Fetid Pools

({T}: Add {U} or {B}.)
Fetid Pools enters tapped.
Cycling {2} ({2}, Discard this card: Draw a card.)

Ravenous Chupacabra

When Ravenous Chupacabra enters, destroy target creature an opponent controls.

Morphic Pool

Morphic Pool enters tapped unless you have two or more opponents.
{T}: Add {U} or {B}.

Noxious Gearhulk

Menace
When Noxious Gearhulk enters, you may destroy another target creature. If a creature is destroyed this way, you gain life equal to its toughness.

Mulldrifter

Flying
When Mulldrifter enters, draw two cards.
Evoke {2}{U} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)

Evacuation

Return all creatures to their owners' hands.

Agent of Treachery

When Agent of Treachery enters, gain control of target permanent.
At the beginning of your end step, if you control three or more permanents you don't own, draw three cards.

Atris, Oracle of Half-Truths

Menace
When Atris, Oracle of Half-Truths enters, target opponent looks at the top three cards of your library and separates them into a face-down pile and a face-up pile. Put one pile into your hand and the other into your graveyard.

Deadeye Navigator

Soulbond (You may pair this creature with another unpaired creature when either enters. They remain paired for as long as you control both of them.)
As long as Deadeye Navigator is paired with another creature, each of those creatures has "{1}{U}: Exile this creature, then return it to the battlefield under your control."

Curfew

Each player returns a creature they control to its owner's hand.

Diabolic Tutor

Search your library for a card, put that card into your hand, then shuffle.

Ghostly Flicker

Exile two target artifacts, creatures, and/or lands you control, then return those cards to the battlefield under your control.

Talisman of Dominance

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

Sunken Hollow

({T}: Add {U} or {B}.)
Sunken Hollow enters tapped unless you control two or more basic lands.

Evil Twin

You may have Evil Twin enter as a copy of any creature on the battlefield, except it has "{U}{B}, {T}: Destroy target creature with the same name as this creature."

Baleful Strix

Flying, deathtouch
When Baleful Strix enters, draw a card.

Consuming Tide

Each player chooses a nonland permanent they control. Return all nonland permanents not chosen this way to their owners' hands. Then you draw a card for each opponent who has more cards in their hand than you.

Night's Whisper

Solemn Simulacrum

When Solemn Simulacrum enters, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
When Solemn Simulacrum dies, you may draw a card.

Choked Estuary

As Choked Estuary enters, you may reveal an Island or Swamp card from your hand. If you don't, Choked Estuary enters tapped.
{T}: Add {U} or {B}.

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice Mind Stone: Draw a card.

Circuit Mender

When Circuit Mender enters, you gain 2 life.
When Circuit Mender leaves the battlefield, draw a card.

Sky Diamond

Demonic Tutor

Run Away Together

Choose two target creatures controlled by different players. Return those creatures to their owners' hands.

Flood of Tears

Return all nonland permanents to their owners' hands. If you return four or more nontoken permanents you control this way, you may put a permanent card from your hand onto the battlefield.

Swamp

Geistwave

Return target nonland permanent to its owner's hand. If you controlled that permanent, draw a card.

Quickling

Flash (You may cast this spell any time you could cast an instant.)
Flying
When Quickling enters, sacrifice it unless you return another creature you control to its owner's hand.

Chain of Vapor

Return target nonland permanent to its owner's hand. Then that permanent's controller may sacrifice a land of their choice. If the player does, they may copy this spell and may choose a new target for that copy.

Venser, Shaper Savant

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

Negate

Waterfront District

Waterfront District enters tapped.
{T}: Add {U} or {B}.
{2}{U}{B}, {T}, Sacrifice Waterfront District: Draw a card.

Toxic Deluge

As an additional cost to cast this spell, pay X life.
All creatures get -X/-X until end of turn.

Ray of Command

Untap target creature an opponent controls and gain control of it until end of turn. That creature gains haste until end of turn. When you lose control of the creature, tap it.

Sol Ring

Witch's Cottage

({T}: Add {B}.)
Witch's Cottage enters tapped unless you control three or more other Swamps.
When Witch's Cottage enters untapped, you may put target creature card from your graveyard on top of your library.

Hostage Taker

When Hostage Taker enters, exile another target creature or artifact until Hostage Taker leaves the battlefield. You may cast that card for as long as it remains exiled, and mana of any type can be spent to cast that spell.

Creeping Tar Pit

Creeping Tar Pit enters tapped.
{T}: Add {U} or {B}.
{1}{U}{B}: Creeping Tar Pit becomes a 3/2 blue and black Elemental creature until end of turn and can't be blocked this turn. It's still a land.

Charcoal Diamond

Charcoal Diamond enters tapped.
{T}: Add {B}.

Contaminated Aquifer

({T}: Add {U} or {B}.)
Contaminated Aquifer enters tapped.

Mind Flayer

Dominate Monster — When Mind Flayer enters, gain control of target creature for as long as you control Mind Flayer.

Candlekeep Sage

Commander creatures you own have "When this creature enters or leaves the battlefield, draw a card."

Cavern Harpy

Flying
When Cavern Harpy enters, return a blue or black creature you control to its owner's hand.
Pay 1 life: Return Cavern Harpy to its owner's hand.

Snap

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

Shipwreck Marsh

Shipwreck Marsh enters tapped unless you control two or more other lands.
{T}: Add {U} or {B}.

An Offer You Can't Refuse

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

Trenzalore Clocktower

{T}: Add {U}. Put a time counter on Trenzalore Clocktower.
{1}{U}, {T}, Remove twelve time counters from Trenzalore Clocktower and exile it: Shuffle your graveyard and hand into your library, then draw seven cards. Activate only if you control a Time Lord.

Urborg, Tomb of Yawgmoth

Each land is a Swamp in addition to its other land types.

Underground River

{T}: Add {C}.
{T}: Add {U} or {B}. Underground River deals 1 damage to you.

Otawara, Soaring City

{T}: Add {U}.
Channel — {3}{U}, Discard Otawara, Soaring City: Return target artifact, creature, enchantment, or planeswalker to its owner's hand. This ability costs {1} less to activate for each legendary creature you control.

Thought Vessel

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

Massacre Wurm

When Massacre Wurm enters, creatures your opponents control get -2/-2 until end of turn.
Whenever a creature an opponent controls dies, that player loses 2 life.

Ertai Resurrected

Flash
When Ertai Resurrected enters, choose up to one —
• Counter target spell, activated ability, or triggered ability. Its controller draws a card.
• Destroy another target creature or planeswalker. Its controller draws a card.

Archaeomancer

When Archaeomancer enters, return target instant or sorcery card from your graveyard to your hand.

Unsummon

Return target creature to its owner's hand.

War Room

{T}: Add {C}.
{3}, {T}, Pay life equal to the number of colors in your commanders' color identity: Draw a card.

Arcane Signet

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

Thassa, Deep-Dwelling

Indestructible
As long as your devotion to blue is less than five, Thassa isn't a creature.
At the beginning of your end step, exile up to one other target creature you control, then return that card to the battlefield under your control.
{3}{U}: Tap another target creature.

Erratic Portal

{1}, {T}: Return target creature to its owner's hand unless its controller pays {1}.

Command Tower

Watery Grave

({T}: Add {U} or {B}.)
As Watery Grave enters, you may pay 2 life. If you don't, it enters tapped.

Drowned Catacomb

Drowned Catacomb enters tapped unless you control an Island or a Swamp.
{T}: Add {U} or {B}.

Cabal Coffers

{2}, {T}: Add {B} for each Swamp you control.

Auton Soldier

You may have Auton Soldier enter as a copy of any creature on the battlefield, except it isn't legendary, is an artifact in addition to its other types, and has myriad. (Whenever it attacks, for each opponent other than defending player, you may create a token copy that's tapped and attacking that player or a planeswalker they control. Exile the tokens at end of combat.)

Reanimate

Put target creature card from a graveyard onto the battlefield under your control. You lose life equal to its mana value.

Vedalken Orrery

You may cast spells as though they had flash.

Arcane Denial

Counter target spell. Its controller may draw up to two cards at the beginning of the next turn's upkeep.
You draw a card at the beginning of the next turn's upkeep.

Sanctum of Eternity

{T}: Add {C}.
{2}, {T}: Return target commander you own from the battlefield to your hand. Activate only during your turn.

Sakashima the Impostor

You may have Sakashima the Impostor enter as a copy of any creature on the battlefield, except its name is Sakashima the Impostor, it's legendary in addition to its other types, and it has "{2}{U}{U}: Return this creature to its owner's hand at the beginning of the next end step."

Crystal Shard

{3}, {T} or {U}, {T}: Return target creature to its owner's hand unless its controller pays {1}.

The Master, Formed Anew

Body Thief — When you cast this spell, you may exile a creature you control and put a takeover counter on it.
You may have The Master, Formed Anew enter as a copy of a creature card in exile with a takeover counter on it.

Undercity Sewers

({T}: Add {U} or {B}.)
Undercity Sewers enters tapped.
When Undercity Sewers enters, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Counterspell

Callidus Assassin

Flash
Polymorphine — You may have Callidus Assassin enter tapped as a copy of any creature on the battlefield, except it has "When this creature enters, destroy up to one other target creature with the same name as this creature."

Gonti, Lord of Luxury

Deathtouch
When Gonti, Lord of Luxury enters, look at the top four cards of target opponent's library, exile one of them face down, then put the rest on the bottom of that library in a random order. You may cast that card for as long as it remains exiled, and mana of any type can be spent to cast that spell.

Clever Impersonator

You may have Clever Impersonator enter as a copy of any nonland permanent on the battlefield.

Ice Tunnel

({T}: Add {U} or {B}.)
Ice Tunnel enters tapped.

Essence Flux

Exile target creature you control, then return that card to the battlefield under its owner's control. If it's a Spirit, put a +1/+1 counter on it.

Sower of Temptation

Flying
When Sower of Temptation enters, gain control of target creature for as long as Sower of Temptation remains on the battlefield.

Alchemist's Retrieval

Cleave {1}{U} (You may cast this spell for its cleave cost. If you do, remove the words in square brackets.)
Return target nonland permanent [you control] to its owner's hand.

Island

Dimir Signet

Aether Channeler

When Aether Channeler enters, choose one —
• Create a 1/1 white Bird creature token with flying.
• Return another target nonland permanent to its owner's hand.
• Draw a card.

Phyrexian Metamorph

({U/P} can be paid with either {U} or 2 life.)
You may have Phyrexian Metamorph enter as a copy of any artifact or creature on the battlefield, except it's an artifact in addition to its other types.

Equilibrium

Whenever you cast a creature spell, you may pay {1}. If you do, return target creature to its owner's hand.

Disallow

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

Temple of Deceit

Temple of Deceit enters tapped.
When Temple of Deceit enters, scry 1.
{T}: Add {U} or {B}.

Familiar's Ruse

As an additional cost to cast this spell, return a creature you control to its owner's hand.
Counter target spell.