msem-instigator

Tap up to two target creatures.
Flashback {3}{W/U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

When Aethermancer's Companion enters, aetherize up to two other non-Cat permanents you control. (Create tokens that are copies of each of them, then exile them.)
Recite {5}{W}{U} (You may cast this spell from your graveyard for its recite cost. If you do, exile it when it enters or if it would leave the battlefield.)

Flash
When Aethermancer's Familiar enters, at the beginning of the next end step, you may aetherize target creature you control. (To aetherize, create a token that's a copy of it, then exile that token.)

Equipped creature gets +2/+1.
Equip multicolored creature {1}
Equip {2}

Return target spell or creature to its owner's hand.
Quickdraw {U} (When a creature you control blocks or becomes blocked, you may cast this spell for {U}.)

Target creature you control fights target creature you don't control. You may discard a card. If you do, draw a card.

At the beginning of your end step, you lose 3 life unless you sacrifice a creature.

When Affluent Knight enters, recruit, then recruit again. (To recruit, create a 0/0 white Soldier Army creature token, then put a +1/+1 counter on each Army you control.)

When Aftermath of the Surge enters, create two Treasure tokens.
{1}{U}, Sacrifice two artifacts: Draw two cards.
{3}{U}, Sacrifice four artifacts: Create an 8/8 blue Kraken creature token. It can't block this turn.

Creatures you control get +1/+1 until end of turn.
Lifecycle {3} ({3}, Discard this card: Create two tapped 1/1 colorless Elemental creature tokens.)

Target player mills X cards, where X is the number of cards named Against the Waves in your graveyard. Draw a card, then conjure three cards named Against the Waves and shuffle them into your main library.

When Ageless Ascetic enters, return up to one target instant or sorcery card from your graveyard to your hand.

Flying
When Ageless Lorekeeper enters, you may discard your hand. When you do, draw three cards.

Whenever a land you control enters, untap Ageless Wanderer.
{1}, {T}: Add one mana of any color.

Whenever a creature you control dies, put a +1/+1 counter on Agent of Andazir.

Flash
When Agent of Deception enters, counter target creature or planeswalker spell unless its controller pays {X}, where X is your devotion to blue. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.)

Flash
When Agent of Equilibrium enters, destroy target creature or planeswalker an opponent controls that was dealt damage this turn.

Whenever Agent of Vitu-Ghazi deals combat damage to a player, investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

Target creature you control deals damage equal to its power to target creature you don't control.

Poisonous 1 (Whenever this creature deals combat damage to a player, that player gets a poison counter.)
At the beginning of your upkeep, destroy target artifact or enchantment if its controller is poisoned.

Agonizing Syphon deals 3 damage to any target and you gain 3 life.

I, II — Search your library for a basic land card, reveal it, put it into your hand, then shuffle.
Discovery — {4}: You gain 2 life.

Enchant land
When Aid from Martoob enters, recruit. (Create a 0/0 white Soldier Army creature token, then put a +1/+1 counter on each Army you control.)
When enchanted land is tapped for mana, add one mana of any color.

Move up to one +1/+1 counter from a creature you control to target creature you control. Then that creature fights target creature you don't control.

Ainok Alpha can't be blocked by more than one creature.
Other Hounds you control get +1/+1 and can't be blocked by more than one creature.