msem-instigator

When Osseous Augur enters, target creature an opponent controls gets -1/-1 until end of turn. If that creature's controller is cursed, that creature gets -3/-3 until end of turn instead.

({T}: Add {B}.)
Wanderlust — Otherworldly Swamp enters tapped unless you control four or more other differently named lands.
{1}, {T}: Add one mana of any color.

Enchant player
At the beginning of your upkeep, enchanted player loses 1 life.

When Outside the Airlock enters, create a tapped 3/2 green Horror creature token.
Whenever a creature you control dies, each opponent loses 1 life and you gain 1 life.

Target player reveals their hand. You choose a nonland card from it. That player discards that card unless they discard three other cards.

Each player discards two cards. Then if there are four or more card types among cards in your graveyard, create two 1/1 white Human creature tokens.

Target opponent reveals their hand. You may choose a noncreature, nonland card from it. If you do, that player discards that card. Otherwise, they lose 3 life.

When P-3 Ambusher enters, you may sacrifice a creature or discard a creature card. If you do, draw a card.

Lifelink
When Pact Equivocator enters, you lose 2 life and draw a card.

Enchant creature
Enchanted creature gets +1/+1 and has flying and indestructible.
At the beginning of your upkeep, sacrifice a creature.

Enchant creature
When Paid in Blood enters, create a Treasure token. (It's an artifact with “{T}, Sacrifice this artifact: Add one mana of any color.”)
Enchanted creature gets +1/+1 and has lifelink.

{T}: Target player loses 1 life.
Whenever you cast a spell from your graveyard, untap Paincaller.

Search target player's library for a card and exile it, then that player shuffles.
Coalesce {5}{B} (You may cast this from your graveyard for {5}{B}. If you do, it enters as a Horror creature after it resolves. Exile it if it would leave the battlefield or not resolve.)

Choose target player, then choose two —
• That player loses 2 life.
• That player draws two cards.
• Put two -1/-1 counters on target creature that player controls.

You draw two cards, lose 2 life, then mill two cards.

{1}, Discard a card: Painted Watcher gets +1/+1 and becomes the color of your choice until end of turn.

Whenever a creature dies, Pakka, the Shadowcloak deals 1 damage to each opponent.

Sacrifice a creature: Pale Horse gets +2/+2 until end of turn.
Ride {B} ({B}: Transform this and attach it to target creature you control without a Steed. Ride only as a sorcery.)

When Paleolizard enters, you may discard a card. When you do, return target card from your graveyard to your hand that shares a type with that card.

When Paleontologist enters, search your library for up to two artifact and/or Skeleton cards and put them into your graveyard, then shuffle.

Return target creature card from your graveyard to the battlefield. That creature is a black Elemental in addition to its other colors and types. Upgrade it. (Give it one of the listed counters it doesn't already have.)
• +1/+1
• Flying
• Lifelink

Once during each of your turns, you may cast a legendary creature or planeswalker spell from your graveyard.
Sacrifice Pallid Herald: Exile up to three target cards from graveyards.

Flying
When Palloren Vulture enters, each player mills two cards.

Flying
Other creatures get -1/-1.
Whenever Pan Long enters or deals combat damage to a player, return to the battlefield under your control target creature card from a graveyard that was put there from the battlefield this turn.

Choose one or both—
• Target creature gets -4/-4 until end of turn.
• Return target creature card with mana value 1 from your graveyard to the battlefield.