Have

Overwhelming Remorse

This spell costs {1} less to cast for each creature card in your graveyard.
Exile target creature or planeswalker.

Viscera Seer

Sacrifice a creature: Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Kaya's Ghostform

Enchant creature or planeswalker you control
When enchanted permanent dies or is put into exile, return that card to the battlefield under your control.

Feign Death

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."

Gavony Unhallowed

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

Elderfang Disciple

When this creature enters, each opponent discards a card.

Fleshbag Marauder

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

Swamp

Elvish Doomsayer

When this creature dies, each opponent discards a card.

Gravedigger

When this creature enters, you may return target creature card from your graveyard to your hand.

Soldevi Adnate

{T}, Sacrifice a black or artifact creature: Add an amount of {B} equal to the sacrificed creature's mana value.

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice this artifact: Draw a card.

Carrion Feeder

This creature can't block.
Sacrifice a creature: Put a +1/+1 counter on this creature.

Defile

Target creature gets -1/-1 until end of turn for each Swamp you control.

Nausea

All creatures get -1/-1 until end of turn.

Blood Pet

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.)

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Street Wraith

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
Cycling—Pay 2 life. (Pay 2 life, Discard this card: Draw a card.)

Feed the Swarm

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

Gibbering Barricade

Defender
{2}{B}, Sacrifice a creature: You gain 1 life and draw a card.

Demon's Disciple

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

Phyrexian Vivisector

Whenever a creature you control dies, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Chain Devil

Animate Chains — When this creature enters, each player sacrifices a nontoken creature of their choice.

Gonti, Lord of Luxury

Deathtouch
When Gonti enters, look at the top four cards of target opponent's library, exile one of them face down, then put the rest on the bottom of that library in a random order. You may cast that card for as long as it remains exiled, and mana of any type can be spent to cast that spell.

Mortician Beetle

Whenever a player sacrifices a creature, you may put a +1/+1 counter on this creature.

Virus Beetle

Unearth

Return target creature card with mana value 3 or less from your graveyard to the battlefield.
Cycling {2} ({2}, Discard this card: Draw a card.)

Demonic Gifts

Until end of turn, target creature gets +2/+0 and gains "When this creature dies, return it to the battlefield under its owner's control."

Reaping the Graves

Return target creature card from your graveyard to your hand.
Storm (When you cast this spell, copy it for each spell cast before it this turn. You may choose new targets for the copies.)

Desert of the Glorified

This land enters tapped.
{T}: Add {B}.
Cycling {1}{B} ({1}{B}, Discard this card: Draw a card.)

Dusk Legion Zealot

When this creature enters, you draw a card and you lose 1 life.

Polluted Mire

This land enters tapped.
{T}: Add {B}.
Cycling {2} ({2}, Discard this card: Draw a card.)

Underdark Explorer

Menace (This creature can't be blocked except by two or more creatures.)
When this creature enters, you take the initiative.

Dark Ritual

Return to Action

Until end of turn, target creature gets +1/+0 and gains lifelink and "When this creature dies, return it to the battlefield tapped under its owner's control."

Culling the Weak

As an additional cost to cast this spell, sacrifice a creature.
Add {B}{B}{B}{B}.

Barren Moor

This land enters tapped.
{T}: Add {B}.
Cycling {B} ({B}, Discard this card: Draw a card.)

Village Rites

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

Fake Your Own Death

Until end of turn, target creature gets +2/+0 and gains "When this creature dies, return it to the battlefield tapped under its owner's control and you create a Treasure token." (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Quicksand

{T}: Add {C}.
{T}, Sacrifice this land: Target attacking creature without flying gets -1/-2 until end of turn.

Darkness

Prevent all combat damage that would be dealt this turn.

Tragic Slip

Target creature gets -1/-1 until end of turn.
Morbid — That creature gets -13/-13 until end of turn instead if a creature died this turn.

Festergloom

Nonblack creatures get -1/-1 until end of turn.

Bloodthrone Vampire

Sacrifice a creature: This creature gets +2/+2 until end of turn.

Altar's Reap

Thorn of the Black Rose

Deathtouch
When this creature enters, you become the monarch.

Voracious Vermin

When this creature enters, create a 1/1 black Rat creature token with "This token can't block."
Whenever another creature you control dies, put a +1/+1 counter on this creature.

Supernatural Stamina

Until end of turn, target creature gets +2/+0 and gains "When this creature dies, return it to the battlefield tapped under its owner's control."

Nezumi Informant

Syphon Mind

Each other player discards a card. You draw a card for each card discarded this way.

Falkenrath Noble

Flying
Whenever this creature or another creature dies, target player loses 1 life and you gain 1 life.

Crypt Rats

{X}: This creature deals X damage to each creature and each player. Spend only black mana on X.

Deadly Dispute

As an additional cost to cast this spell, sacrifice an artifact or creature.
Draw two cards and create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Blight-Breath Catoblepas

When this creature enters, target creature an opponent controls gets -X/-X until end of turn, where X is your devotion to black. (Each {B} in the mana costs of permanents you control counts toward your devotion to black.)

Burglar Rat

Abyssal Gatekeeper

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

Ashnod's Altar

Drown in Sorrow

All creatures get -2/-2 until end of turn. Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Bloodflow Connoisseur

Sacrifice a creature: Put a +1/+1 counter on this creature.

Corrupted Conviction

Don't Have

Deathgreeter

Whenever another creature dies, you may gain 1 life.

Ashnod's Intervention

Until end of turn, target creature gets +2/+0 and gains "When this creature dies or is put into exile from the battlefield, return it to its owner's hand."

Pit Keeper

When this creature enters, if you have four or more creature cards in your graveyard, you may return target creature card from your graveyard to your hand.

Gurmag Angler

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)

Seekers' Squire

When this creature enters, it explores. (Reveal the top card of your library. Put that card into your hand if it's a land. Otherwise, put a +1/+1 counter on this creature, then put the card back or put it into your graveyard.)

Lotleth Giant

Undergrowth — When this creature enters, it deals 1 damage to target opponent for each creature card in your graveyard.

Warteye Witch

Whenever this creature or another creature you control dies, scry 1.

Undying Malice

Cast Down

Gray Merchant of Asphodel

When this creature enters, each opponent loses X life, where X is your devotion to black. You gain life equal to the life lost this way. (Each {B} in the mana costs of permanents you control counts toward your devotion to black.)

Pestilence

At the beginning of the end step, if no creatures are on the battlefield, sacrifice this enchantment.
{B}: This enchantment deals 1 damage to each creature and each player.

Charcoal Diamond

This artifact enters tapped.
{T}: Add {B}.

Plagued Rusalka

{B}, Sacrifice a creature: Target creature gets -1/-1 until end of turn.

Bojuka Bog

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

Cabal Ritual

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

Gixian Infiltrator

Whenever you sacrifice another permanent, put a +1/+1 counter on this creature.

Skulltap

Not Dead After All

Until end of turn, target creature you control gains "When this creature dies, return it to the battlefield tapped under its owner's control, then create a Wicked Role token attached to it." (Enchanted creature gets +1/+1. When this token is put into a graveyard, each opponent loses 1 life.)

Abnormal Endurance

Nasty End

As an additional cost to cast this spell, sacrifice a creature.
Draw two cards. If the sacrificed creature was legendary, draw three cards instead.

Ghastly Demise

Destroy target nonblack creature if its toughness is less than or equal to the number of cards in your graveyard.

Cruel Grimnarch

Deathtouch
When this creature enters, each opponent discards a card. For each opponent who can't, you gain 4 life.

Vicious Battlerager

When this creature enters, you take the initiative.
Spiked Retribution — Whenever this creature becomes blocked by a creature, that creature's controller loses 5 life.

Tortured Existence

{B}, Discard a creature card: Return target creature card from your graveyard to your hand.

The Dross Pits

This land enters tapped.
{T}: Add {B}.
{1}{B}, {T}, Sacrifice this land: Draw a card.