msem-instigator

Menace
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)

Menace
Savage Stalker attacks each combat if able.

Flying, haste
Erratic (When this creature dies, reveal the top four cards of your library. Put a creature card that costs less than this revealed this way onto the battlefield and the rest on the bottom of your library in any order.)
When Splitflame Phoenix dies, you may pay {R}. If you do, return it to its owner's hand.

Haste
At the beginning of your end step, return Sunwatcher Aspirant to its owner's hand.

Defender

Reach
{T}: Yangzhi Cloudpiercer deals 1 damage to target player or planeswalker.

When Jade Empire Cartographer enters, choose one —
• 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.)
• Put a +1/+1 counter on target creature you control.

Glorious end — When Seeker of Conto Sika dies, if it was tapped, draw a card.

Each player mills five cards.
Coalesce {4}{U}{B} (You may cast this from your graveyard for {4}{U}{B}. If you do, it enters as a Horror creature after it resolves. Exile it if it would leave the battlefield or not resolve.)
Drink Thoughts Like Oil can't be blocked.

Faradia's Favored attacks each combat if able.
Whenever you pay a tithe, you may return Faradia's Favored from your graveyard to the battlefield.

Haste
When Magmatic Violator enters, target opponent sacrifices a creature.
At the beginning of the end step, sacrifice Magmatic Violator.

Haste
When Doomed Alchemist dies, create two Treasure tokens. (They're artifacts with “{T}, Sacrifice this artifact: Add one mana of any color.”)

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.”)

{2}{W}: Audacious Knight gains first strike and vigilance until end of turn. (It deals combat damage before creatures without first strike. Attacking does not cause it to tap.)

Flying (This creature can't be blocked except by creatures with flying or reach.)
Motivate 1 (When this creature enters, you may motivate target creature with less power than this by putting a +1/+1 counter on it.)

When Coalition Apothecary enters, you gain 1 life for each nonland permanent you control.

First strike

Flying
Morph {4}{W} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)
When you turn Hopebringer Cherub face up, creatures you control get +1/+1 until end of turn.

S-19 Long Jacket has first strike as long as it's attacking.
S-19 Long Jacket has lifelink as long as it's blocking.

When Third Legion Rider enters, if you control an embattled creature, tap target creature an opponent controls. It doesn't untap during its controller's next untap step. (A creature is embattled if it has a counter on it or has a permanent you control attached to it.)

Flash (You may cast this spell any time you could cast an instant.)
When Culi-Sae Transfigurer enters, switch target creature's power and toughness until end of turn.

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.)
When Soul Trapper enters, tap target creature an opponent controls. That creature doesn't untap during its controller's untap step for as long as you control Soul Trapper.

Flying

When Aminatou's Adherent enters, judge target creature you control. (Honor it by putting a +1/+1 counter on it or condemn it by sacrificing it to draw a card.)
Whenever you condemn a creature, creatures you control gain menace until end of turn.

Other Knights and Soldiers you control get +1/+0.
Cowards can't block Knights and Soldiers you control.
When Belmord Bloodcurdler enters, target creature an opponent controls becomes a Coward in addition to its other types. (This effect last indefinitely.)