Amphin Mutineer

When Amphin Mutineer enters the battlefield, exile up to one target non-Salamander creature. That creature's controller creates a 4/3 blue Salamander Warrior creature token.
Encore {4}{U}{U} ({4}{U}{U}, Exile this card from your graveyard: For each opponent, create a token copy that attacks that opponent this turn if able. They gain haste. Sacrifice them at the beginning of the next end step. Activate only as a sorcery.)

Archaeomancer

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

Aarakocra Sneak

Flying
When Aarakocra Sneak enters the battlefield, you take the initiative.

Yorion, Sky Nomad

Companion — Your starting deck contains at least twenty cards more than the minimum deck size. (If this card is your chosen companion, you may put it into your hand from outside the game for {3} as a sorcery.)
Flying
When Yorion enters the battlefield, exile any number of other nonland permanents you own and control. Return those cards to the battlefield at the beginning of the next end step.

Ajani's Welcome

Whenever a creature enters the battlefield under your control, you gain 1 life.

Agent of Treachery

When Agent of Treachery enters the battlefield, 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.

Arashin Cleric

When Arashin Cleric enters the battlefield, you gain 3 life.

Aethersnipe

When Aethersnipe enters the battlefield, return target nonland permanent to its owner's hand.
Evoke {1}{U}{U} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters the battlefield.)

Archon of Coronation

Flying
When Archon of Coronation enters the battlefield, you become the monarch.
As long as you're the monarch, damage doesn't cause you to lose life. (When a creature deals combat damage to you, its controller still becomes the monarch.)

Angelic Chorus

Whenever a creature enters the battlefield under your control, you gain life equal to its toughness.

Academy Journeymage

This spell costs {1} less to cast if you control a Wizard.
When Academy Journeymage enters the battlefield, return target creature an opponent controls to its owner's hand.

Anointer Priest

Whenever a creature token enters the battlefield under your control, you gain 1 life.
Embalm {3}{W} ({3}{W}, Exile this card from your graveyard: Create a token that's a copy of it, except it's a white Zombie Human Cleric with no mana cost. Embalm only as a sorcery.)

Aether Channeler

When Aether Channeler enters the battlefield, 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.

Aether Adept

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

Angel of Indemnity

Flying, lifelink
When Angel of Indemnity enters the battlefield, return target permanent card with mana value 4 or less from your graveyard to the battlefield.
Encore {6}{W}{W} ({6}{W}{W}, Exile this card from your graveyard: For each opponent, create a token copy that attacks that opponent this turn if able. They gain haste. Sacrifice them at the beginning of the next end step. Activate only as a sorcery.)