Avatar of Woe

If there are ten or more creature cards total in all graveyards, this spell costs {6} less to cast.
Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)
{T}: Destroy target creature. It can't be regenerated.

It That Betrays

Annihilator 2 (Whenever this creature attacks, defending player sacrifices two permanents of their choice.)
Whenever an opponent sacrifices a nontoken permanent, put that card onto the battlefield under your control.

Diabolic Tutor

Search your library for a card, put that card into your hand, then shuffle.

Ravenous Chupacabra

When Ravenous Chupacabra enters, destroy target creature an opponent controls.

Rune-Scarred Demon

Flying
When this creature enters, search your library for a card, put it into your hand, then shuffle.

Nazgûl Battle-Mace

Equipped creature has menace, deathtouch, annihilator 1, and "Whenever an opponent sacrifices a nontoken permanent, put that card onto the battlefield under your control unless that player pays 3 life." (Whenever a creature with annihilator 1 attacks, defending player sacrifices a permanent of their choice.)
Equip {3}

Final Parting

Search your library for two cards. Put one into your hand and the other into your graveyard. Then shuffle.

Dread Return

Return target creature card from your graveyard to the battlefield.
Flashback—Sacrifice three creatures. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Tetzimoc, Primal Death

Deathtouch
{B}, Reveal Tetzimoc, Primal Death from your hand: Put a prey counter on target creature. Activate only during your turn.
When Tetzimoc enters, destroy each creature your opponents control with a prey counter on it.

Dark Ritual

Zombify

Return target creature card from your graveyard to the battlefield.

Buried Alive

Search your library for up to three creature cards, put them into your graveyard, then shuffle.

Shriekmaw

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)
When Shriekmaw enters, destroy target nonartifact, nonblack creature.
Evoke {1}{B} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)

Vile Entomber

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
When this creature enters, search your library for a card, put that card into your graveyard, then shuffle.

Champion of Stray Souls

{3}{B}{B}, {T}, Sacrifice X other creatures: Return X target creature cards from your graveyard to the battlefield.
{5}{B}{B}: Put Champion of Stray Souls on top of your library from your graveyard.

Profane Tutor

Suspend 2—{1}{B} (Rather than cast this card from your hand, pay {1}{B} and exile it with two time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost.)
Search your library for a card, put that card into your hand, then shuffle.

Blood for Bones

As an additional cost to cast this spell, sacrifice a creature.
Return a creature card from your graveyard to the battlefield, then return another creature card from your graveyard to your hand.

Fleshbag Marauder

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

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.)

Tergrid's Lantern

{T}: Target player loses 3 life unless they sacrifice a nonland permanent of their choice or discard a card.
{3}{B}: Untap Tergrid's Lantern.

Tergrid, God of Fright

Menace
Whenever an opponent sacrifices a nontoken permanent or discards a permanent card, you may put that card from a graveyard onto the battlefield under your control.

Tergrid, God of Fright // Tergrid's Lantern

Sol Ring

Diabolic Servitude

When Diabolic Servitude enters, return target creature card from your graveyard to the battlefield.
When the creature put onto the battlefield with Diabolic Servitude dies, exile it and return Diabolic Servitude to its owner's hand.
When Diabolic Servitude leaves the battlefield, exile the creature put onto the battlefield with Diabolic Servitude.

Tendrils of Corruption

Tendrils of Corruption deals X damage to target creature and you gain X life, where X is the number of Swamps you control.

Plaguecrafter

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

Gatekeeper of Malakir

Kicker {B} (You may pay an additional {B} as you cast this spell.)
When this creature enters, if it was kicked, target player sacrifices a creature of their choice.

Exhume

Each player puts a creature card from their graveyard onto the battlefield.

Crypt Ghast

Extort (Whenever you cast a spell, you may pay {W/B}. If you do, each opponent loses 1 life and you gain that much life.)
Whenever you tap a Swamp for mana, add an additional {B}.

Nuclear Fallout

Each creature gets twice -X/-X until end of turn. Each player gets X rad counters.

Victimize

Choose two target creature cards in your graveyard. Sacrifice a creature. If you do, return the chosen cards to the battlefield tapped.

Grim Tutor

Search your library for a card, put that card into your hand, then shuffle. You lose 3 life.

Persist

Return target nonlegendary creature card from your graveyard to the battlefield with a -1/-1 counter on it.

Sheoldred, Whispering One

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
At the beginning of your upkeep, return target creature card from your graveyard to the battlefield.
At the beginning of each opponent's upkeep, that player sacrifices a creature of their choice.

Pathrazer of Ulamog

Annihilator 3 (Whenever this creature attacks, defending player sacrifices three permanents of their choice.)
Pathrazer of Ulamog can't be blocked except by three or more creatures.

Phyrexian Delver

When Phyrexian Delver enters, return target creature card from your graveyard to the battlefield. You lose life equal to that card's mana value.

Black Sun's Twilight

Up to one target creature gets -X/-X until end of turn. If X is 5 or more, return a creature card with mana value X or less from your graveyard to the battlefield tapped.

Doom Blade

Abhorrent Overlord

Flying
When Abhorrent Overlord enters, create a number of 1/1 black Harpy creature tokens with flying equal to your devotion to black. (Each {B} in the mana costs of permanents you control counts toward your devotion to black.)
At the beginning of your upkeep, sacrifice a creature.

Unmarked Grave

Search your library for a nonlegendary card, put that card into your graveyard, then shuffle.

Ebon Stronghold

Ebon Stronghold enters tapped.
{T}: Add {B}.
{T}, Sacrifice Ebon Stronghold: Add {B}{B}.

Duress

Target opponent reveals their hand. You choose a noncreature, nonland card from it. That player discards that card.

Zombie Infestation

Discard two cards: Create a 2/2 black Zombie creature token.

Rescue from the Underworld

As an additional cost to cast this spell, sacrifice a creature.
Choose target creature card in your graveyard. Return that card and the sacrificed card to the battlefield under your control at the beginning of your next upkeep. Exile Rescue from the Underworld.

Blood Artist

Whenever Blood Artist or another creature dies, target player loses 1 life and you gain 1 life.

Swamp

Reanimate

Put target creature card from a graveyard onto the battlefield under your control. You lose life equal to its mana value.

Grave Betrayal

Whenever a creature you don't control dies, return it to the battlefield under your control with an additional +1/+1 counter on it at the beginning of the next end step. That creature is a black Zombie in addition to its other colors and types.

Tempt with Immortality

Tempting offer — Return a creature card from your graveyard to the battlefield. Each opponent may return a creature card from their graveyard to the battlefield. For each opponent who does, return a creature card from your graveyard to the battlefield.

Culling the Weak

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

Command the Dreadhorde

Choose any number of target creature and/or planeswalker cards in graveyards. Command the Dreadhorde deals damage to you equal to the total mana value of those cards. Put them onto the battlefield under your control.

Deathly Ride

Return target creature card from your graveyard to your hand. (Then exile this card. You may cast the creature later from exile.)

Fell Horseman

When Fell Horseman dies, put it on the bottom of its owner's library.

Fell Horseman // Deathly Ride

Rise of the Dark Realms

Put all creature cards from all graveyards onto the battlefield under your control.

Entomb

Search your library for a card, put that card into your graveyard, then shuffle.

Reassembling Skeleton

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

Doomed Necromancer

{B}, {T}, Sacrifice Doomed Necromancer: Return target creature card from your graveyard to the battlefield.