msem-instigator

When Overwhelming Paperwork enters or is put into a graveyard from the battlefield, return up to one target creature to its owner's hand.
{3}{U}{U}: Sacrifice Overwhelming Paperwork. Activate only as a sorcery.

When Pale Night Remnants enters, return up to one target nonland permanent and all other permanents with the same name as that permanent to their owners' hands.

Whenever Perfecting Forgemaster enters or attacks, you may sacrifice an artifact. If you do, look at the top six cards of your library. You may reveal an Equipment card from among them. Put it onto the battlefield if its mana value is less than or equal to the sacrificed artifact's mana value. Otherwise, put it into your hand. Then shuffle.

Voracious 1 (As this enters, you may sacrifice an artifact or creature. If you do, it enters with a +1/+1 counter on it.)
Haste

Petty Destruction can't be countered.
Destroy target nonbasic permanent.

Double strike, menace
{R}{W}, Exile Picturesque Champion from your graveyard: Target creature you control gains double strike and menace until end of turn. Activate only as a sorcery.

When Pious Warden enters, choose one —
• Exile target creature you don't control until Pious Warden leaves the battlefield.
• Destroy target enchantment.
• You gain 5 life.

Destroy target creature. Mill two cards.

When Poisonous Growth enters, create a 1/1 green Saproling creature token, then attach Poisonous Growth to it.
Equipped creature has deathtouch.
Equip {4}

When Presence of the Unknown enters, you may sacrifice a creature. When you do, exile target nonland permanent.
Whenever a creature you control dies, each opponent loses 1 life and you gain 1 life.

Flying
Whenever a creature you control attacks alone, choose one —
• Exile target creature with power less than that creature's power.
• Put two +1/+1 counters on that creature.
• That creature gains first strike and lifelink until end of turn. Untap it.

Flash
Flying
When Protector of the City enters, choose target nonland permanent. Counter all activated abilities from that source and it can't attack, block, or activate abilities until Protector of the City leaves the battlefield.

{R}, {T}, Exert Provoker of Mountains: Create an X/X red Elemental creature token, where X is the number of spells you've cast this turn. (An exerted creature won't untap during your next untap step.)
{X}{X}{R}, {T}, Sacrifice Provoker of Mountains: Provoker of Mountains deals X damage to any target.

Flash
Voracious 2 (As this enters, you may sacrifice up to two artifacts and/or creatures. This creature enters with that many +1/+1 counters on it.)

Trample
When Reckless Exemplar attacks, if its power is greater than its base power, target creature an opponent controls can't block this turn.

When Recognification Process enters and at the beginning of your upkeep, create a token that's a copy of target artifact you control, then sacrifice an artifact.

Flash
Creatures your opponents control have base power and toughness 1/1.
Fleeting {1}{W}{W} (You may cast this spell for its fleeting cost. If you do, sacrifice it at the beginning of the next end step.)

Choose up to two target permanent cards in your graveyard with total mana value 4 or less. Return one to the battlefield and the rest to your hand.

{2}, Sacrifice Research Aquarium: Draw a card.
When Research Aquarium is put into a graveyard from the battlefield, investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

{1}: Exile target card from a graveyard.
At the beginning of combat on your turn, if there are three or more card types among cards exiled with Respectful Tracker, put a +1/+1 counter on target creature you control.

Choose one —
• Destroy target nonland permanent with mana value less than or equal to the number of card types among cards in your graveyard.
• Return to the battlefield target creature card from your graveyard with mana value less than or equal to the number of card types among permanents you control.

When Restless Explorer enters, search your library for a land card, reveal it, put it into your hand, then shuffle.

Counter target spell.
You may draw four cards. If you do, skip your next turn.

You may cast this spell as though it had flash by sacrificing a creature in addition to its other costs.
Destroy up to four target tapped creatures.