Counterspell

Evolving Wilds

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

Command Tower

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

Wilderness Reclamation

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

Lush Oasis

Lush Oasis enters the battlefield tapped.
When Lush Oasis enters the battlefield, it deals 1 damage to target opponent.
{T}: Add {G} or {U}.

Spelunking

When Spelunking enters the battlefield, draw a card, then you may put a land card from your hand onto the battlefield. If you put a Cave onto the battlefield this way, you gain 4 life.
Lands you control enter the battlefield untapped.

Island

Voidslime

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

Venser, Shaper Savant

Flash
When Venser, Shaper Savant enters the battlefield, return target spell or permanent to its owner's hand.

Draining Whelk

Flash
Flying
When Draining Whelk enters the battlefield, counter target spell. Put X +1/+1 counters on Draining Whelk, where X is that spell's mana value.

Rampant Growth

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Merfolk Trickster

Flash
When Merfolk Trickster enters the battlefield, tap target creature an opponent controls. It loses all abilities until end of turn.

Thriving Grove

Thriving Grove enters the battlefield tapped.
As Thriving Grove enters the battlefield, choose a color other than green.
{T}: Add {G} or one mana of the chosen color.

Woodland Stream

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

Hinterland Harbor

Hinterland Harbor enters the battlefield tapped unless you control a Forest or an Island.
{T}: Add {G} or {U}.

Malleable Impostor

Flash
Flying
You may have Malleable Impostor enter the battlefield as a copy of a creature an opponent controls, except it's a Faerie Shapeshifter in addition to its other types and it has flying.

Consider

Surveil 1. (Look at the top card of your library. You may put it into your graveyard.)
Draw a card.

Terramorphic Expanse

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

Frantic Search

Draw two cards, then discard two cards. Untap up to three lands.

Mystic Snake

Flash
When Mystic Snake enters the battlefield, counter target spell.

Future Sight

Play with the top card of your library revealed.
You may play lands and cast spells from the top of your library.

Stunt Double

Flash
You may have Stunt Double enter the battlefield as a copy of any creature on the battlefield.

Lonely Sandbar

Lonely Sandbar enters the battlefield tapped.
{T}: Add {U}.
Cycling {U} ({U}, Discard this card: Draw a card.)

Thought Vessel

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

Joint Exploration

Kicker {G} (You may pay an additional {G} as you cast this spell.)
Scry 2, then draw a card. If this spell was kicked, you may put a land card from your hand onto the battlefield.

Misleading Signpost

Flash
When Misleading Signpost enters the battlefield during the declare attackers step, you may reselect which player or permanent target attacking creature is attacking. (It can't attack its controller or their permanents.)
{T}: Add {U}.

Portal Mage

Flash
When Portal Mage enters the battlefield during the declare attackers step, you may reselect which player or permanent target attacking creature is attacking. (It can't attack its controller or its controller's planeswalkers.)

Rewind

Counter target spell. Untap up to four lands.

Deep Analysis

Target player draws two cards.
Flashback—{1}{U}, Pay 3 life. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Thriving Isle

Thriving Isle enters the battlefield tapped.
As Thriving Isle enters the battlefield, choose a color other than blue.
{T}: Add {U} or one mana of the chosen color.

Wildborn Preserver

Flash
Reach
Whenever another non-Human creature enters the battlefield under your control, you may pay {X}. When you do, put X +1/+1 counters on Wildborn Preserver.

Forest

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.

Aboleth Spawn

Flash
Ward {2}
Probing Telepathy — Whenever a creature entering the battlefield under an opponent's control causes a triggered ability of that creature to trigger, you may copy that ability. You may choose new targets for the copy.

Unwind

Counter target noncreature spell. Untap up to three lands.

Arcane Signet

Hullbreaker Horror

Flash
This spell can't be countered.
Whenever you cast a spell, choose up to one —
• Return target spell you don't control to its owner's hand.
• Return target nonland permanent to its owner's hand.

Cultivate

Snap

Return target creature to its owner's hand. Untap up to two lands.

Propaganda

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

Sapphire Medallion

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

Preordain

Scry 2, then draw a card. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Ponder

Look at the top three cards of your library, then put them back in any order. You may shuffle.
Draw a card.

Nightpack Ambusher

Flash
Other Wolves and Werewolves you control get +1/+1.
At the beginning of your end step, if you didn't cast a spell this turn, create a 2/2 green Wolf creature token.

Brineborn Cutthroat

Flash (You may cast this spell any time you could cast an instant.)
Whenever you cast a spell during an opponent's turn, put a +1/+1 counter on Brineborn Cutthroat.

Ash Barrens

{T}: Add {C}.
Basic landcycling {1} ({1}, Discard this card: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.)

Mana Leak

Counter target spell unless its controller pays {3}.

Temple of Mystery

Temple of Mystery enters the battlefield tapped.
When Temple of Mystery enters the battlefield, scry 1.
{T}: Add {G} or {U}.

Voracious Greatshark

Flash
When Voracious Greatshark enters the battlefield, counter target artifact or creature spell.

Fierce Guardianship

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

Brainsurge

Draw four cards, then put two cards from your hand on top of your library in any order.

Bounding Krasis

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

As Foretold

At the beginning of your upkeep, put a time counter on As Foretold.
Once each turn, you may pay {0} rather than pay the mana cost for a spell you cast with mana value X or less, where X is the number of time counters on As Foretold.

Seedborn Muse

Untap all permanents you control during each other player's untap step.

Mindsplice Apparatus

Flash
At the beginning of your upkeep, put an oil counter on Mindsplice Apparatus.
Instant and sorcery spells you cast cost {1} less to cast for each oil counter on Mindsplice Apparatus.

Talisman of Curiosity

{T}: Add {C}.
{T}: Add {G} or {U}. Talisman of Curiosity deals 1 damage to you.

Tranquil Thicket

Tranquil Thicket enters the battlefield tapped.
{T}: Add {G}.
Cycling {G} ({G}, Discard this card: Draw a card.)

Naiad of Hidden Coves

As long as it's not your turn, spells you cast cost {1} less to cast.

Exclude

Counter target creature spell.
Draw a card.

Dragon Turtle

Flash
Drag Below — When Dragon Turtle enters the battlefield, tap it and up to one target creature an opponent controls. They don't untap during their controllers' next untap steps.

Frilled Mystic

Flash
When Frilled Mystic enters the battlefield, you may counter target spell.

Aetherize

Return all attacking creatures to their owner's hand.

Teferi, Mage of Zhalfir

Flash
Creature cards you own that aren't on the battlefield have flash.
Each opponent can cast spells only any time they could cast a sorcery.

Growth Spiral

Draw a card. You may put a land card from your hand onto the battlefield.

Thornwood Falls

Thornwood Falls enters the battlefield tapped.
When Thornwood Falls enters the battlefield, you gain 1 life.
{T}: Add {G} or {U}.

Leyline of Anticipation

If Leyline of Anticipation is in your opening hand, you may begin the game with it on the battlefield.
You may cast spells as though they had flash.

Brainstorm

Draw three cards, then put two cards from your hand on top of your library in any order.

Jin-Gitaxias, Core Augur

Flash
At the beginning of your end step, draw seven cards.
Each opponent's maximum hand size is reduced by seven.

Yavimaya Coast

{T}: Add {C}.
{T}: Add {G} or {U}. Yavimaya Coast deals 1 damage to you.

Reliquary Tower

Emerald Medallion

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

Wavebreak Hippocamp

Whenever you cast your first spell during each opponent's turn, draw a card.

Plaxmanta

Flash
When Plaxmanta enters the battlefield, creatures you control gain shroud until end of turn. (They can't be the targets of spells or abilities.)
When Plaxmanta enters the battlefield, sacrifice it unless {G} was spent to cast it.

Reclaim

Put target card from your graveyard on top of your library.

Aether Gale

Return six target nonland permanents to their owners' hands.

Sol Ring

Torrential Gearhulk

Flash
When Torrential Gearhulk enters the battlefield, you may cast target instant card from your graveyard without paying its mana cost. If that spell would be put into your graveyard, exile it instead.

Arachnogenesis

Create X 1/2 green Spider creature tokens with reach, where X is the number of creatures attacking you. Prevent all combat damage that would be dealt this turn by non-Spider creatures.

Eureka Moment

Draw two cards. You may put a land card from your hand onto the battlefield.

Spectral Sailor

Flash (You may cast this spell any time you could cast an instant.)
Flying
{3}{U}: Draw a card.

Simic Guildgate

Simic Guildgate enters the battlefield tapped.
{T}: Add {G} or {U}.

Rashmi, Eternities Crafter

Whenever you cast your first spell each turn, reveal the top card of your library. You may cast it without paying its mana cost if it's a spell with lesser mana value. If you don't cast it, put it into your hand.

Halimar Depths

Halimar Depths enters the battlefield tapped.
When Halimar Depths enters the battlefield, look at the top three cards of your library, then put them back in any order.
{T}: Add {U}.