Jet Medallion

Black spells you cast cost {1} less to cast.

Swamp

Ophiomancer

At the beginning of each upkeep, if you control no Snakes, create a 1/1 black Snake creature token with deathtouch.

Syr Konrad, the Grim

Whenever another creature dies, or a creature card is put into a graveyard from anywhere other than the battlefield, or a creature card leaves your graveyard, Syr Konrad deals 1 damage to each opponent.
{1}{B}: Each player mills a card. (They each put the top card of their library into their graveyard.)

Toxic Deluge

As an additional cost to cast this spell, pay X life.
All creatures get -X/-X until end of turn.

The Darkness Crystal

Black spells you cast cost {1} less to cast.
If a nontoken creature an opponent controls would die, instead exile it and you gain 2 life.
{4}{B}{B}, {T}: Put target creature card exiled with The Darkness Crystal onto the battlefield tapped under your control with two additional +1/+1 counters on it.

Plaguecrafter

When this creature enters, each player sacrifices a creature or planeswalker of their choice. Each player who can't discards a card.

Bontu's Monument

Black creature spells you cast cost {1} less to cast.
Whenever you cast a creature spell, each opponent loses 1 life and you gain 1 life.

Reassembling Skeleton

{1}{B}: Return this card from your graveyard to the battlefield tapped.

Venom, Eddie Brock

Menace (This creature can't be blocked except by two or more creatures.)
Whenever another creature dies, put a +1/+1 counter on Venom. If that creature was a Villain, draw a card.

Pitiless Plunderer

Whenever another creature you control dies, create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Sheoldred's Edict

Choose one —
• Each opponent sacrifices a nontoken creature of their choice.
• Each opponent sacrifices a creature token of their choice.
• Each opponent sacrifices a planeswalker of their choice.

Morbid Opportunist

Whenever one or more other creatures die, draw a card. This ability triggers only once each turn.

Feed the Swarm

Destroy target creature or enchantment an opponent controls. You lose life equal to that permanent's mana value.

Symbiote Spawn

When this creature dies, each opponent loses 2 life and you gain 2 life.

Scorpion, Seething Striker

Deathtouch
At the beginning of your end step, if a creature died this turn, target creature you control connives. (Draw a card, then discard a card. If you discarded a nonland card, put a +1/+1 counter on that creature.)

Skullclamp

Equipped creature gets +1/-1.
Whenever equipped creature dies, draw two cards.
Equip {1}

Six-Sided Die

Choose target creature. Roll a six-sided die.
1 — It has base toughness 1 until end of turn.
2 — Put two -1/-1 counters on it.
3 — Six-Sided Die deals 3 damage to it and you gain 3 life.
4 — It gets -4/-4 until end of turn.
5 — Destroy it.
6 — Exile it.

Liliana, Dreadhorde General

Whenever a creature you control dies, draw a card.
+1: Create a 2/2 black Zombie creature token.
−4: Each player sacrifices two creatures of their choice.
−9: Each opponent chooses a permanent they control of each permanent type and sacrifices the rest.

Dark Ritual

Grave Pact

Whenever a creature you control dies, each other player sacrifices a creature of their choice.

Braids, Arisen Nightmare

At the beginning of your end step, you may sacrifice an artifact, creature, enchantment, land, or planeswalker. If you do, each opponent may sacrifice a permanent of their choice that shares a card type with it. For each opponent who doesn't, that player loses 2 life and you draw a card.

Bojuka Bog

This land enters tapped.
When this land enters, exile target player's graveyard.
{T}: Add {B}.

Fleshbag Marauder

When this creature enters, each player sacrifices a creature of their choice.

Tombstone, Career Criminal

When Tombstone enters, return target Villain card from your graveyard to your hand.
Villain spells you cast cost {1} less to cast.

Solemn Simulacrum

When this creature enters, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
When this creature dies, you may draw a card.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control. It can attack and {T} no matter when it came under your control.)
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)