Misleading Signpost

Flash
When this artifact enters 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}.

Island

Sigarda's Vanguard

Flash
Flying
Whenever this creature enters or attacks, choose any number of creatures with different powers. Those creatures gain double strike until end of turn.

Fear of Impostors

Flash
When this creature enters, counter target spell. Its controller manifests dread. (That player looks at the top two cards of their library, then puts one onto the battlefield face down as a 2/2 creature and the other into their graveyard. If it's a creature card, it can be turned face up any time for its mana cost.)

Angel of the Dire Hour

Flash
Flying
When this creature enters, if you cast it from your hand, exile all attacking creatures.

Dream Eater

Flash
Flying
When this creature enters, surveil 4. When you do, you may return target nonland permanent an opponent controls to its owner's hand. (To surveil 4, look at the top four cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)

Leyline of Anticipation

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

Restoration Angel

Flash
Flying
When this creature enters, you may exile target non-Angel creature you control, then return that card to the battlefield under your control.

Sol Ring

Cathar Commando

Flash
{1}, Sacrifice this creature: Destroy target artifact or enchantment.

Glorious Protector

Flash
Flying
When this creature enters, you may exile any number of non-Angel creatures you control until this creature leaves the battlefield.
Foretell {2}{W}

Celestial Colonnade

This land enters tapped.
{T}: Add {W} or {U}.
{3}{W}{U}: Until end of turn, this land becomes a 4/4 white and blue Elemental creature with flying and vigilance. It's still a land.

Prairie Stream

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

Quicksand

{T}: Add {C}.
{T}, Sacrifice this land: Target attacking creature without flying gets -1/-2 until end of turn.

Gatta and Luzzu

Flash
When Gatta and Luzzu enters, choose target creature you control. If damage would be dealt to that creature this turn, prevent that damage and put that many +1/+1 counters on it.

Panharmonicon

If an artifact or creature entering causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Aboleth Spawn

Flash
Ward {2}
Probing Telepathy — Whenever a creature entering 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.

Promising Vein

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

Smirking Spelljacker

Flash
Flying
When this creature enters, exile target spell an opponent controls.
Whenever this creature attacks, if a card is exiled with it, you may cast the exiled card without paying its mana cost.

Mystic Gate

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

Faerie Mastermind

Flash
Flying
Whenever an opponent draws their second card each turn, you draw a card.
{3}{U}: Each player draws a card.

Commander Sofia Daguerre

Flash
Crash Landing — When Commander Sofia Daguerre enters, destroy up to one target legendary permanent. That permanent's controller creates a Junk token. (It's an artifact with "{T}, Sacrifice this token: Exile the top card of your library. You may play that card this turn. Activate only as a sorcery.")

Faerie Conclave

This land enters tapped.
{T}: Add {U}.
{1}{U}: This land becomes a 2/1 blue Faerie creature with flying until end of turn. It's still a land.

As Foretold

At the beginning of your upkeep, put a time counter on this enchantment.
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 this enchantment.

Hydroelectric Laboratory

As this land enters, you may pay 3 life. If you don't, it enters tapped.
{T}: Add {U}.

Hydroelectric Specimen

Flash
When this creature enters, you may change the target of target instant or sorcery spell with a single target to this creature.

Hydroelectric Specimen // Hydroelectric Laboratory

Crafty Cutpurse

Flash
When this creature enters, each token that would be created under an opponent's control this turn is created under your control instead.

Stinging Lionfish

Whenever you cast your first spell during each opponent's turn, you may tap or untap target nonland permanent.

Conduit of Ruin

When you cast this spell, you may search your library for a colorless creature card with mana value 7 or greater, reveal it, then shuffle and put that card on top.
The first creature spell you cast each turn costs {2} less to cast.

Seachrome Coast

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

Shire Terrace

Githzerai Monk

Flash
Flying
Psychic Defense — When this creature enters, tap all creatures you don't control.

Sicarian Infiltrator

Flash
Squad {2} (As an additional cost to cast this spell, you may pay {2} any number of times. When this creature enters, create that many tokens that are copies of it.)
Benediction of the Omnissiah — When this creature enters, draw a card.

Malcolm, Alluring Scoundrel

Flash
Flying
Whenever Malcolm deals combat damage to a player, put a chorus counter on it. Draw a card, then discard a card. If there are four or more chorus counters on Malcolm, you may cast the discarded card without paying its mana cost.

Port Town

As this land enters, you may reveal a Plains or Island card from your hand. If you don't, this land enters tapped.
{T}: Add {W} or {U}.

Victory Chimes

Untap this artifact during each other player's untap step.
{T}: A player of your choice adds {C}.

Irrigated Farmland

({T}: Add {W} or {U}.)
This land enters tapped.
Cycling {2} ({2}, Discard this card: Draw a card.)

Hixus, Prison Warden

Flash (You may cast this spell any time you could cast an instant.)
Whenever a creature deals combat damage to you, if Hixus entered this turn, exile that creature until Hixus leaves the battlefield. (That creature returns under its owner's control.)

Fractured Realm

If a triggered ability of a permanent you control triggers, that ability triggers an additional time.
(You may cast either half. That door unlocks on the battlefield. As a sorcery, you may pay the mana cost of a locked door to unlock it.)

Mirror Room

When you unlock this door, create a token that's a copy of target creature you control, except it's a Reflection in addition to its other creature types.
(You may cast either half. That door unlocks on the battlefield. As a sorcery, you may pay the mana cost of a locked door to unlock it.)

Mirror Room // Fractured Realm

Kefnet's Monument

Blue creature spells you cast cost {1} less to cast.
Whenever you cast a creature spell, target creature an opponent controls doesn't untap during its controller's next untap step.

Wavebreak Hippocamp

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

Errant and Giada

Flash
Flying
You may look at the top card of your library any time.
You may cast spells with flash or flying from the top of your library.

Thought Sponge

Flash
This creature enters with a number of +1/+1 counters on it equal to the greatest number of cards an opponent has drawn this turn.
When this creature dies, draw cards equal to its power.

Lavinia, Foil to Conspiracy

Vigilance
Whenever you cast your second spell each turn, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.")
{T}: Add {C}{C}. Activate only during an opponent's turn.

Cactus Preserve

This land enters tapped.
{T}: Add one mana of any type that a land you control could produce.
{3}: Until end of turn, this land becomes an X/X green Plant creature with reach, where X is the greatest mana value among your commanders. It's still a land.

Saiba Cryptomancer

Flash
Backup 1 (When this creature enters, put a +1/+1 counter on target creature. If that's another creature, it gains the following ability until end of turn.)
Hexproof

Ornithopter of Paradise

Skycloud Expanse

Naiad of Hidden Coves

During turns other than yours, spells you cast cost {1} less to cast.

Windshaper Planetar

Flash
Flying
When this creature enters during the declare attackers step, for each attacking creature, you may reselect which player or permanent that creature is attacking. (It can't attack its controller or their permanents.)

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}.

Sunpearl Kirin

Flash
Flying
When this creature enters, return up to one other target nonland permanent you control to its owner's hand. If it was a token, draw a card.

Portal Manipulator

Flash
When this creature enters during the declare attackers step, choose target player and any number of target attacking creatures their opponents control. Those creatures are now attacking that player.

Tishana's Tidebinder

Flash
When this creature enters, counter up to one target activated or triggered ability. If an ability of an artifact, creature, or planeswalker is countered this way, that permanent loses all abilities for as long as this creature remains on the battlefield. (Mana abilities can't be targeted.)

Amphibian Downpour

Flash
Storm (When you cast this spell, copy it for each spell cast before it this turn. You may choose new targets for the copies. Copies become tokens.)
Enchant creature
Enchanted creature loses all abilities and is a blue Frog creature with base power and toughness 1/1.

Deep Gnome Terramancer

Flash
Mold Earth — Whenever one or more lands enter under an opponent's control without being played, you may search your library for a Plains card, put it onto the battlefield tapped, then shuffle. Do this only once each turn.

Gold Myr

Final-Word Phantom

Flash
Flying
During each opponent's end step, you may cast spells as though they had flash.

Stunt Double

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

Ephara, God of the Polis

Indestructible
As long as your devotion to white and blue is less than seven, Ephara isn't a creature.
At the beginning of each upkeep, if you had another creature enter the battlefield under your control last turn, draw a card.

Sigrid, God-Favored

Flash
First strike, protection from God creatures
When Sigrid enters, exile up to one target attacking or blocking creature until Sigrid leaves the battlefield.

Plains

Temple of the False God

{T}: Add {C}{C}. Activate only if you control five or more lands.

Alms Collector

Flash
If an opponent would draw two or more cards, instead you and that player each draw a card.

Selfless Squire

Flash
When this creature enters, prevent all damage that would be dealt to you this turn.
Whenever damage that would be dealt to you is prevented, put that many +1/+1 counters on this creature.

Geyser Drake

Flying
During turns other than yours, spells you cast cost {1} less to cast.

Sakashima's Protege

Flash
Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)
You may have this creature enter as a copy of any permanent that entered this turn.

Glacial Fortress

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

Ioreth of the Healing House

{T}: Untap another target permanent.
{T}: Untap two other target legendary creatures.

Moorland Haunt

{T}: Add {C}.
{W}{U}, {T}, Exile a creature card from your graveyard: Create a 1/1 white Spirit creature token with flying.

Elesh Norn, Mother of Machines

Vigilance
If a permanent entering causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.
Permanents entering don't cause abilities of permanents your opponents control to trigger.

Manakin

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.

Grey Knight Paragon

Flash
Rites of Banishment — When this creature enters, destroy target attacking creature. If that creature is a Demon, exile it instead.

Forbidding Watchtower

This land enters tapped.
{T}: Add {W}.
{1}{W}: This land becomes a 1/5 white Soldier creature until end of turn. It's still a land.

Azorius Keyrune

{T}: Add {W} or {U}.
{W}{U}: This artifact becomes a 2/2 white and blue Bird artifact creature with flying until end of turn.

Pouncing Shoreshark

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.)
Flash
Whenever this creature mutates, you may return target creature an opponent controls to its owner's hand.

Arcane Signet

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

Command Tower

Moderation

You can't cast more than one spell each turn.
Whenever you cast a spell, draw a card.

Restless Anchorage

This land enters tapped.
{T}: Add {W} or {U}.
{1}{W}{U}: Until end of turn, this land becomes a 2/3 white and blue Bird creature with flying. It's still a land.
Whenever this land attacks, create a Map token.

Exotic Orchard

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

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.

Promise of Tomorrow

Whenever a creature you control dies, exile it.
At the beginning of each end step, if you control no creatures, sacrifice this enchantment and return all cards exiled with it to the battlefield under your control.

Kor Haven

{T}: Add {C}.
{1}{W}, {T}: Prevent all combat damage that would be dealt by target attacking creature this turn.

Palladium Myr

Watcher of the Spheres

Flying
Creature spells with flying you cast cost {1} less to cast.
Whenever another creature you control with flying enters, this creature gets +1/+1 until end of turn.

Portal Mage

Flash
When this creature enters 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.)

Oketra's Monument

White creature spells you cast cost {1} less to cast.
Whenever you cast a creature spell, create a 1/1 white Warrior creature token with vigilance.

Silver Myr

Containment Priest

Flash
If a nontoken creature would enter and it wasn't cast, exile it instead.

Cloud Key

As this artifact enters, choose artifact, creature, enchantment, instant, or sorcery.
Spells you cast of the chosen type cost {1} less to cast.

Venser, Shaper Savant

Flash (You may cast this spell any time you could cast an instant.)
When Venser enters, return target spell or permanent to its owner's hand.

Nivix Barrier

Flash (You may cast this spell any time you could cast an instant.)
Defender (This creature can't attack.)
When this creature enters, target attacking creature gets -4/-0 until end of turn.

Werefox Bodyguard

Flash
When this creature enters, exile up to one other target non-Fox creature until this creature leaves the battlefield.
{1}{W}, Sacrifice this creature: You gain 2 life.

Phelia, Exuberant Shepherd

Flash
Whenever Phelia attacks, exile up to one other target nonland permanent. At the beginning of the next end step, return that card to the battlefield under its owner's control. If it entered under your control, put a +1/+1 counter on Phelia.

Inkmoth Nexus

{T}: Add {C}.
{1}: This land becomes a 1/1 Phyrexian Blinkmoth artifact creature with flying and infect until end of turn. It's still a land. (It deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Deserted Beach

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

Blinkmoth Nexus

{T}: Add {C}.
{1}: This land becomes a 1/1 Blinkmoth artifact creature with flying until end of turn. It's still a land.
{1}, {T}: Target Blinkmoth creature gets +1/+1 until end of turn.

Cave of the Frost Dragon

If you control two or more other lands, this land enters tapped.
{T}: Add {W}.
{4}{W}: This land becomes a 3/4 white Dragon creature with flying until end of turn. It's still a land.

Adarkar Wastes

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

Aven Interrupter

Flash
Flying
When this creature enters, exile target spell. It becomes plotted. (Its owner may cast it as a sorcery on a later turn without paying its mana cost.)
Spells your opponents cast from graveyards or from exile cost {2} more to cast.

Heliod, the Warped Eclipse

You may cast spells as though they had flash.
Spells you cast cost {1} less to cast for each card your opponents have drawn this turn.

Heliod, the Radiant Dawn

When Heliod enters, return target enchantment card that isn't a God from your graveyard to your hand.
{3}{U/P}: Transform Heliod. Activate only as a sorcery. ({U/P} can be paid with either {U} or 2 life.)