Morphic Pool

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

Sea-Dasher Octopus

Mutate {1}{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 deals combat damage to a player, draw a card.

Illusory Ambusher

Flash (You may cast this spell any time you could cast an instant.)
Whenever Illusory Ambusher is dealt damage, draw that many cards.

Thought Sponge

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

Lobelia Sackville-Baggins

Flash
Menace
When Lobelia Sackville-Baggins enters the battlefield, exile target creature card from an opponent's graveyard that was put there from the battlefield this turn, then create X Treasure tokens, where X is the exiled card's power.

Ancient Stone Idol

Flash
This spell costs {1} less to cast for each attacking creature.
Trample
When Ancient Stone Idol dies, create a 6/12 colorless Construct artifact creature token with trample.

Growth Spiral

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

Vision Skeins

Zagoth Triome

({T}: Add {B}, {G}, or {U}.)
Zagoth Triome enters the battlefield tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Deep Gnome Terramancer

Flash
Mold Earth — Whenever one or more lands enter the battlefield 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.

Sea of Clouds

Sea of Clouds enters the battlefield tapped unless you have two or more opponents.
{T}: Add {W} or {U}.

Mystic Gate

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

Stunt Double

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

Niambi, Esteemed Speaker

Flash
When Niambi, Esteemed Speaker enters the battlefield, you may return another target creature you control to its owner's hand. If you do, you gain life equal to that creature's mana value.
{1}{W}{U}, {T}, Discard a legendary card: Draw two cards.

Lochmere Serpent

Flash
{U}, Sacrifice an Island: Lochmere Serpent can't be blocked this turn.
{B}, Sacrifice a Swamp: You gain 1 life and draw a card.
{U}{B}: Exile five target cards from an opponent's graveyard. Return Lochmere Serpent from your graveyard to your hand. Activate only as a sorcery.

Command Tower

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

City of Brass

Whenever City of Brass becomes tapped, it deals 1 damage to you.
{T}: Add one mana of any color.

Steam Vents

({T}: Add {U} or {R}.)
As Steam Vents enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

Consider

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

Archivist of Oghma

Flash
Whenever an opponent searches their library, you gain 1 life and draw a card.

Jetmir's Garden

({T}: Add {R}, {G}, or {W}.)
Jetmir's Garden enters the battlefield tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Slitherwisp

Flash
Whenever you cast another spell that has flash, you draw a card and each opponent loses 1 life.

Magma Opus

Magma Opus deals 4 damage divided as you choose among any number of targets. Tap two target permanents. Create a 4/4 blue and red Elemental creature token. Draw two cards.
{U/R}{U/R}, Discard Magma Opus: Create a Treasure token.

Death-Rattle Oni

Flash
This spell costs {2} less to cast for each creature that died this turn.
When Death-Rattle Oni enters the battlefield, destroy all other creatures that were dealt damage this turn.

Flooded Strand

{T}, Pay 1 life, Sacrifice Flooded Strand: Search your library for a Plains or Island card, put it onto the battlefield, then shuffle.

Angel of the Dire Hour

Flash
Flying
When Angel of the Dire Hour enters the battlefield, if you cast it from your hand, exile all attacking creatures.

Liliana's Standard Bearer

Flash
When Liliana's Standard Bearer enters the battlefield, draw X cards, where X is the number of creatures that died under your control this turn.

Aven Interrupter

Flash
Flying
When Aven Interrupter enters the battlefield, 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.

Ashcoat Bear

Flash (You may cast this spell any time you could cast an instant.)

Solitude

Flash
Lifelink
When Solitude enters the battlefield, exile up to one other target creature. That creature's controller gains life equal to its power.
Evoke—Exile a white card from your hand.

Mizzium Meddler

Flash (You may cast this spell any time you could cast an instant.)
When Mizzium Meddler enters the battlefield, you may change a target of target spell or ability to Mizzium Meddler.

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.

Portal Manipulator

Flash
When Portal Manipulator enters the battlefield 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.

Indatha Triome

({T}: Add {W}, {B}, or {G}.)
Indatha Triome enters the battlefield tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Cunning Nightbonder

Flash
Spells with flash you cast cost {1} less to cast and can't be countered.

Construct

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.

Polluted Delta

{T}, Pay 1 life, Sacrifice Polluted Delta: Search your library for an Island or Swamp card, put it onto the battlefield, then shuffle.

The World Tree

The World Tree enters the battlefield tapped.
{T}: Add {G}.
As long as you control six or more lands, lands you control have "{T}: Add one mana of any color."
{W}{W}{U}{U}{B}{B}{R}{R}{G}{G}, {T}, Sacrifice The World Tree: Search your library for any number of God cards, put them onto the battlefield, then shuffle.

Watery Grave

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

Deliberate

Raugrin Triome

({T}: Add {U}, {R}, or {W}.)
Raugrin Triome enters the battlefield tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Raffine's Tower

({T}: Add {W}, {U}, or {B}.)
Raffine's Tower enters the battlefield tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Weeping Angel

Flash
First strike, vigilance
Whenever an opponent casts a creature spell, Weeping Angel isn't a creature until end of turn.
If Weeping Angel would deal combat damage to a creature, prevent that damage and that creature's owner shuffles it into their library.

Ketria Triome

({T}: Add {G}, {U}, or {R}.)
Ketria Triome enters the battlefield tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Phantom Steed

Flash
When Phantom Steed enters the battlefield, exile another target creature you control until Phantom Steed leaves the battlefield.
Whenever Phantom Steed attacks, create a tapped and attacking token that's a copy of the exiled card, except it's an Illusion in addition to its other types. Sacrifice that token at end of combat.

Ferrous Lake

Cathar Commando

Flash
{1}, Sacrifice Cathar Commando: Destroy target artifact or enchantment.

Dualcaster Mage

Flash
When Dualcaster Mage enters the battlefield, copy target instant or sorcery spell. You may choose new targets for the copy.

Glorious Protector

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

Breeding Pool

({T}: Add {G} or {U}.)
As Breeding Pool enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

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.

Words of Wisdom

You draw two cards, then each other player draws a card.

Godless Shrine

({T}: Add {W} or {B}.)
As Godless Shrine enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

Notion Thief

Flash
If an opponent would draw a card except the first one they draw in each of their draw steps, instead that player skips that draw and you draw a card.

Darkwater Catacombs

Phelia, Exuberant Shepherd

Flash
Whenever Phelia, Exuberant Shepherd 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.

Shadow Kin

Flash
At the beginning of your upkeep, each player mills three cards. You may exile a creature card from among the cards milled this way. If you do, Shadow Kin becomes a copy of that card, except it has this ability.

Mysterious Stranger

Flash
When Mysterious Stranger enters the battlefield, for each graveyard with an instant or sorcery card in it, exile target instant or sorcery card from that graveyard. If two or more cards are exiled this way, choose one of them at random and copy it. You may cast the copy without paying its mana cost.

Mocking Doppelganger

Flash
You may have Mocking Doppelganger enter the battlefield as a copy of a creature an opponent controls, except it has "Other creatures with the same name as this creature are goaded." (They attack each combat if able and attack a player other than you if able.)

Sandstalker Moloch

Flash
When Sandstalker Moloch enters the battlefield, if an opponent cast a blue and/or black spell this turn, look at the top four cards of your library. You may reveal a permanent card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.

Savai Triome

({T}: Add {R}, {W}, or {B}.)
Savai Triome enters the battlefield tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Vault of Champions

Vault of Champions enters the battlefield tapped unless you have two or more opponents.
{T}: Add {W} or {B}.

Training Center

Training Center enters the battlefield tapped unless you have two or more opponents.
{T}: Add {U} or {R}.

Green Slime

Flash
When Green Slime enters the battlefield, counter target activated or triggered ability from an artifact or enchantment source. If a permanent's ability is countered this way, destroy that permanent.
Foretell {G} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Tainted Indulgence

Draw two cards. Then discard a card unless there are five or more mana values among cards in your graveyard.

Temple Garden

({T}: Add {G} or {W}.)
As Temple Garden enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

Nymris, Oona's Trickster

Flash
Flying
Whenever you cast your first spell during each opponent's turn, look at the top two cards of your library. Put one of those cards into your hand and the other into your graveyard.

Marsh Flats

{T}, Pay 1 life, Sacrifice Marsh Flats: Search your library for a Plains or Swamp card, put it onto the battlefield, then shuffle.

Werefox Bodyguard

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

Prismari Command

Choose two —
• Prismari Command deals 2 damage to any target.
• Target player draws two cards, then discards two cards.
• Target player creates a Treasure token.
• Destroy target artifact.

Spara's Headquarters

({T}: Add {G}, {W}, or {U}.)
Spara's Headquarters enters the battlefield tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

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.)

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.

Callidus Assassin

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

Deadly Dispute

As an additional cost to cast this spell, sacrifice an artifact or creature.
Draw two cards and create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

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 of your library in a random order.)
You may have Sakashima's Protege enter the battlefield as a copy of any permanent that entered the battlefield this turn.

Exotic Orchard

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

Vizier of Deferment

Flash
When Vizier of Deferment enters the battlefield, you may exile target creature if it attacked or blocked this turn. Return that card to the battlefield under its owner's control at the beginning of the next end step.

Desolate Mire

Spell Queller

Flash
Flying
When Spell Queller enters the battlefield, exile target spell with mana value 4 or less.
When Spell Queller leaves the battlefield, the exiled card's owner may cast that card without paying its mana cost.

Guardian of Faith

Flash
Vigilance
When Guardian of Faith enters the battlefield, any number of other target creatures you control phase out. (Treat them and anything attached to them as though they don't exist until their controller's next turn.)

Kyodai, Soul of Kamigawa

Flash
Flying
When Kyodai, Soul of Kamigawa enters the battlefield, another target permanent gains indestructible for as long as you control Kyodai.
{W}{U}{B}{R}{G}: Kyodai gets +5/+5 until end of turn.

Great Train Heist

Spree (Choose one or more additional costs.)
+ {2}{R} — Untap all creatures you control. If it's your combat phase, there is an additional combat phase after this phase.
+ {2} — Creatures you control get +1/+0 and gain first strike until end of turn.
+ {R} — Choose target opponent. Whenever a creature you control deals combat damage to that player this turn, create a tapped Treasure token.

Radiant Performer

Flash
When Radiant Performer enters the battlefield, if you cast it from your hand, choose target spell or ability that targets only a single permanent or player. Copy that spell or ability for each other permanent or player the spell or ability could target. Each copy targets a different one of those permanents and players.

Windshaper Planetar

Flash
Flying
When Windshaper Planetar enters the battlefield 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.)

Mana Confluence

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

Brainstorm

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

Sigarda's Vanguard

Flash
Flying
Whenever Sigarda's Vanguard enters the battlefield or attacks, choose any number of creatures with different powers. Those creatures gain double strike until end of turn.

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.

Malcolm, Alluring Scoundrel

Flash
Flying
Whenever Malcolm, Alluring Scoundrel 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.

Ertai Resurrected

Flash
When Ertai Resurrected enters the battlefield, 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.

Spectator Seating

Spectator Seating enters the battlefield tapped unless you have two or more opponents.
{T}: Add {R} or {W}.

Faerie Mastermind

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

Activated Sleeper

Flash
You may have Activated Sleeper enter the battlefield as a copy of any creature card in a graveyard that was put there from the battlefield this turn, except it's a Phyrexian in addition to its other types.

Sunscorched Divide

Xander's Lounge

({T}: Add {U}, {B}, or {R}.)
Xander's Lounge enters the battlefield tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Hallowed Fountain

({T}: Add {W} or {U}.)
As Hallowed Fountain enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

Sacred Foundry

({T}: Add {R} or {W}.)
As Sacred Foundry enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

Smirking Spelljacker

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

Crafty Cutpurse

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

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.

Overflowing Basin

Alms Collector

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