msem-instigator

Whenever Mortified Medium or another creature enters, you gain 1 life.
As long as you have at least 10 life more than your starting life total, Mortified Medium gets +4/+4 and has flying.

Target creature gets -3/-3 until end of turn. If you control a legendary creature, instead destroy that creature.

Whenever a creature you control dies, Insidious Terror gets +1/+0 and gains menace until end of turn.

Foretell {4}{R}{R} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)
Each player sacrifices four lands. A Kingdom Burns deals 4 damage to each creature and each planeswalker.

You have hexproof.
Creatures you don't control have base power and toughness 1/1 and lose all abilities.
Nonbasic lands you don't control don't untap during their controller's untap step.

Flying (This creature can't be blocked except by creatures with flying or reach.)
Escorted Rider gets +1/+1 as long as you control another creature with flying.

At the beginning of your end step, if there are three or more creature cards in your graveyard, put a +1/+1 counter on target creature you control.

Up to four target creatures gain winnow until end of turn. (Damage dealt to a creature with winnow also causes its controller to lose that much life.)

Flying, haste
Whenever a nonbasic land becomes tapped, it deals 2 damage to its controller.
Whenever Kaor Awoken attacks, it gets +1/+0 until end of turn for each other Dragon you control.

When Nomadic Patriarch enters, nourish 1. (To nourish 1, either put a +1/+1 counter on this creature or create a 1/1 white Citizen creature token.)
Remove a +1/+1 counter from Nomadic Patriarch: Put a +1/+1 counter on each other creature token you control.

Lifelink
If you would gain life, you may put that many +1/+1 counters on another creature you control instead.

Enchant opponent
Creatures enchanted player controls get -2/-2.
Whenever enchanted player casts a noncreature spell, they lose 2 life and you gain 2 life.

Harmony — You may pay {1}{G}. If you do, create a 3/3 green Beast creature token.
When Wildheart Chorister enters, harmonize. (Trigger up to one harmony of a permanent you control.)

Enchant creature
When Dark Desire enters, target player discards a card.
Whenever enchanted creature deals combat damage to a player, you draw a card and you lose 1 life.

Trample
When this creature enters, it seeks secrets or valor. (Give it that Oath Aura. Fulfill secrets by attacking with it and two or more other creatures to draw a card. Fulfill valor by dealing combat damage to a player to create a 2/1 white Soldier token.)

When Ghoulcaller's Graf enters, mill two cards.
{T}: Add {C}.
{5}, {T}, Sacrifice Ghoulcaller's Graf: Return up to two target creature cards from your graveyard to your hand.

Choose one —
• You draw two cards and you lose 2 life.
• Target player discards two cards and you gain 2 life.

Unbound Spirit can't be blocked.
When you attain Unbound Spirit, tap target creature. That creature doesn't untap during its controller's next untap step.

Whenever you cast an instant or sorcery spell from exile, copy it. You may choose new targets for the copy.

Enchant opponent
At the beginning of enchanted player's upkeep, you create a 3/2 green Crocodile creature token with trample if enchanted player has 10 or less life. Otherwise, they lose 2 life.

{T}, Exert Weary Border Guard: Tap target creature. (An exerted creature won't untap during your next untap step.)

At the beginning of your upkeep, discard a card and create a Vial token. (It's an artifact with “{1}, Sacrifice this and another permanent: Draw a card. Activate only during your turn.”)

Whenever an opponent casts a spell from a graveyard or without paying its mana cost, Piriman Stones deals 5 damage to them.

Whenever you cast a black spell, you lose 1 life.

This spell has flash as long as you control a Monk.
When Ssytai enters, return target spell or creature you don't control to its owner's hand.