msem-instigator

Flash
When Decisive Arcanist enters, you may cast target modal instant or sorcery card in your graveyard. Exile that card instead of putting it into your graveyard as it resolves.

When Trench Breaker enters, put target creature on top of its owner's library.

Towering Inferno deals X damage to each creature without flying. If a creature you don't control dealt damage this way would die this turn, exile it instead.

Vigilance, haste
All creatures able to block Jormir, Who Encircles All do so.
Jormir, Who Encircles All can block any number of creatures.

Destroy all creatures that aren't enchanted.

When Grave Reaper enters, if it wasn't cast from your hand, it gets +1/+1 until end of turn.
Unearth {B} ({B}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the end step or if it would leave the battlefield. Unearth only as a sorcery.)

Flash
Enchant player
When Curse of Doubt enters, counter target spell enchanted player controls unless they pay {2}.
{4}{U}: Enchanted player mills three cards.

When Wilting Waif dies, each opponent discards a card at random and you scry 1. (To scry 1, look at the top card of your library. You may put that card on the bottom of your library.)

Create three 1/1 white Soldier creature tokens.

Create two 1/1 red Elemental creature tokens.

Whenever you foretell a card or cast a foretold spell, you draw a card and you lose 2 life.

First strike
Whenever The Heart-hardened or another creature you control dies, each opponent loses 1 life. If this is the third time this ability has resolved this turn, you draw three cards and you lose 3 life.

When Sandbluff Enforcers enters, detain target creature an opponent controls. (Until your next turn, that creature can't attack or block and its activated abilities can't be activated.)

Double the number of each kind of counter on any number of target permanents.

Determined Chevalier has vigilance as long as it's embattled. (A creature is embattled if it has a counter on it or a permanent you control attached to it.)

As Approach the Dark Tomb enters, choose life or death.
• Life — Whenever you cast a creature spell, you may pay 1 life. If you do, draw a card.
• Death — Whenever a creature you control dies, you may pay 1 life. If you do, draw a card.

Flying
Whenever you cast a creature spell for the first time each turn, create a 1/1 green Insect creature token.

Anran's Realm enters tapped.
{T}: Add {R} or {G}.
{R}{G}, {T}: Create a Function token with “This spell can't be countered.” Activate only if you control a creature with power 4 or greater. (It's an enchantment. As you cast an instant or sorcery spell, sacrifice any number of Functions to add their effects to that spell.)

{T}, Exile a card from your graveyard: Add {B}.

Whenever a creature you control is dealt damage, it gains indestructible until end of turn. (If it survives.)

Discard a card, then draw a card.
Compose (Then if you cast this from your hand, exile it and create a Saga token with “r3—You may cast a copy of this card from exile without paying its mana cost.”)

Starting with you, each player may put a permanent card from their hand onto the battlefield. Then each player may choose a noncreature, nonland permanent. Destroy those permanents.

Whenever a creature with flying attacks you, gain control of that creature at end of combat.

Breach (Whenever this deals combat damage to a player, you may have it become an Aura Curse until your next turn. Attach it to that player.)
Whenever a cursed opponent attacks, you may draw a card.

When Mire Sculptor enters, mill three cards.
Whenever you sacrifice a permanent, you may pay {2}. If you do, return target permanent card from your graveyard to your hand.