msem-instigator

Until end of turn, target creature loses all abilities and becomes a colorless Human with base power and toughness 1/1 and no name.

Flash
When Aokara Redeemer enters, exile another target permanent you control. Return that card to the battlefield under your control at the beginning of the next end step.

Flash
Enchant creature
When Arcane Anesthesia enters, tap enchanted creature.
Enchanted creature doesn't untap during its controller's untap step.

When Artisan's Genius enters, you may tap three untapped artifacts or other enchantments you control. If you do, draw three cards.
{5}{W}{U}, Exile Artisan's Genius: Return any number of artifact or enchantment cards with different names from your graveyard to your hand.

Whenever a nonbasic land becomes tapped or enters tapped, it doesn't untap during its controller's untap steps for as long as Ataraxia remains on the battlefield.

{2}: Atieh's Acolyte gains your choice of flying, vigilance, or lifelink until end of turn.
Whenever another Angel or Nephilim you control enters, put a +1/+1 counter on Atieh's Acolyte.
Surpass {4}{W}{U} ({4}{W}{U}: Transform this creature. This costs {1} less to activate for each counter on it. Activate only as a sorcery.)

Whenever Atieh's Destiny or another creature you control enters, you gain 1 life and scry 1.

Flying
Whenever Atieh's Disciple attacks, scry 1.

Flying, vigilance, lifelink
Whenever Atieh's Favored attacks, put a +1/+1 counter on each other Angel and/or Nephilim creature you control.

Flying, hexproof
At the beginning of your end step, put an exiled card with an ancestry counter on it on the bottom of its owner's library, then scry 2. If there is exactly one card exiled with an ancestry counter on it, transform Atieh.

Transcend (Activate as a sorcery to gain the next type and a +1/+1 counter.)
Flash
When Atieh enters, return target noncreature spell to its owner's hand.
{W}{U}: Angel — You gain 2 life and draw a card.
{2}{W}{U}: Elder — Atieh gains “Each opponent can't cast more than one spell each turn.”

(Add a quest counter as this enters. Sacrifice after 3.)
1, 2 — At the beginning of your end step, if you cast no spells this turn, add a quest counter.
3 — Untap each creature you control. Until your next turn, they gain “{T}: Scry 1.”
Scry 2, then draw two cards. You gain 2 life.

Flying, vigilance
When Augur of Pathways enters, surveil 1.

{T}, Tap an untapped creature you control: You draw a card and you gain 1 life.

Flying
When Aven Strategist enters, return up to one target creature to its owner's hand.

Flash
Once each turn, you may cast a spell without paying its mana cost. If you do, at the beginning of your next upkeep, you lose the game unless you pay that spell's mana cost.

Prevent all combat damage that would be dealt to and dealt by Bereaved Aristocrat.
Unveil {2}{W}{U} ({2}{W}{U}: Transform this. Unveil only as a sorcery.)

You may have Better Half enter as a copy of any creature on the battlefield, except it's a Reflection in addition to its other creature types and it has distorted. (It can be blocked by tapped creatures but not untapped creatures.)

When Bind the Mind enters, each poisoned opponent reveals their hand. Then choose a nonland card name.
Spells with the chosen name can't be cast.

Create a 1/1 blue Bird creature token with flying. (Cast a copy of this spell once while this creature is on the battlefield.)

When Blinding Fiddler enters, until your next turn, creatures can't attack you or a planeswalker you control unless their controller pays {2} for each of those creatures.
Unveil {3}{W}{U} ({3}{W}{U}: Transform this. Unveil only as a sorcery.)

Whenever a creature you control deals combat damage to a player or planeswalker, you may pay {W} and/or {U}. When you pay {W} this way, put a +1/+1 counter on target creature you control. When you pay {U} this way, draw a card.

Flash
Flying
When Bruna, Shepherd of Souls enters, exile target noncreature spell. Then exile its controller's graveyard.

Flash
When Caronas, Eon Wanderer enters, you gain 2 life and draw two cards if Caronas, Eon Wanderer isn't on the battlefield.
{2}{W}{U}, Discard two cards: Aetherize Caronas. (To aetherize, create a token that's a copy of it, then exile that token.)

Flash
Return another artifact, creature, or enchantment you control to its owner's hand: Caylin Whirlwind gets +3/+3 until end of turn. Activate only once each turn.