msem-instigator

Whenever Halford enters or attacks, an opponent chooses one. When they choose one that has already been chosen, copy that ability.
• That opponent loses 2 life and you gain 2 life.
• That opponent sacrifices a permanent.
• That opponent discards a card. If they can't, draw a card.

Destroy target creature or planeswalker. If a planeswalker is destroyed this way, search its owner's graveyard, hand, and library for any number of cards with the same name as that card and exile them. Then that player shuffles.

Return target creature card from your graveyard to the battlefield. If you control a Demon, each opponent loses 3 life.

Gangling Titan has menace and deathtouch as long as there are four or more card types among cards in your graveyard.

Target creature gets -1/-1 until end of turn. Create a 1/1 green Saproling creature token.

When Forgotten Wretch enters, you may sacrifice another creature. If you do, draw a card.

{B}, {T}: Exile target creature card from a graveyard. You gain 2 life.
{1}{B}, {T}: Mill three cards. You lose 2 life.
{3}{B}{B}, {T}, Sacrifice Ethics and Reanimation: Return target creature card from your graveyard to the battlefield. Activate only as a sorcery.

Ward—Sacrifice three permanents.
At the beginning of your end step, put a desperation counter on End of History. Draw two cards for each counter on it, then exile the top three cards of your library for each counter on it.

Enchant creature
Enchanted creature gets -3/-3.

Choose one or both —
• Destroy target creature with mana value 1 or less.
• Each player discards a card.

Whenever a creature you control dies, put a loyalty counter on Dias, Freed from Belief.
[0]: Create a 2/1 black Nightmare creature token with “This creature can't block.”
[–X]: Destroy target creature or planeswalker unless an opponent pays twice X life.

Haste
Fleeting {B} (You may cast this spell for its fleeting cost. If you do, sacrifice it at the beginning of the next end step.)

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

When Decrepit Hero dies, create a 2/2 black Soldier creature token.
Fleeting {1}{B} (You may cast this spell for its fleeting cost. If you do, sacrifice it at the beginning of the next end step.)

Each creature can't have power greater than its base power and can't have toughness greater than its base toughness.

This spell costs {1} less to cast for each card type among cards in your graveyard.
Deathtouch

Each player sacrifices a creature. Then return a creature card with mana value 3 or less from your graveyard to the battlefield.

{T}, Exert Bestower of Princely Sin: You may sacrifice another creature. If you do, target opponent may sacrifice a permanent that shares a card type with it. If they don't, that player loses 1 life and you draw a card. Repeat this process for artifact, enchantment, land, and planeswalker. Activate only as a sorcery.

Flying
When Battlefront Scavenger enters, return target creature card with mana value 3 or less from your graveyard to your hand.

Flying, deathtouch

When Asking Imp enters, an opponent may pay 2 life. If they do, return Asking Imp to its owner's hand.

Whenever an artifact you control enters or is put into a graveyard from the battlefield, Workshop Engineer gets +1/+1 until end of turn.

When Warping Relic enters or is put into a graveyard from the battlefield, choose one —
• Draw two cards, then discard a card.
• Return another target nonland permanent to its owner's hand.
• Choose any number of target creatures. Switch their power and toughness until end of turn.

Defender
Whenever one or more creatures you control deal combat damage to a player, surveil 1. (Look at the top card of your library. You may put that card into your graveyard.)
When Wall of Notes dies, draw a card.

Whenever you cast your second spell each turn, create a 1/1 blue Jellyfish Spirit creature token with flying.