Abjure

As an additional cost to cast this spell, sacrifice a blue permanent.
Counter target spell.

Agoraphobia

Enchant creature
Enchanted creature gets -5/-0.
{2}{U}: Return Agoraphobia to its owner's hand.

Aquus Steed

{2}{U}, {T}: Target creature gets -2/-0 until end of turn.

Archaeomancer

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

Aboshan's Desire

Enchant creature
Enchanted creature has flying.
Threshold — Enchanted creature has shroud as long as seven or more cards are in your graveyard. (It can't be the target of spells or abilities.)

Avizoa

Flying
{0}: Avizoa gets +2/+2 until end of turn. You skip your next untap step. Activate only once each turn.

Artificer's Epiphany

Draw two cards. If you control no artifacts, discard a card.

Azimaet Drake

Flying
{U}: Azimaet Drake gets +1/+0 until end of turn. Activate only once each turn.

Anchor to the Aether

Put target creature on top of its owner's library. Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Aminatou's Augury

Exile the top eight cards of your library. You may put a land card from among them onto the battlefield. Until end of turn, for each nonland card type, you may cast a spell of that type from among the exiled cards without paying its mana cost.

Aboshan, Cephalid Emperor

Tap an untapped Octopus you control: Tap target permanent.
{U}{U}{U}: Tap all creatures without flying.

Amoeboid Changeling

Changeling (This card is every creature type.)
{T}: Target creature gains all creature types until end of turn.
{T}: Target creature loses all creature types until end of turn.

Aquamoeba

Discard a card: Switch Aquamoeba's power and toughness until end of turn.

Aeon Chronicler

Aeon Chronicler's power and toughness are each equal to the number of cards in your hand.
Suspend X—{X}{3}{U}. X can't be 0.
Whenever a time counter is removed from Aeon Chronicler while it's exiled, draw a card.

Amphin Cutthroat

The Unspeakable

Flying, trample
Whenever The Unspeakable deals combat damage to a player, you may return target Arcane card from your graveyard to your hand.

Anthroplasm

Anthroplasm enters with two +1/+1 counters on it.
{X}, {T}: Remove all +1/+1 counters from Anthroplasm and put X +1/+1 counters on it.