woodland Stream

Woodland Stream enters tapped.
{T}: Add {G} or {U}.

Supplant Form

Return target creature to its owner's hand. You create a token that's a copy of that creature.

Unknown Shores

Crystalline Crawler

Converge — Crystalline Crawler enters with a +1/+1 counter on it for each color of mana spent to cast it.
Remove a +1/+1 counter from Crystalline Crawler: Add one mana of any color.
{T}: Put a +1/+1 counter on Crystalline Crawler.

Bounding Krasis

Flash (You may cast this spell any time you could cast an instant.)
When Bounding Krasis enters, you may tap or untap target creature.

Lorescale Coatl

Whenever you draw a card, put a +1/+1 counter on Lorescale Coatl.

Chasm Skulker

Whenever you draw a card, put a +1/+1 counter on Chasm Skulker.
When Chasm Skulker dies, create X 1/1 blue Squid creature tokens with islandwalk, where X is the number of +1/+1 counters on Chasm Skulker. (They can't be blocked as long as defending player controls an Island.)

Simic Cluestone

{T}: Add {G} or {U}.
{G}{U}, {T}, Sacrifice Simic Cluestone: Draw a card.

Thrive

Put a +1/+1 counter on each of X target creatures.

Saheeli's Artistry

Choose one or both —
• Create a token that's a copy of target artifact.
• Create a token that's a copy of target creature, except it's an artifact in addition to its other types.

Gyre Sage

Evolve (Whenever a creature you control enters, if that creature has greater power or toughness than this creature, put a +1/+1 counter on this creature.)
{T}: Add {G} for each +1/+1 counter on Gyre Sage.

Minds Aglow

Join forces — Starting with you, each player may pay any amount of mana. Each player draws X cards, where X is the total amount of mana paid this way.

Galloping Lizrog

Trample
When Galloping Lizrog enters, you may remove any number of +1/+1 counters from among creatures you control. If you do, put twice that many +1/+1 counters on Galloping Lizrog.

Spitting Image

Create a token that's a copy of target creature.
Retrace (You may cast this card from your graveyard by discarding a land card in addition to paying its other costs.)

Pir's Whim

For each player, choose friend or foe. Each friend searches their library for a land card, puts it onto the battlefield tapped, then shuffles. Each foe sacrifices an artifact or enchantment of their choice.

Fuel for the Cause

Counter target spell, then proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Master Biomancer

Each other creature you control enters with a number of additional +1/+1 counters on it equal to Master Biomancer's power and as a Mutant in addition to its other types.

Steady Progress

Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)
Draw a card.

Bring to Light

Converge — Search your library for a creature, instant, or sorcery card with mana value less than or equal to the number of colors of mana spent to cast this spell, exile that card, then shuffle. You may cast that card without paying its mana cost.

Snakeform

Until end of turn, target creature loses all abilities and becomes a green Snake with base power and toughness 1/1.
Draw a card.

Cauldron of Souls

{T}: Choose any number of target creatures. Each of those creatures gains persist until end of turn. (When it dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Arixmethes, Slumbering Isle

Arixmethes, Slumbering Isle enters tapped with five slumber counters on it.
As long as Arixmethes has a slumber counter on it, it's a land. (It's not a creature.)
Whenever you cast a spell, you may remove a slumber counter from Arixmethes.
{T}: Add {G}{U}.

Thought Vessel

You have no maximum hand size.
{T}: Add {C}.

Biomancer's Familiar

Activated abilities of creatures you control cost {2} less to activate. This effect can't reduce the mana in that cost to less than one mana.
{T}: The next time target creature adapts this turn, it adapts as though it had no +1/+1 counters on it.

Rogue's Passage

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

Helm of the Host

At the beginning of combat on your turn, create a token that's a copy of equipped creature, except the token isn't legendary. That token gains haste.
Equip {5}

Progenitor Mimic

You may have Progenitor Mimic enter as a copy of any creature on the battlefield, except it has "At the beginning of your upkeep, if this creature isn't a token, create a token that's a copy of this creature."

Crypsis

Target creature you control gains protection from creatures your opponents control until end of turn. Untap it.

Guardian Project

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

Replicate

Create a token that's a copy of target creature you control.

Repudiate

Counter target activated or triggered ability. (Mana abilities can't be targeted.)

Repudiate // Replicate

Zegana, Utopian Speaker

When Zegana, Utopian Speaker enters, if you control another creature with a +1/+1 counter on it, draw a card.
{4}{G}{U}: Adapt 4. (If this creature has no +1/+1 counters on it, put four +1/+1 counters on it.)
Each creature you control with a +1/+1 counter on it has trample.

Kiora, the Crashing Wave

+1: Until your next turn, prevent all damage that would be dealt to and dealt by target permanent an opponent controls.
−1: Draw a card. You may play an additional land this turn.
−5: You get an emblem with "At the beginning of your end step, create a 9/9 blue Kraken creature token."

Opal Palace

{T}: Add {C}.
{1}, {T}: Add one mana of any color in your commander's color identity. If you spend this mana to cast your commander, it enters with a number of additional +1/+1 counters on it equal to the number of times it's been cast from the command zone this game.

Benthic Biomancer

{1}{U}: Adapt 1. (If this creature has no +1/+1 counters on it, put a +1/+1 counter on it.)
Whenever one or more +1/+1 counters are put on Benthic Biomancer, draw a card, then discard a card.

Invisibility

Enchant creature
Enchanted creature can't be blocked except by Walls.

Wilderness Reclamation

At the beginning of your end step, untap all lands you control.

Simic Growth Chamber

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

Spark Double

You may have Spark Double enter as a copy of a creature or planeswalker you control, except it enters with an additional +1/+1 counter on it if it's a creature, it enters with an additional loyalty counter on it if it's a planeswalker, and it isn't legendary.

Unravel the Aether

Choose target artifact or enchantment. Its owner shuffles it into their library.

Reliquary Tower

Bioshift

Move any number of +1/+1 counters from target creature onto another target creature with the same controller.

Mistcutter Hydra

This spell can't be countered.
Haste, protection from blue
Mistcutter Hydra enters with X +1/+1 counters on it.

Plaxcaster Frogling

Graft 3 (This creature enters with three +1/+1 counters on it. Whenever another creature enters, you may move a +1/+1 counter from this creature onto it.)
{2}: Target creature with a +1/+1 counter on it gains shroud until end of turn. (It can't be the target of spells or abilities.)

Merfolk Branchwalker

When Merfolk Branchwalker enters, 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 this creature, then put the card back or put it into your graveyard.)

Tishana, Voice of Thunder

Tishana, Voice of Thunder's power and toughness are each equal to the number of cards in your hand.
You have no maximum hand size.
When Tishana enters, draw a card for each creature you control.

Body Double

You may have Body Double enter as a copy of any creature card in a graveyard.

Prey Upon

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

Cancel

Open into Wonder

X target creatures can't be blocked this turn. Until end of turn, those creatures gain "Whenever this creature deals combat damage to a player, draw a card."

Glen Elendra Archmage

Flying
{U}, Sacrifice Glen Elendra Archmage: Counter target noncreature spell.
Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Cytoshape

Choose a nonlegendary creature on the battlefield. Target creature becomes a copy of that creature until end of turn.

Horizon Chimera

Flash
Flying, trample
Whenever you draw a card, you gain 1 life.

Merfolk Looter

Kiora's Follower

Biomantic Mastery

Draw a card for each creature target player controls, then draw a card for each creature another target player controls.

Hydroid Krasis

When you cast this spell, you gain half X life and draw half X cards. Round down each time.
Flying, trample
Hydroid Krasis enters with X +1/+1 counters on it.

Forest

Toothy, Imaginary Friend

Partner with Pir, Imaginative Rascal (When this creature enters, target player may put Pir into their hand from their library, then shuffle.)
Whenever you draw a card, put a +1/+1 counter on Toothy, Imaginary Friend.
When Toothy leaves the battlefield, draw a card for each +1/+1 counter on it.

Unclaimed Territory

As Unclaimed Territory enters, choose a creature type.
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type.

Spellbook

Renegade Krasis

Evolve (Whenever a creature you control enters, if that creature has greater power or toughness than this creature, put a +1/+1 counter on this creature.)
Whenever Renegade Krasis evolves, put a +1/+1 counter on each other creature you control with a +1/+1 counter on it.

Skyrider Patrol

Flying
At the beginning of combat on your turn, you may pay {G}{U}. When you do, put a +1/+1 counter on another target creature you control, and that creature gains flying until end of turn.

Bred for the Hunt

Whenever a creature you control with a +1/+1 counter on it deals combat damage to a player, you may draw a card.

Shimmering Grotto

Tatyova, Benthic Druid

Landfall — Whenever a land you control enters, you gain 1 life and draw a card.

Zameck Guildmage

{G}{U}: This turn, each creature you control enters with an additional +1/+1 counter on it.
{G}{U}, Remove a +1/+1 counter from a creature you control: Draw a card.

Simic Ascendancy

{1}{G}{U}: Put a +1/+1 counter on target creature you control.
Whenever one or more +1/+1 counters are put on a creature you control, put that many growth counters on Simic Ascendancy.
At the beginning of your upkeep, if Simic Ascendancy has twenty or more growth counters on it, you win the game.