Demonlord of Ashmouth

Flying
When this creature enters, exile it unless you sacrifice another creature.
Undying (When this creature dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)

Power Conduit

{T}, Remove a counter from a permanent you control: Choose one —
• Put a charge counter on target artifact.
• Put a +1/+1 counter on target creature.

Mana Geyser

Add {R} for each tapped land your opponents control.

Vengeful Vampire

Flying
Undying (When this creature dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)

Morbid Opportunist

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

Acolyte of Aclazotz

{T}, Sacrifice another creature or artifact: Each opponent loses 1 life and you gain 1 life.

Aether Snap

Remove all counters from all permanents and exile all tokens.

Rakdos Riteknife

Equipped creature gets +1/+0 for each blood counter on this Equipment and has "{T}, Sacrifice a creature: Put a blood counter on Rakdos Riteknife."
{B}{R}, Sacrifice this Equipment: Target player sacrifices a permanent of their choice for each blood counter on this Equipment.
Equip {2}

Soulcage Fiend

When this creature dies, each player loses 3 life.

Lyzolda, the Blood Witch

{2}, Sacrifice a creature: Lyzolda deals 2 damage to any target if the sacrificed creature was red. Draw a card if the sacrificed creature was black.

Village Rites

As an additional cost to cast this spell, sacrifice a creature.
Draw two cards.

Star of Extinction

Destroy target land. Star of Extinction deals 20 damage to each creature and each planeswalker.

Ryusei, the Falling Star

Flying
When Ryusei dies, it deals 5 damage to each creature without flying.

Mudbutton Torchrunner

When this creature dies, it deals 3 damage to any target.

Blasphemous Act

This spell costs {1} less to cast for each creature on the battlefield.
Blasphemous Act deals 13 damage to each creature.

Murder

Dragonskull Summit

This land enters tapped unless you control a Swamp or a Mountain.
{T}: Add {B} or {R}.

Chain Reaction

Chain Reaction deals X damage to each creature, where X is the number of creatures on the battlefield.

Grave Pact

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

Harvester of Souls

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
Whenever another nontoken creature dies, you may draw a card.

Hatchet Bully

{2}{R}, {T}, Put a -1/-1 counter on a creature you control: This creature deals 2 damage to any target.

Unmake

Hex Parasite

{X}{B/P}: Remove up to X counters from target permanent. For each counter removed this way, this creature gets +1/+0 until end of turn. ({B/P} can be paid with either {B} or 2 life.)

Molten Slagheap

{T}: Add {C}.
{1}, {T}: Put a storage counter on this land.
{1}, Remove X storage counters from this land: Add X mana in any combination of {B} and/or {R}.

Soul Snuffers

When this creature enters, put a -1/-1 counter on each creature.

Swamp

Darkness

Prevent all combat damage that would be dealt this turn.

Phyrexian Vault

{2}, {T}, Sacrifice a creature: Draw a card.

Screeching Buzzard

Flying
When this creature dies, each opponent discards a card.

Leechridden Swamp

({T}: Add {B}.)
This land enters tapped.
{B}, {T}: Each opponent loses 1 life. Activate only if you control two or more black permanents.

Endling

{B}: This creature gains menace until end of turn.
{B}: This creature gains deathtouch until end of turn.
{B}: This creature gains undying until end of turn. (When this creature dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)
{1}: This creature gets +1/-1 or -1/+1 until end of turn.

Kokusho, the Evening Star

Flying
When Kokusho dies, each opponent loses 5 life. You gain life equal to the life lost this way.

Butcher Ghoul

Undying (When this creature dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)

Pilgrim's Eye

Flying
When this creature enters, you may search your library for a basic land card, reveal it, put it into your hand, then shuffle.

Oversold Cemetery

At the beginning of your upkeep, if you have four or more creature cards in your graveyard, you may return target creature card from your graveyard to your hand.

Cabal Ritual

Add {B}{B}{B}.
Threshold — Add {B}{B}{B}{B}{B} instead if seven or more cards are in your graveyard.

Scavenger Drake

Flying
Whenever another creature dies, you may put a +1/+1 counter on this creature.

Din of the Fireherd

Create a 5/5 black and red Elemental creature token. Target opponent sacrifices a creature of their choice for each black creature you control, then sacrifices a land of their choice for each red creature you control.

Evernight Shade

{B}: This creature gets +1/+1 until end of turn.
Undying (When this creature dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)

Magus of the Abyss

At the beginning of each player's upkeep, destroy target nonartifact creature that player controls of their choice. It can't be regenerated.

Flayer of the Hatebound

Undying (When this creature dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)
Whenever this creature or another creature enters from your graveyard, that creature deals damage equal to its power to any target.

Hound of Griselbrand

Double strike
Undying (When this creature dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)

Bojuka Bog

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

Miren, the Moaning Well

{T}: Add {C}.
{3}, {T}, Sacrifice a creature: You gain life equal to the sacrificed creature's toughness.

Undying Malice

Until end of turn, target creature gains "When this creature dies, return it to the battlefield tapped under its owner's control with a +1/+1 counter on it."

Undying Evil

Target creature gains undying until end of turn. (When it dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)

Rakdos Carnarium

This land enters tapped.
When this land enters, return a land you control to its owner's hand.
{T}: Add {B}{R}.

Corrupted Conviction

Disturbed Burial

Buyback {3} (You may pay an additional {3} as you cast this spell. If you do, put this card into your hand as it resolves.)
Return target creature card from your graveyard to your hand.

Tumble

Tumble deals 6 damage to each creature with flying.

Rough

Rough deals 2 damage to each creature without flying.

Rough // Tumble

Mortuary Mire

This land enters tapped.
When this land enters, you may put target creature card from your graveyard on top of your library.
{T}: Add {B}.

Killing Wave

For each creature, its controller sacrifices it unless they pay X life.

Mountain

Shinka, the Bloodsoaked Keep

{T}: Add {R}.
{R}, {T}: Target legendary creature gains first strike until end of turn.

Eradicate

Exile target nonblack creature. Search its controller's graveyard, hand, and library for all cards with the same name as that creature and exile them. Then that player shuffles.

Barter in Blood

Each player sacrifices two creatures of their choice.

Nekrataal

First strike
When this creature enters, destroy target nonartifact, nonblack creature. That creature can't be regenerated.

Dark Ritual

Retribution of the Ancients

{B}, Remove X +1/+1 counters from among creatures you control: Target creature gets -X/-X until end of turn.

Temple of Malice

This land enters tapped.
When this land enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)
{T}: Add {B} or {R}.

Rakdos Signet

Shizo, Death's Storehouse

{T}: Add {B}.
{B}, {T}: Target legendary creature gains fear until end of turn. (It can't be blocked except by artifact creatures and/or black creatures.)

Terminate

Destroy target creature. It can't be regenerated.

In the Web of War

Whenever a creature you control enters, it gets +2/+0 and gains haste until end of turn.