msem-instigator

Play with the top card of your library revealed.
You may cast creature spells from the top of your library.
You may pay {W}{U}{B}{R}{G} rather than pay the mana cost for creature spells you cast.

Flying
Whenever AOSE Skydrone deals combat damage to a player, draw a card.

Slipstream (This creature can't be blocked as long as only creatures with slipstream are attacking.)
{4}{B}{B}, {T}, Sacrifice Abalone Abomination: Create an X/X black Horror creature token, where X is the number of cards in your graveyard.

Counter target spell. If that spell is countered this way, put it on the bottom of its owner's library instead of putting it into its owner's graveyard. You may put up to three target cards from your graveyard on the bottom of your library in any order.

All creatures get -4/-4 until end of turn. If a creature would die this turn, exile it instead.

Put a +1/+1 counter on target creature. Prevent all combat damage other creatures would deal this turn.

Haste
Whenever Abominable Auteur attacks, you may return target creature card with mana value 3 or less from your graveyard to the battlefield. If that card's mana value was 1 or less, it enters tapped and attacking.

Menace
Whenever Abomination Blackguard deals combat damage to an opponent, you may draw a card. If you do, you lose 1 life.

When Abyssal Pact enters, you draw two cards and each player loses 2 life.
Players can't gain life.
Damage can't be prevented.

Target player mills X cards, where X is the number of cards in your graveyard.
Flashback {3}{U/B}{U/B} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

This spell costs {2} less to cast if you've cast both an instant spell and a sorcery spell this turn.
Haste

Flash
Flying, first strike, lifelink

Creatures your opponents control get -1/-0.

Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.
Draw a card.

Exile a nonland card from target opponent's graveyard. Copy it. You may cast the copy without paying its mana cost. (Copies of permanents enter as tokens.)

Gain control of target creature until end of turn. Untap that creature. It gains haste until end of turn.
Agonize (You may cast this card from your graveyard by putting a -1/-1 counter on a creature you control in addition to paying its other costs. Then exile this card.)

Whenever a -1/-1 counter is put on a creature, you may create a 1/1 green Elf Druid creature token.

Search your library for a creature card with mana value 3 or less, put it onto the battlefield, then shuffle. It gains haste until end of turn. Return it to your hand at the beginning of the end step.

Flying
Whenever another creature you control enters, Adavene, Dean of the Arts deals 1 damage to each opponent.
Whenever a creature you control deals combat damage to a player, you may exile it, then return it to the battlefield.

When Adept Electromancer enters, scry 2, then reveal the top card of your library. If it's an instant or sorcery card, put it into your hand.

Prowess
When Adept of Signals enters, create a Vial token. (It's an artifact with “{1}, Sacrifice this and another permanent: Draw a card. Activate only during your turn.”)
Tokens you control have “{2}, {T}: Sacrifice this token: Draw a card.”

Flash
When Adiran Distractor enters, return up to one target creature you control and up to one target creature you don't control to their owners' hands.

Converge — Admin of Asthenia enters with a +1/+1 counter on it for each color of mana spent to cast it.
Admin of Asthenia can't attack unless its power is 4 or greater.

Whenever you cast a Pirate spell, create a 1/1 blue and red Pirate creature token with haste.

Flying
As long as there are five or more different creature types among creatures you control, Adventuring Guildmage gets +1/+0 and has hexproof.