msem-instigator

Flash
When Master of Disorientation enters, you may choose new targets for target instant or sorcery spell. Then proliferate. (Choose any number of permanents and/or players with counters on them, then give each another counter of each kind already there.)

Haste
{1}: Exile Mizujutsu Master. Return it to the battlefield under its owner's control at the beginning of the next end step.

Whenever you cast a noncreature spell, creatures you control get +1/+1 until end of turn.

Prowess
Whenever you cast your first instant or sorcery spell from your hand during each of your turns, if it doesn't have compose, it gains 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.”)

Each Merfolk and Wizard you control has “Whenever this creature attacks, abound.” (To abound, you may cast a spell that costs less than that creature from your hand without paying its mana cost.)

Prowess, haste
You may spend mana as though it were mana of any color to cast noncreature spells with mana value 3 or less.

Prowess
Whenever Siv Katari, Rebel Technician attacks, create a tapped and attacking X/X colorless Construct artifact creature token with prowess, where X is Siv Katari's power. Exile that token at end of combat.

Haste
Whenever Spellmaw Crocodile deals combat damage to a player, draw a card.
Discard a card: Spellmaw Crocodile can't be blocked this turn.

Flying, haste
When Whisperwoods Phoenix dies or you discard it, create a red enchantment token named Ash with “Whenever you cast a noncreature spell, put a feather counter on this. Then if there are three or more feather counters on it, sacrifice it and return a card named Whisperwoods Phoenix from your graveyard to the battlefield.”

When Archive Guardian enters, return target card from your graveyard to your hand.
Recite {1}{B}{G} (You may cast this creature from your graveyard for its recite cost. If you do, exile it when it enters or if it would leave the battlefield.)

When Colony Queen enters, create three 1/1 green Insect creature tokens.
Insect tokens you control have flying and deathtouch.

Deathtouch
When Crypt Strider enters, create a 1/1 black Skeleton creature token for each creature card in your graveyard.

Poisonous 2 (Whenever this creature deals combat damage to a player, that player gets two poison counters.)
Snakes you control get +1/+1 and have poisonous 1. (Multiple instances of poisonous trigger separately.)

When Gallipot Apothecary enters, create a Vial token. (It's an artifact with “{1}, Sacrifice this and another permanent: Draw a card. Activate only during your turn.”)

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
When Grave Revenant enters, target opponent loses life equal to the number of creature cards in your graveyard.

When Grim Botanist enters, create a 1/1 green Saproling creature token.
Whenever a nontoken creature you control dies, populate. (Create a token that's a copy of a creature token you control.)

{T}, Mill a card: Add {B} or {G}.
Once each turn, when a creature you control dies or a creature card is put into your graveyard from anywhere other than the battlefield, each opponent loses 1 life.

Flying, vigilance
Exile a creature card from your graveyard: Maligned Scavenger gets +1/+1 until end of turn.

First mate—Each nonland card in your starting deck has “destroy,” “die,” “graveyard,” and/or “mill” in its printed rules text. (If this card outside the game is your chosen first mate, you may swap it with a card in your opening hand.)
Deathtouch
When Marisa enters, if it was cast, you may put target permanent card from a graveyard onto the battlefield under your control.

Whenever another creature you control dies, put a +1/+1 counter on Marshy Marauder.
When Marshy Marauder dies, create a 1/1 green Insect creature token for each counter on it.

Pay 1 life, Exile a card from your graveyard: Piruz's Knight gets +2/+2 until end of turn. Activate this ability only once each turn.

{B}{G}, {T}, Remove a -1/-1 counter from a creature you control: Create a 1/1 green Elf Druid creature token.

Pungent Beetle enters with a +1/+1 counter on it for each creature you controlled that died this turn.

Whenever a player casts a creature spell, they sacrifice a creature.
Revive—{3}{B}{G}, Sacrifice a creature. ({3}{B}{G}, Sacrifice a creature, Exile this card from your graveyard: Create a token that's a copy of it except it has no mana cost. Revive only as a sorcery.)

{2}{B/G}: Return Silthway Scuttler from your graveyard to your hand.
{2}{B/G}, Exile Silthway Scuttler from your graveyard: Put two +1/+1 counters on target creature.