msem-instigator

Flying, lifelink
Whenever you gain life, each opponent loses 1 life.
{4}{B}{B}: Create a 1/1 black Vampire creature token with lifelink for each nontoken creature that died this turn.

Enchant creature you control
When Thassa's Benefaction enters, scry 2.
Enchanted creature gets +1/+0 and has flying.

As this permanent transforms into The All-Consuming Swarm, counters on her become loyalty counters instead.
[+2]: Create three 1/1 black and green Insect creature tokens with flying.
[–3]: For each permanent type, each opponent sacrifices a permanent of that type.

At the beginning of the next end step, create X 1/1 white Spirit creature tokens with flying, where X is the number of creatures that died this turn.
Reconstruct {2}{W}{B} (You may cast this from your graveyard for its reconstruct cost reduced by the mana value of a permanent you sacrifice as you cast it this way. Then exile this.)

Flying, haste
Whenever The Branded Usurper attacks, it deals 2 damage to any target.
If you would lose the game, instead exile The Branded Usurper. Your life total becomes 0. Until an opponent's next turn, you can't lose the game and you can't gain life. Take an extra turn after this one.

Flying
Whenever a creature attacks you or a planeswalker you control, put a -1/-1 counter on that creature.

Flying, menace
Whenever another creature you control deals combat damage to a player, sacrifice it.
If you would draw a card, you may instead return a creature card from your graveyard to your hand.

Flying
Creatures you control have “{T}: Add {C} or one mana of any color.”
{X}: The Finest Specimen gets +X/+X until end of turn.

[+1]: Return target nonland permanent to its owner's hand. That player loses 2 life.
[0]: Create a 1/1 blue Bird creature token with flying for each loyalty counter on The Flock.
[–6]: You get an emblem with “If a permanent you don't control would leave the battlefield, you may instead exile it, then return that card to the battlefield under your control. It's a 1/1 blue Bird creature with flying.”

Flying
When you cast The Grand Simurgh, search your graveyard and the top five cards of your library for any number of nonlegendary creature cards with total mana value 5 or less and put those cards onto the battlefield, then shuffle.

Flying
You pay {0} to cast your first spell each turn rather than its mana cost. If you cast a spell with {X} in its mana cost this way, X is 8.

[+1]: Add {W}{U}{B}{R}{G}.
[–1]: Exile the top three cards of your library. Until end of turn, you may play cards exiled with this permanent.
[–3]: Create a 5/5 Archon creature token that's all colors and has flying and “When this creature enters, it deals 5 damage to any target.”

Flying
Whenever one or more other creatures die for the first time each turn, journey. (To journey, exile the top card of your library face up. Whenever a creature you control deals combat damage to an opponent, put a journeyed card you own into your hand.)

(Transform this if it's not attached to a creature.)
Enchant creature you control
The Scourgebone Pact's rider gets +2/+1, has flying, lifelink and deathtouch, and can't dismount. (This still transforms into a creature if its rider leaves the battlefield.)

Flying
Spirited (When this creature enters, you may activate one of its activated abilities without paying its costs.)
Harmony — Draw three cards.
{2}{G}{G}: Harmonize. (Trigger up to one harmony of a permanent you control.)

Create a 1/1 white Spirit creature token with flying. (Then exile this card. You may cast the artifact later from exile.)

Whenever The Wicker Lord or another Scarecrow you control enters, create a 1/1 black Bird creature token with flying for each Scarecrow you control.
{4}, Sacrifice a Scarecrow: Return target artifact card from your graveyard to the battlefield.

Flying, menace, trample
When The Wickerscreech of Gatstaf dies, destroy target nonland permanent an opponent controls.
Foreshadow {13}. This costs {1} less for each nonland card in your graveyard. (You may cast this spell for its foreshadow cost. If you do, also trigger its “dies” abilities when it enters.)

Whenever The Winged Steed attacks, create a 4/4 red Dragon creature token with flying that's tapped and attacking. Exile that token at end of combat.
Crew 2 (Tap any number of creatures you control with total power 2 or greater: This Vehicle becomes an artifact creature until end of turn.)

Flying, haste
Thermal Surger can't block.
When Thermal Surger enters, you may sacrifice a land or exile a land card from your graveyard. If you do, put a +1/+1 counter on Thermal Surger.

Flying
Whenever Theurgic Flock deals combat damage to a player, if it doesn't have a +1/+1 counter on it, put a +1/+1 counter on it.

Flying
When Thief of Mortals deals combat damage to a player, as long as you control Thief of Mortals, gain control of target nonland permanent that player controls, and that permanent doesn't untap during its controller's untap step. Tap it.
At the beginning of each end step, if you control five or more permanents you don't own, you win the game.

Flying
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)

Flying
When Thunder Shrike enters, choose up to two target permanents. For each of those permanents, you may tap or untap it.

Target creature gets +1/+1 for each creature you control and gains flying and vigilance until end of turn.