msem-instigator

Engorge (As this enters, mill three cards, then exile a card from among the milled cards.)
When Blood Servant enters, if it engorged a creature card, you draw a card and you lose 2 life.

When Greypelt Clergy enters, choose one —
• Put a +1/+1 counter on Greypelt Clergy.
• Permutate. (You may remove a counter from a creature you control. If you do, put two +1/+1 counters on a different creature you control.)

{U}, {T}: Sacrifice any number of nontoken creatures. Create an X/X blue Horror creature token, where X is the total power of those creatures. Then if X is 4 or greater, you may transform Performer of Brilliance.

{W/B}: Kambiro, the Untrue King gets +1/+1 until end of turn.
Whenever a storied permanent you control enters, if you cast it, return target creature card from your graveyard to your hand. If that creature's power is less than Kambiro's power, you may return it to the battlefield instead. (Enchantments and legendary permanents are storied.)

When Ingredient Scroungers enters, if you control a creature with deathtouch, return target permanent card from your graveyard to your hand.

{2}, {T}, Sacrifice a creature: You draw a card and you lose 2 life.
{1}, {T}, Exile a creature card from your graveyard: You gain 2 life.

Exile target nonland permanent. For each of its colors, its controller creates a 1/1 colorless Spirit creature token.

Kanvar can't attack or block.
Whenever a creature you control with power 4 or greater dies, draw a card.
{R}{G}, {T}: Copy target triggered ability you control. You may choose new targets for the copy. (A triggered ability uses the words “when,” “whenever,” or “at.”)

When Rigid Conformist enters, for each {W} spent to cast it, create a 1/1 white Human creature token.
Each creature you control gets +2/+2 if you control another creature with the same name as that creature.

Landfall — Whenever a land you control enters, create a 5/5 green Wurm creature token with trample.

Vigilance
If you would take a combat phase or a main phase, take the other instead.
{U/B}, Pay 1 life: Untap target creature you control.

(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.)

When Ontarachie Envoy enters, nourish, then germinate. (To nourish, put a +1/+1 counter on this creature or create a 1/1 white Citizen creature token. To germinate, put a +1/+1 counter on a creature you control or create a 1/1 green Saproling creature token.)

Neckbreaker Viking gets +1/+0 and has menace as long as it's embattled. (A creature is embattled if it has a counter on it or has a permanent you control attached to it.)

You may reveal a Knight or Soldier card from your hand as you cast this spell. If you do or you control one as you cast it, you may cast it as though it had flash and it can't be countered.
Exile target nonland permanent with mana value 3 or less.

Whenever a creature you control dies, Twilight Blade deals 1 damage to each opponent and you gain 1 life.

If a triggered ability of equipped creature would trigger, it triggers an additional time.
Equip {2}

When Attuned Ancient enters, if you control a legendary creature, you may have Attuned Ancient deal damage equal to its power to target creature an opponent controls.

Whenever Rhudai Swathcutter attacks, you may search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

{T}: Add {B} or {G}. You lose 1 life unless you have less life than an opponent.

Trample
When Pernicious Primavore enters or dies, destroy up to three target artifacts and/or enchantments.

Enchant creature or planeswalker
Enchanted permanent has base power 0 and loses all abilities.

Look at the top three cards of your library. Put one of them into your hand and the rest into your graveyard.
Flashback {3}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Enchant creature
Enchanted creature gets +4/+4, has flying and first strike, and is an Angel in addition to its other types.
When enchanted creature dies, return Angelic Destiny to its owner's hand.

Enchant creature
Enchanted creature blocks each combat if able.
Whenever enchanted creature attacks, it loses flying until end of turn.