msem-instigator

Skip your draw step.
At the beginning of your end step, discard a card. If you do, create a 4/4 white Angel creature token with flying. If you can't, sacrifice Mark of Hubris.

Whenever one or more cards are put into exile from anywhere, target opponent loses 1 life.
Whenever one or more creatures you control deal combat damage to a player, you may pay 2 life. If you do, purge. (Exile two cards that share a type from graveyards. If you do, draw a card.)

Flying, deathtouch
Whenever an opponent loses life for the first time each turn, that player loses 1 life and you gain 1 life.

Flying, haste
You may reveal each card you draw as you draw it. Whenever you reveal a creature card with mana value 1 or less this way, create a token that's a copy of it. That copy gains haste until end of turn.

[+1]: You may play an additional land this turn.
[–1]: Discard a card. If you do, return target creature, land or sorcery card from your graveyard to your hand.
[–5]: Create Thrice-Folded Lotus, a colorless Masterpiece artifact token with “{T}: Add three mana of any one color.” and “{3}, {T}: This artifact deals 3 damage to any target.”

When Phantom Threader enters the battlefield, create a white Aura enchantment token named Spectral Whispers attached to target creature. The token has enchant creature and “Enchanted creature has double strike as long as you control it. Otherwise, it can't attack or block.”

Flying
Morph {5}{W}{W} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)
When you turn Pinnacle Seraph face up, destroy all other creatures.

{T}: Add {C}. You gain 1 life.
Pristine Frame gets +2/+2 and has flying as long as you have 25 or more life.

Extort (Whenever you cast a spell, you may pay {W/B}. If you do, each opponent loses 1 life and you gain that much life.)
Whenever Protective Patron extorts a creature spell, that creature gains indestructible until your next turn.

Trample, haste
Erratic (When this creature dies, reveal the top four cards of your library. Put a creature card that costs less than this revealed this way onto the battlefield and the rest on the bottom of your library in any order.)
At the beginning of the end step, sacrifice Purgator of Storms.

Destroy target tapped creature, then untap all creatures you control.

When Queue Bouncer enters the battlefield, return target creature to its owner's hand. If you control another Actor, instead put that creature on top of its owner's library.

Razing Throng's power and toughness are each equal to the number of creatures you control.
Whenever one or more cards are put into exile from anywhere, create a 1/1 white Cleric creature token.
{2}{W}{W}: Exile a nonland card from a graveyard. You gain 3 life.

Whenever a creature dealt damage by Rei's Betrayer this turn dies, you gain life equal to that creature's toughness.

Exile the top two cards of your library. Until end of turn, you may play those cards. Add {R} for each creature card exiled this way.

Trial 4 (As you cast this spell, an opponent of your choice may pay 4 life. If they don't, they fail the trial.)
Put target creature card from a graveyard onto the battlefield under your control. That creature gains haste. Sacrifice it at the beginning of the next end step unless the trial was failed.

Enchant creature
Enchanted creature can't be blocked.
Whenever enchanted creature deals combat damage to a player, you may aetherize it. (To aetherize, create a token that's a copy of it, then exile that token.)

Trample
Whenever Saghira, Divinity's Usurper attacks, you may pay {1}{G}. If you do, destroy target artifact, enchantment, or creature with flying.

{U}, Sacrifice Seal of Insights: Look at the top four cards of your library. Put one into your hand and the rest on the bottom of your library in any order.

You may have Shaper of the Formless enter the battlefield as a copy of any creature on the battlefield, except it has “{2}{U}: Target face-down creature becomes a copy of this creature until end of turn. Turn that creature face up. At the beginning of the next cleanup step, turn it face down.”

When Shifty Squirrel enters the battlefield, you gain 3 life.
Sacrifice a creature: Transform Shifty Squirrel.

Mark (Whenever this creature attacks, mark target creature until end of turn.)
Marked creatures your opponents control lose all abilities.

This spell costs {2} less to cast for each face-down creature you control.
Flying

Counter target spell unless its controller pays {1} and 3 life.

Skylight Fortress enters the battlefield tapped.
When Skylight Fortress enters the battlefield, you may search your library for a card named Skylight Fortress, reveal it, put it into your hand, then shuffle.
{T}: Add {C}.