Maybe

Perplexing Test

Choose one —
• Return all creature tokens to their owners' hands.
• Return all nontoken creatures to their owners' hands.

Cutting

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 this enchantment.
At the beginning of your upkeep, if this enchantment has twenty or more growth counters on it, you win the game.

Have

Arcane Signet

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

Loran of the Third Path

Vigilance
When Loran enters, destroy up to one target artifact or enchantment.
{T}: You and target opponent each draw a card.

Thriving Heath

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

Glacial Fortress

This land enters tapped unless you control a Plains or an Island.
{T}: Add {W} or {U}.

Temple of Plenty

This land enters tapped.
When this land enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)
{T}: Add {G} or {W}.

Jolly Gerbils

Baird, Steward of Argive

Vigilance
Creatures can't attack you or planeswalkers you control unless their controller pays {1} for each of those creatures.

Bloodroot Apothecary

Toxic 2 (Players dealt combat damage by this creature also get two poison counters. A player with ten or more poison counters loses the game.)
When this creature enters, you and target opponent each create a Treasure token.
Whenever an opponent sacrifices a noncreature token, that player gets two poison counters.

Farseek

Search your library for a Plains, Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle.

Ms. Bumbleflower

Vigilance
Whenever you cast a spell, target opponent draws a card. Put a +1/+1 counter on target creature. It gains flying until end of turn. If this is the second time this ability has resolved this turn, you draw two cards.

Octomancer

Gift an Octopus (You may promise an opponent a gift as you cast this spell. If you do, when it enters, they create an 8/8 blue Octopus creature token.)
At the beginning of each end step, create a token that's a copy of target creature token that entered the battlefield this turn.

Mr. Foxglove

Lifelink
Whenever Mr. Foxglove attacks, draw cards equal to the number of cards in defending player's hand minus the number of cards in your hand. If you didn't draw cards this way, you may put a creature card from your hand onto the battlefield.

Tamiyo, Field Researcher

+1: Choose up to two target creatures. Until your next turn, whenever either of those creatures deals combat damage, you draw a card.
−2: Tap up to two target nonland permanents. They don't untap during their controller's next untap step.
−7: Draw three cards. You get an emblem with "You may cast spells from your hand without paying their mana costs."

Cultivate

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.

Faeburrow Elder

Vigilance
This creature gets +1/+1 for each color among permanents you control.
{T}: For each color among permanents you control, add one mana of that color.

Adarkar Wastes

{T}: Add {C}.
{T}: Add {W} or {U}. This land deals 1 damage to you.

Jolrael, Mwonvuli Recluse

Whenever you draw your second card each turn, create a 2/2 green Cat creature token.
{4}{G}{G}: Until end of turn, creatures you control have base power and toughness X/X, where X is the number of cards in your hand.

Prairie Stream

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

Spore Frog

Sacrifice this creature: Prevent all combat damage that would be dealt this turn.

Sunpetal Grove

This land enters tapped unless you control a Forest or a Plains.
{T}: Add {G} or {W}.

Kalonian Hydra

Trample
This creature enters with four +1/+1 counters on it.
Whenever this creature attacks, double the number of +1/+1 counters on each creature you control.

Forgotten Ancient

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

Temple of Mystery

This land enters tapped.
When this land enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)
{T}: Add {G} or {U}.

Martial Impetus

Enchant creature
Enchanted creature gets +1/+1 and is goaded. (It attacks each combat if able and attacks a player other than you if able.)
Whenever enchanted creature attacks, each other creature that's attacking one of your opponents gets +1/+1 until end of turn.

Managorger Hydra

Trample
Whenever a player casts a spell, put a +1/+1 counter on this creature.

Forest

Coveted Jewel

When this artifact enters, draw three cards.
{T}: Add three mana of any one color.
Whenever one or more creatures an opponent controls attack you and aren't blocked, that player draws three cards and gains control of this artifact. Untap it.

Chasm Skulker

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

Exotic Orchard

{T}: Add one mana of any color that a land an opponent controls could produce.

Secret Rendezvous

You and target opponent each draw three cards.

Reliquary Tower

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

Steelburr Champion

Offspring {1}{W} (You may pay an additional {1}{W} as you cast this spell. If you do, when this creature enters, create a 1/1 token copy of it.)
Vigilance
Whenever an opponent casts a noncreature spell, put a +1/+1 counter on this creature.

Triskaidekaphile

You have no maximum hand size.
At the beginning of your upkeep, if you have exactly thirteen cards in your hand, you win the game.
{3}{U}: Draw a card.

Fellwar Stone

Wizard Class

(Gain the next level as a sorcery to add its ability.)
You have no maximum hand size.
{2}{U}: Level 2
When this Class becomes level 2, draw two cards.
{4}{U}: Level 3
Whenever you draw a card, put a +1/+1 counter on target creature you control.

Island

Hinterland Harbor

This land enters tapped unless you control a Forest or an Island.
{T}: Add {G} or {U}.

Sphinx of Enlightenment

Flying
When this creature enters, target opponent draws a card and you draw three cards.

Generous Gift

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

An Offer You Can't Refuse

Counter target noncreature spell. Its controller creates two Treasure tokens. (They're artifacts with "{T}, Sacrifice this token: Add one mana of any color.")

Communal Brewing

When this enchantment enters, any number of target opponents each draw a card. Put an ingredient counter on this enchantment, then put an ingredient counter on it for each card drawn this way.
Whenever you cast a creature spell, that creature enters with X additional +1/+1 counters on it, where X is the number of ingredient counters on this enchantment.

Coiling Oracle

When this creature enters, reveal the top card of your library. If it's a land card, put it onto the battlefield. Otherwise, put that card into your hand.

Sol Ring

Hoofprints of the Stag

Whenever you draw a card, you may put a hoofprint counter on this enchantment.
{2}{W}, Remove four hoofprint counters from this enchantment: Create a 4/4 white Elemental creature token with flying. Activate only during your turn.

Fisher's Talent

(Gain the next level as a sorcery to add its ability.)
At the beginning of your upkeep, look at the top card of your library. You may reveal it if it's a land card. Create a 1/1 blue Fish creature token if you revealed it this way. Then draw a card.
{G}{U}: Level 2
If you would create a Fish token, create a 3/3 blue Shark creature token instead.
{2}{G}{U}: Level 3
If you would create a Shark token, create an 8/8 blue Octopus creature token instead.

Plains

Promise of Loyalty

Each player puts a vow counter on a creature they control and sacrifices the rest. Each of those creatures can't attack you or planeswalkers you control for as long as it has a vow counter on it.

Razorverge Thicket

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

Tempt with Bunnies

Tempting Offer — Draw a card and create a 1/1 white Rabbit creature token. Then each opponent may draw a card and create a 1/1 white Rabbit creature token. For each opponent who does, you draw a card and you create a 1/1 white Rabbit creature token.

Long River's Pull

Gift a card (You may promise an opponent a gift as you cast this spell. If you do, they draw a card before its other effects.)
Counter target creature spell. If the gift was promised, instead counter target spell.

Flooded Grove

{T}: Add {C}.
{G/U}, {T}: Add {G}{G}, {G}{U}, or {U}{U}.

Skycloud Expanse

Riot Control

You gain 1 life for each creature your opponents control. Prevent all damage that would be dealt to you this turn.

Mangara, the Diplomat

Lifelink
Whenever an opponent attacks with creatures, if two or more of those creatures are attacking you and/or planeswalkers you control, draw a card.
Whenever an opponent casts their second spell each turn, draw a card.

Selvala, Explorer Returned

Parley — {T}: Each player reveals the top card of their library. For each nonland card revealed this way, add {G} and you gain 1 life. Then each player draws a card.

Sungrass Prairie

Evolving Wilds

{T}, Sacrifice this land: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Rishkar, Peema Renegade

When Rishkar enters, 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}."

Tempt with Discovery

Tempting offer — Search your library for a land card and put it onto the battlefield. Each opponent may search their library for a land card and put it onto the battlefield. For each opponent who searches a library this way, search your library for a land card and put it onto the battlefield. Then each player who searched a library this way shuffles.

Canopy Vista

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

Sunscorch Regent

Flying
Whenever an opponent casts a spell, put a +1/+1 counter on this creature and you gain 1 life.

Command Tower

Illusionist's Gambit

Cast this spell only during the declare blockers step on an opponent's turn.
Remove all attacking creatures from combat and untap them. After this phase, there is an additional combat phase. Each of those creatures attacks that combat if able. They can't attack you or planeswalkers you control that combat.

Rites of Flourishing

At the beginning of each player's draw step, that player draws an additional card.
Each player may play an additional land on each of their turns.

Ghirapur Orrery

Each player may play an additional land on each of their turns.
At the beginning of each player's upkeep, if that player has no cards in hand, that player draws three cards.

Psychosis Crawler

Psychosis Crawler's power and toughness are each equal to the number of cards in your hand.
Whenever you draw a card, each opponent loses 1 life.

Body of Knowledge

Body of Knowledge's power and toughness are each equal to the number of cards in your hand.
You have no maximum hand size.
Whenever this creature is dealt damage, draw that many cards.

Temple of Enlightenment

This land enters tapped.
When this land enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)
{T}: Add {W} or {U}.

Peerless Recycling

Gift a card (You may promise an opponent a gift as you cast this spell. If you do, they draw a card before its other effects.)
Return target permanent card from your graveyard to your hand. If the gift was promised, instead return two target permanent cards from your graveyard to your hand.

Seaside Citadel

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

Overflowing Basin

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.

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.

Twenty-Toed Toad

Your maximum hand size is twenty.
Whenever you attack with two or more creatures, put a +1/+1 counter on this creature and draw a card.
Whenever this creature attacks, you win the game if there are twenty or more counters on it or you have twenty or more cards in hand.

Cast Off

Destroy all non-Giant creatures. (Then exile this card. You may cast the creature later from exile.)

Realm-Cloaked Giant

Realm-Cloaked Giant // Cast Off

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control. It can attack and {T} no matter when it came under your control.)
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Terramorphic Expanse

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

Perch Protection

Gift an extra turn (You may promise an opponent a gift as you cast this spell. If you do, they take an extra turn after this one.)
Create four 2/2 blue Bird creature tokens with flying. If the gift was promised, all permanents you control phase out, and until your next turn, your life total can't change and you gain protection from everything.
Exile Perch Protection.

Broken Wings

Destroy target artifact, enchantment, or creature with flying.

Tenuous Truce

Enchant opponent
At the beginning of enchanted opponent's end step, you and that player each draw a card.
When you attack enchanted opponent or a planeswalker they control or when they attack you or a planeswalker you control, sacrifice this Aura.

Yavimaya Coast

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

Intellectual Offering

Choose an opponent. You and that player each draw three cards.
Choose an opponent. Untap all nonland permanents you control and all nonland permanents that player controls.

Thought Vessel

Kwain, Itinerant Meddler

{T}: Each player may draw a card, then each player who drew a card this way gains 1 life.

Seachrome Coast

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

Wear Down

Gift a card (You may promise an opponent a gift as you cast this spell. If you do, they draw a card before its other effects.)
Destroy target artifact or enchantment. If the gift was promised, instead destroy two target artifacts and/or enchantments.