Mage's Attendant

When Mage's Attendant enters the battlefield, create a 1/1 blue Wizard creature token with "{1}, Sacrifice this creature: Counter target noncreature spell unless its controller pays {1}."

Ghostly Flicker

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

Aetherstorm Roc

Flying
Whenever Aetherstorm Roc or another creature enters the battlefield under your control, you get {E} (an energy counter).
Whenever Aetherstorm Roc attacks, you may pay {E}{E}. If you do, put a +1/+1 counter on it and tap up to one target creature defending player controls.

Admonition Angel

Flying
Landfall — Whenever a land enters the battlefield under your control, you may exile target nonland permanent other than Admonition Angel.
When Admonition Angel leaves the battlefield, return all cards exiled with it to the battlefield under their owners' control.

Muse Drake

Flying
When Muse Drake enters the battlefield, draw a card.

Plains

Flickerwisp

Flying
When Flickerwisp enters the battlefield, exile another target permanent. Return that card to the battlefield under its owner's control at the beginning of the next end step.

Callous Oppressor

You may choose not to untap Callous Oppressor during your untap step.
As Callous Oppressor enters the battlefield, an opponent chooses a creature type.
{T}: Gain control of target creature that isn't of the chosen type for as long as Callous Oppressor remains tapped.

Banisher Priest

When Banisher Priest enters the battlefield, exile target creature an opponent controls until Banisher Priest leaves the battlefield. (That creature returns under its owner's control.)

Clarion Cathars

When Clarion Cathars enters the battlefield, create a 1/1 white Human creature token.

Spirited Companion

When Spirited Companion enters the battlefield, draw a card.

Cloudblazer

Flying
When Cloudblazer enters the battlefield, you gain 2 life and draw two cards.

Sun Titan

Vigilance
Whenever Sun Titan enters the battlefield or attacks, you may return target permanent card with mana value 3 or less from your graveyard to the battlefield.

Wall of Omens

Defender
When Wall of Omens enters the battlefield, draw a card.

Council of Advisors

When Council of Advisors enters the battlefield, draw a card.

Elite Guardmage

Flying
When Elite Guardmage enters the battlefield, you gain 3 life and draw a card.

Cloudkin Seer

Flying
When Cloudkin Seer enters the battlefield, draw a card.

Felidar Guardian

When Felidar Guardian enters the battlefield, you may exile another target permanent you control, then return that card to the battlefield under its owner's control.

Basalt Monolith

Basalt Monolith doesn't untap during your untap step.
{T}: Add {C}{C}{C}.
{3}: Untap Basalt Monolith.

Palace Jailer

When Palace Jailer enters the battlefield, you become the monarch.
When Palace Jailer enters the battlefield, exile target creature an opponent controls until an opponent becomes the monarch.

Archaeomancer

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

Sol Ring

Swords to Plowshares

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

Aspiring Aeronaut

Flying (This creature can't be blocked except by creatures with flying or reach.)
When Aspiring Aeronaut enters the battlefield, create a 1/1 colorless Thopter artifact creature token with flying.

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.

Counterspell

Eerie Interlude

Exile any number of target creatures you control. Return those cards to the battlefield under their owner's control at the beginning of the next end step.

Peregrine Drake

Flying
When Peregrine Drake enters the battlefield, untap up to five lands.

Brago, King Eternal

Flying
Whenever Brago, King Eternal deals combat damage to a player, exile any number of target nonland permanents you control, then return those cards to the battlefield under their owner's control.

Brinebound Gift

Enchant creature
Whenever Brinebound Gift enters the battlefield or enchanted creature becomes the target of an Aura spell, create a 1/1 white Spirit creature token with flying.
If Brinebound Gift would be put into a graveyard from anywhere, exile it instead.

Brine Comber

Whenever Brine Comber enters the battlefield or becomes the target of an Aura spell, create a 1/1 white Spirit creature token with flying.
Disturb {W}{U} (You may cast this card from your graveyard transformed for its disturb cost.)

Brine Comber // Brinebound Gift

Watcher for Tomorrow

Hideaway 4 (When this creature enters the battlefield, look at the top four cards of your library, exile one face down, then put the rest on the bottom in a random order.)
Watcher for Tomorrow enters the battlefield tapped.
When Watcher for Tomorrow leaves the battlefield, put the exiled card into its owner's hand.

Nimble Innovator

When Nimble Innovator enters the battlefield, draw a card.

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.

Mulldrifter

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

Skyclave Apparition

When Skyclave Apparition enters the battlefield, exile up to one target nonland, nontoken permanent you don't control with mana value 4 or less.
When Skyclave Apparition leaves the battlefield, the exiled card's owner creates an X/X blue Illusion creature token, where X is the mana value of the exiled card.

Teleportation Circle

At the beginning of your end step, exile up to one target artifact or creature you control, then return that card to the battlefield under its owner's control.

Boss's Chauffeur

Boss's Chauffeur enters the battlefield with a number of +1/+1 counters on it equal to one plus the number of other creatures you control.
Alliance — Whenever another creature enters the battlefield under your control, put a +1/+1 counter on Boss's Chauffeur.
When Boss's Chauffeur dies, create a 1/1 green and white Citizen creature token for each +1/+1 counter on it.

Merchant of Secrets

When Merchant of Secrets enters the battlefield, draw a card.

Bazaar Trademage

Flying
When Bazaar Trademage enters the battlefield, draw two cards, then discard three cards.

Arcane Signet

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

Aerial Extortionist

Flying
Whenever Aerial Extortionist enters the battlefield or deals combat damage to a player, exile up to one target nonland permanent. For as long as that card remains exiled, its owner may cast it.
Whenever another player casts a spell from anywhere other than their hand, draw a card.

Aether Adept

When Aether Adept enters the battlefield, return target creature to its owner's hand.

Lena, Selfless Champion

When Lena, Selfless Champion enters the battlefield, create a 1/1 white Soldier creature token for each nontoken creature you control.
Sacrifice Lena: Creatures you control with power less than Lena's power gain indestructible until end of turn.

Fiend Hunter

When Fiend Hunter enters the battlefield, you may exile another target creature.
When Fiend Hunter leaves the battlefield, return the exiled card to the battlefield under its owner's control.

Attended Knight

First strike
When Attended Knight enters the battlefield, create a 1/1 white Soldier creature token.

Riverwise Augur

When Riverwise Augur enters the battlefield, draw three cards, then put two cards from your hand on top of your library in any order.

Soulherder

Whenever a creature is exiled from the battlefield, put a +1/+1 counter on Soulherder.
At the beginning of your end step, you may exile another target creature you control, then return that card to the battlefield under its owner's control.

Cemetery Protector

Flash
When Cemetery Protector enters the battlefield, exile a card from a graveyard.
Whenever you play a land or cast a spell, if it shares a card type with the exiled card, create a 1/1 white Human creature token.

Reflector Mage

When Reflector Mage enters the battlefield, return target creature an opponent controls to its owner's hand. That creature's owner can't cast spells with the same name as that creature until your next turn.