msem-instigator

Sacrifice a creature: Each opponent loses 1 life and you gain 1 life.
Sacrifice two creatures: Draw a card.
Sacrifice three creatures: Exile target creature or planeswalker.

Whenever Shina Taiyohata or another creature you control enters, you may have that creature gain haste. If you do, return that creature from the battlefield to its owner's hand at the beginning of the next end step.

First strike
Whenever Guardian of the Eclipse attacks, you may exile another target attacking creature you control, then return it to the battlefield under your control tapped and attacking.

({T}: Add {W} or {U}.)
As Ruptured Square enters, you may pay {1}. If you don't, Ruptured Square enters tapped.

Ferocious — When Volcanic Whelp enters, if you control a creature with power 4 or greater, Volcanic Whelp gets +3/+0 and gains haste until end of turn.

Choose target creature you control, then choose two —
• Put a +1/+1 counter on it.
• Put a lifelink counter on it.
• That creature gains indestructible until end of turn.

Flash
When Scuripi Lookout enters, target creature gains hexproof until end of turn.
Whenever one or more creatures you control attack, you may return Scuripi Lookout to its owner's hand.

First strike
Sacrifice this creature: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Counter three target spells.

Lifelink
Art of war — At the beginning of your end step, if Takaki's Kihei dealt damage to an opponent this turn, untap target creature you control.

Frilled Hydra enters with X +1/+1 counters on it.
Defiance (Whenever this creature takes damage, if it survives and wasn't defiant, put a +1/+1 counter on it and it becomes defiant.)
Frilled Hydra has hexproof as long as it's defiant.

Whenever Desperate Thief deals combat damage to a player, you may pay 2 life. If you do, draw a card.

Flash
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.)

Look at the top two cards of your library. Put one of them into your hand and the other into your graveyard.
Flashback {2}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Up to two target creatures each get -3/-0 until end of turn. Tap those creatures. They don't untap during their controller's next untap step.

Harmony — Draw a card.
When Enthralling Actor enters, harmonize. (Trigger up to one harmony of one permanent you control.)

Search your library for a land card, put it onto the battlefield tapped, then shuffle.
Spell mastery — If there are two or more instant and/or sorcery cards in your graveyard, untap that land.

{T}, Pay 1 life: Add {G} or {U}.
{2}, {T}, Sacrifice Alchemist's Laboratory and another permanent: Draw a card. Activate only during your turn.

{1}, Sacrifice Gasoline Canister: It deals 1 damage to any target. If a creature or planeswalker dealt damage this way would die this turn, exile it instead.

When Skeletal Shredwing enters, target creature can't block this turn.
Revive {5}{R} ({5}{R}, Exile this card from your graveyard: Create a token that's a copy of it except it has no mana cost. Revive only as a sorcery.)

Flying
Clerics you control are Angels in addition to their other types.
Attacking Angels you control get +1/+0.

Whenever Fated Mariner attacks, forebode. (Create a tapped colorless Omen artifact token with “{T}, Discard a card, Sacrifice this artifact: Draw a card.”)
{1}{U}: Fated Mariner can't be blocked this turn.

Whenever one or more creatures you control attack, you may put a progress counter on Battlesuit Prototyping.
[progress 2-6] Creatures you control get +1/+1.
[progress 7+] Creatures you control get +2/+2 and have indestructible.
Creatures you control get +2/+2 and have indestructible.

Flash
When Aethermancer's Familiar enters, at the beginning of the next end step, you may aetherize target creature you control. (To aetherize, create a token that's a copy of it, then exile that token.)