msem-instigator

Choose two —
• Counter target spell unless its controller pays {6}.
• Target player draws two cards, then discards a card.
• Creatures target player doesn't control get -3/-0 until end of turn.
• Exile up to two target creatures, then return those cards to the battlefield under their owners' control.

Draw three cards.
Reprise {5}{U}{U} (As you cast an instant or sorcery spell, you may exile one card with reprise from your graveyard and pay its reprise cost. If you do, add its effects to that spell.)

Counter target spell unless its controller pays {2} for each Wizard on the battlefield.

Return target nonland permanent to its owner's hand.
Reprise {2}{U} (As you cast an instant or sorcery spell, you may exile one card with reprise from your graveyard and pay its reprise cost. If you do, add its effects to that spell.)

Counter target spell unless its controller pays {2}. If that spell targets you or a permanent you control, counter that spell instead.

Flying
When Messenger of the Heavens enters, surveil 1.
Whenever Messenger of the Heavens deals combat damage to a player, exile any number of target creatures in its pack, then return them to the battlefield under your control. (Two or more creatures you control with equal power are in a pack.)

Enchant creature or artifact
When Meticulous Process enters, create a Vial token. (It's an artifact with “{1}, Sacrifice this and another permanent: Draw a card. Activate only during your turn.”)
Enchanted permanent doesn't untap during its controller's untap step.

Create a 2/2 blue Jellyfish enchantment creature token with flying.
Flashback {4}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Whenever you discard a card, choose up to one that hasn't been chosen this turn —
• Draw a card.
• Tap target creature. Put a stun counter on it.
• Create a 2/2 blue Jellyfish enchantment creature token with flying.

Flying
When Midnight Visitor enters, you may return target creature to its owner's hand.

Flash
You may cast the first spell that's an enchantment, instant, or sorcery with mana value 1 you cast each turn without paying its mana cost.

Whenever you cast an instant or sorcery spell, target player mills a card.

When Mindbreak Artisan enters, you may search your library for an artifact card, reveal it, shuffle, then put that card on top.
Other artifacts you control have “You may choose not to untap this artifact during your untap step” and “{3}{U}{U}, {T}: Gain control of target creature for as long as you control this artifact and it remains tapped.”

Flying
If Mindbreaker Sphinx would deal combat damage to a player, you may prevent it. If you do, that player mills X cards, where X is Mindbreaker Sphinx's power. If two cards that share a card type were milled this way, put a +1/+1 counter on Mindbreaker Sphinx.

Exile target spell. Then that card's owner may return it to their hand. If they do, draw a card.

Flying (This creature can't be blocked except by creatures with flying or reach.)
Whenever Mindscreech Drake deals combat damage to a player, that player mills three cards.

When Mineral Expert enters, surveil 1. When you do, you may return target instant or sorcery card from your graveyard to your hand. (Look at the top card of your library. You may put that card into your graveyard.)

When Minister of Madness enters, create a 0/1 blue Weird creature token with flying.
{2}{U}, Sacrifice a creature: Search your library for an instant or sorcery card with mana value equal to 1 plus the sacrificed creature's mana value, exile that card, then shuffle. Then you may cast that card without paying its mana cost. Activate only as a sorcery.

{2}{U}, Remove a counter from a permanent you control: If it was a +1/+1 counter, draw a card. If it was a lore counter, put a +1/+1 counter on Minnow's Accomplice. Activate only as a sorcery.

Prowess

Reverberate {3}{U} (When you cast this spell, copy it if you paid its reverberate cost. You may choose new targets for the copy.)
Create a token that's a copy of target creature you control.

The next time you cast an instant or sorcery spell this turn, copy that spell. You may choose new targets for the copy.
Acquiesce (If you cast this spell from your hand, exile it as it resolves. When one or more creatures you control deal combat damage to an opponent, you may cast this card from exile without paying its mana cost.)

Prowess
Whenever you cast your first noncreature spell during each of your turns, create a 1/1 blue Reflection Wizard creature token with prowess.

Target creature gets +1/+1 and gains distorted until end of turn. (It can be blocked by tapped creatures but not untapped creatures.)
Put the bottom card of your library into your hand.

Flying, ward {2}
At the beginning of your upkeep, if Mirrorwing Commander is embattled, create a token that's a copy of it. (A creature is embattled if it has a counter on it or a permanent you control attached to it.)