msem-instigator

Search your library for two basic land cards and put them onto the battlefield tapped. Then they become 0/1 green Plant creatures with “This creature can't block” in addition to their other colors, types, and abilities.

As Straw Simulacrum enters, choose a creature type.
Straw Simulacrum is the chosen creature type in addition to its other types.
Other creatures you control of the chosen type get +1/+1.

Whenever Strict Instructor attacks, harmonize. (Trigger up to one harmony of a permanent you control.)
Harmony — Tap or untap another target permanent.

Whenever Study Sphere or another artifact or enchantment you control enters, rouse 1. (Put a +1/+1 counter on a permanent you control. If it isn't a creature, tap it and it becomes a 0/0 creature in addition to its other types.)

Subway Shambler can't be blocked by creatures with lesser power.
At the beginning of each end step, if you're horrific, put a +1/+1 counter on Subway Shambler. (You're horrific as long as you've sacrificed a permanent or discarded a card this turn.)

Sunken Homestead enters tapped.
{T}: Add {B}.
{2}{B}: Until end of turn, Sunken Homestead becomes a 2/2 Zombie creature with “When this creature dies, return it to the battlefield.” Activate only if you're horrific.

Whenever you cast a spell, harmonize. (Trigger up to one harmony of a permanent you control.)
Harmony — Target permanent you control becomes a 2/2 creature with flying in addition to its other types until end of turn.

At the beginning of each end step, create X 1/1 white Spirit creature tokens with flying, where X is the number of nontoken creatures that died this turn.

Synchronous Battle Armor and equipped creature get +1/+1 for each artifact you control.
Whenever equipped creature attacks, tap up to three target creatures.
Reconfigure {3}{U}{U} ({3}{U}{U}: Attach to target creature you control; or unattach from a creature. Reconfigure only as a sorcery. While attached, this isn't a creature.)

When Syncretic Master enters, look at the top X cards of your library, where X is the number of basic land types among lands you control. Put one them into your hand and the rest into your graveyard.

When Temur Falconer enters, create a 1/1 blue Bird creature token with flying.
Whenever a creature you control with flying deals combat damage to a player or planeswalker, put a +1/+1 counter on Temur Falconer.

Trample
Whenever a creature you don't control dies, you gain 2 life.
Whenever you gain life, put that many +1/+1 counters on target creature you control.

Whenever The Pyleas, Siona's Pride enters or attacks, look at the top six cards of your library. You may reveal a legendary non-Vehicle card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.
Crew 2

Trample
When The Shepherd of Nowhere enters, each player sacrifices each other nontoken creature they control.
Whenever another nontoken creature you control dies, create a token that's a copy of that creature.

Deathtouch
When The Terror of Shady Cove enters, target opponent sacrifices an artifact. If they can't, create a 3/3 green Slug creature token with deathtouch. Then repeat this process for an enchantment and a nonbasic land.

When Thorn Tender enters, rouse 1, then put a +1/+1 counter on each creature you control. (Put a +1/+1 counter on a permanent you control. If it isn't a creature, tap it and it becomes a 0/0 creature in addition to its other types.)

Whenever you draw a card, you may have target opponent exile the top card of their library face down.
You may look at and play cards exiled with Thought Siphon, and you may spend blue mana as though it were mana of any color to cast them.

Return target creature card from your graveyard to the battlefield, then destroy target creature an opponent controls that doesn't share a creature type with it.

Target player gets a poison counter.
Draw a card.

Rouse 2. Target permanent you controls fights target creature you don't control if both are creatures. (Distribute two +1/+1 counters among permanents you control. If they aren't creatures, tap them and they become 0/0 creatures in addition to their other types.)

Land creatures you control get +1/+1 and have vigilance.
Enchantment creatures you control get +1/+1 and have lifelink.
Artifact creatures you control get +1/+1 and have flying.

When Treacherous Warden enters, search your library for a card, put into your graveyard, then shuffle.
Whenever a creature enters from your graveyard, each opponent loses 2 life and you gain 2 life.

Whenever Twilight Dancer attacks, harmonize. (Trigger up to one harmony of a permanent you control.)
Harmony — Each player loses 1 life and mills a card.

Unending Slime enters with X +1/+1 counters on it.
{2}{G}{G}{G}: Return Unending Slime from your graveyard to your hand.

This spell costs {2} less to cast if your starting deck contained at least forty cards more than the minimum deck size.
When Unrivaled Fireweaver enters, you may exile a red instant or sorcery card you own from outside the game. Until the end of your next turn, you may play that card.