msem-instigator

Target creature gains indestructible until end of turn. You gain 4 life.
Prophecy {G} (Once each turn, you may exile a card with prophecy as you reveal it. When you do, you may cast it for its prophecy cost as long as it's exiled.)

When Voldaren Crypt-Guard enters, create a Weapon token. (It's an Equipment artifact with “Equipped creature gets +1/+1” and equip {2}.)

Mill five cards. You may choose up to two nonland cards with mana value 2 or less milled this way. You may cast one without paying its mana cost. Put the rest into your hand.
Coalesce {6}{G}{W} (You may cast this from your graveyard for {6}{G}{W}. If you do, it enters as a Horror creature after it resolves. Exile it if it would leave the battlefield or not resolve.)
Flying, vigilance

Spells you cast with mana value 4 or greater cost {1} less to cast.

When Ch'aska Walla Captain enters, if you cast it, you may return an enchantment card from your graveyard to the battlefield. When you do, you gain life equal to that enchantment's mana value.

Lifelink
Other creatures you control enter with an additional +1/+1 counter on them.
{2}{G}{W}: Nourish 1. (To nourish 1, either put a +1/+1 counter on this creature or create a 1/1 white Citizen creature token.)

(Activate each submodule once as a sorcery. When this enters, activate one submodule for free.)
{U}{U}{U}: Premise
Create a token that's a copy of target creature.
{U}{U}{U}: Inference
Tap all creatures target player controls. Those creatures don't untap during that player's next untap step.
{U}{U}{U}: Conclusion
Logic Module gains “Whenever a creature you control deals combat damage to an opponent, you may draw a card.”

When Garrison Warden enters, put a +1/+1 counter on target creature you control.
Surpass {5}{W} ({5}{W}: Transform this. This costs {1} less to activate for each counter on it. Activate only as a sorcery.)

Put any number of target creature cards from your graveyard on top of your library. You draw two cards and you lose 2 life.

Unearthed Legion's power and toughness are each equal to the number of cards in your graveyard.
At the beginning of your upkeep, mill a card.

Flying, trample
Once during each of your turns, you may cast a spell from your graveyard without paying its mana cost.
When Yhzag, Alpha and Omega is put into a graveyard from anywhere, its owner shuffles their graveyard into their library.

Whenever another creature you control enters, you gain 1 life.

Engulf in Flames deals 1 damage to target player and each of up to three target creatures that player controls. Those creatures can't block this turn.

Destroy target nonland permanent.
If you've sacrificed a permanent this turn, draw a card.

Reach
When Risti Watchkeeper enters, rediscover a creature card. (Look at the top card of your library. You may reveal it and put it into your hand if it's a creature card. Otherwise, put it back or into your graveyard.)

Whenever you cast an enchantment spell, create a 1/1 white and black Bird creature token with flying and vigilance.
Whenever three or more creatures you control deal combat damage to a player, that player sacrifices a creature. If they can't, they discard a card.

Target opponent reveals their hand. You choose a nonland card from it. If you can't, they discard a card. Otherwise, that player discards a card, then if they didn't discard the chosen card, you create a tapped Treasure token. (It's an artifact with “{T}, Sacrifice this artifact: Add one mana of any color.”)

Flash
When Shinrin Spellhunter enters, if an opponent cast a noncreature spell this turn, draw a card.

When Ulvenwald Ranger enters, surveil 2. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)
{1}{G}: Transform Ulvenwald Ranger. Activate only if it's attacking.

({T}: Add {R} or {G}.)
As Dangerous Territory enters, you may pay {1}. If you don't, Dangerous Territory enters tapped.

{2}, {T}: Tap target creature. This ability costs {2} less to activate if you control an enchantment.

I, II — Search your library for a basic land card, reveal it, put it into your hand, then shuffle.
Discovery — {4}: You gain 2 life.

As an additional cost to cast this spell, sacrifice a creature.
Kindle the Cursed deals 3 damage to target creature and 3 damage to that creature's controller.

Menace
Cat creatures you control have menace.
When Basat Priest enters, create a 2/2 white Cat creature token.