msem-instigator

When Guardian of the Wurm enters, create a 6/6 green Wurm creature token with trample.

When Hardlight Visionary enters, create a Function token with “Until end of turn, target creature becomes a 5/5 Dragon and gains flying.” (It's an enchantment. As you cast an instant or sorcery spell, sacrifice any number of Functions to add their effects to that spell.)

Flying
Once during each of your turns, for each creature you control, you may activate one of that creature's activated abilities with {T} in its cost without paying {T} and as though that creature had haste.

Granite Sibyl enters with three +1/+1 counters on it.
Whenever another creature you control enters, move a +1/+1 counter from Granite Sibyl to that creature.

Kicker {U} (You may pay an additional {U} as you cast this spell.)
Counter target spell. If this spell was kicked, look at the top three cards of your library, then put them back in any order.

Renown 1 (When this creature deals combat damage to a player, if it isn't renowned, put a +1/+1 counter on it and it becomes renowned.)
Whenever a creature you control becomes renowned, scry 1.

Voidtouched Nightblade can't block.
Simulacrum (When this creature dies, exile it from your graveyard. If you do, create a token that is a copy of it except it is a colorless 1/1 Crystal Elf Rogue artifact creature.)

This spell costs {2} less to cast if you control a Scout.
Search your library for up to two basic land cards, reveal those cards, and put one onto the battlefield tapped and the other into your hand, then shuffle.

Once each turn, when another nontoken creature is returned to your hand from the battlefield, you may create a token that's a copy of that creature.

Whenever a player discards a card, you may draw a card and put a loyalty counter on Mei Liva, the Broken.
[0]: Target permanent's controller sacrifices it unless they discard two cards.
[–1]: Each opponent loses X life and you gain X life, where X is the number of cards in your hand.
[–3]: Target player chooses a card in their hand, then discards the rest.

{X}, {T}: Search your library for a creature card with mana value X or less and no creature types noted by Memorial to Sir Jasper, put it onto the battlefield, then shuffle. Note that creature's creature types. Activate only as a sorcery.

Double strike
At the beginning of each end step, if a creature you control died this turn, Tempered Survivor deals 2 damage to each opponent.

{2}, {T}, Sacrifice Pale Morningstar Powder: Put two -1/-1 counters on target creature.

Tithe (As you cast this spell, you may tap three artifacts and/or creatures you control.)
Faradia's Outrage deals X damage to any target. If this spell's tithe was paid, it deals X damage divided as you choose among any number of targets instead.

Tap target creature. If you control a Monk, draw a card. (Then exile this card. You may cast the creature later from exile.)

Prowess
Landfall — Whenever a land you control enters, create a 1/1 green, blue, and red Elf Scout creature token with prowess.

Electrical Eradication deals 3 damage to each nonlegendary creature. Then if you controlled a red legendary creature or planeswalker as you cast this spell, it deals 3 damage to each nonlegendary creature and each opponent.

Hexproof
Rapport — Whenever Depths Stalker and at least one other creature you control become tapped, Depths Stalker gets +1/+0 until end of turn and can't be blocked this turn.

Target creature gets +2/+1 until end of turn. (Then exile this card. You may cast the creature later from exile.)

Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Enspirit (As you cast this spell, you may exile a nonenchantment creature you control until this leaves the battlefield or fails to resolve. Reduce this spell's cost by the exiled card's mana value.)
You may play any number of lands on each of your turns.

Decayed Bedchamber enters tapped.
When Decayed Bedchamber enters, look at the top card of your library. You may put it into your graveyard.
{T}: Add {B} or {G}.

[+1]: Create a 1/1 blue Elemental creature token with flying, then crystallize twice. (Put a +1/+1 counter on a creature you control or create a Treasure.)
[–3]: Exile target nonland permanent. As long as it's exiled, its owner may pay {W}{U}{B}{R}{G} as a sorcery to put it into their hand.
[–7]: You get an emblem with “Pay 1 life: Add one mana of any color.” Then you gain 100 life.

Whenever another nontoken permanent you control enters, create a Food token.
At the beginning of each end step, put X +1/+1 counters on up to one target creature, where X is the amount of life you've gained this turn.