Spawnsire of Ulamog

Annihilator 1 (Whenever this creature attacks, defending player sacrifices a permanent of their choice.)
{4}: Create two 0/1 colorless Eldrazi Spawn creature tokens. They have "Sacrifice this token: Add {C}."
{20}: Cast any number of Eldrazi spells from among cards you own outside the game without paying their mana costs.

Gruesome Discovery

Target player discards two cards.
Morbid — If a creature died this turn, instead that player reveals their hand, you choose two cards from it, then that player discards those cards.

Bojuka Bog

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

Rictus Robber

When this creature enters, if a creature died this turn, create a 2/2 blue and black Zombie Rogue creature token.
Plot {2}{B} (You may pay {2}{B} and exile this card from your hand. Cast it as a sorcery on a later turn without paying its mana cost. Plot only as a sorcery.)

Wakedancer

Morbid — When this creature enters, if a creature died this turn, create a 2/2 black Zombie creature token.

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.

Séance Board

Morbid — At the beginning of each end step, if a creature died this turn, put a soul counter on this artifact.
{T}: Add X mana of any one color, where X is the number of soul counters on this artifact. Spend this mana only to cast instant, sorcery, Demon, and Spirit spells.

Bone Picker

This spell costs {3} less to cast if a creature died this turn.
Flying, deathtouch

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Elegy Acolyte

Lifelink
Whenever one or more creatures you control deal combat damage to a player, you draw a card and lose 1 life.
Void — At the beginning of your end step, if a nonland permanent left the battlefield this turn or a spell was warped this turn, create a 2/2 colorless Robot artifact creature token.

Darksteel Plate

Indestructible
Equipped creature has indestructible.
Equip {2}

Death-Priest of Myrkul

Skeletons, Vampires, and Zombies you control get +1/+1.
At the beginning of your end step, if a creature died this turn, you may pay {1}. If you do, create a 1/1 black Skeleton creature token.

Archfiend of Despair

Flying
Your opponents can't gain life.
At the beginning of each end step, each opponent loses life equal to the life that player lost this turn. (Damage causes loss of life.)

Timeline Culler

Haste
You may cast this card from your graveyard using its warp ability.
Warp—{B}, Pay 2 life. (You may cast this card from your hand or graveyard for its warp cost. If you do, exile this creature at the beginning of the next end step, then you may cast it from exile on a later turn.)

Grim Wanderer

Flash
Tragic Backstory — Cast this spell only if a creature died this turn.

Bygone Colossus

Warp {3} (You may cast this card from your hand for its warp cost. Exile this creature at the beginning of the next end step, then you may cast it from exile on a later turn.)

Insatiable Skittermaw

Menace (This creature can't be blocked except by two or more creatures.)
Void — At the beginning of your end step, if a nonland permanent left the battlefield this turn or a spell was warped this turn, put a +1/+1 counter on this creature.

Black Market

Whenever a creature dies, put a charge counter on this enchantment.
At the beginning of your first main phase, add {B} for each charge counter on this enchantment.

Blacksnag Buzzard

Flying
This creature enters with a +1/+1 counter on it if a creature died this turn.
Plot {1}{B} (You may pay {1}{B} and exile this card from your hand. Cast it as a sorcery on a later turn without paying its mana cost. Plot only as a sorcery.)

Dread Summons

Each player mills X cards. For each creature card put into a graveyard this way, you create a tapped 2/2 black Zombie creature token. (To mill a card, a player puts the top card of their library into their graveyard.)

That Which Was Taken

{4}, {T}: Put a divinity counter on target permanent other than That Which Was Taken.
Each permanent with a divinity counter on it has indestructible.

Agent of the Iron Throne

Commander creatures you own have "Whenever an artifact or creature you control is put into a graveyard from the battlefield, each opponent loses 1 life."

Eumidian Hatchery

{T}, Pay 1 life: Add {B}. Put a hatchling counter on this land.
When this land is put into a graveyard from the battlefield, for each hatchling counter on it, create a 1/1 black Insect creature token with flying.

Sephiroth, One-Winged Angel

Flying
Super Nova — As this creature transforms into Sephiroth, One-Winged Angel, you get an emblem with "Whenever a creature dies, target opponent loses 1 life and you gain 1 life."
Whenever Sephiroth attacks, you may sacrifice any number of other creatures. If you do, draw that many cards.

Sephiroth, Fabled SOLDIER

Whenever Sephiroth enters or attacks, you may sacrifice another creature. If you do, draw a card.
Whenever another creature dies, target opponent loses 1 life and you gain 1 life. If this is the fourth time this ability has resolved this turn, transform Sephiroth.

Sephiroth, Fabled SOLDIER // Sephiroth, One-Winged Angel

Tallyman of Nurgle

Lifelink
The Seven-fold Chant — At the beginning of your end step, if a creature died this turn, you draw a card and you lose 1 life. If seven or more creatures died this turn, instead you draw seven cards and you lose 7 life.

Voidforged Titan

Void — At the beginning of your end step, if a nonland permanent left the battlefield this turn or a spell was warped this turn, you draw a card and lose 1 life.

Champion's Helm

Equipped creature gets +2/+2.
As long as equipped creature is legendary, it has hexproof. (It can't be the target of spells or abilities your opponents control.)
Equip {1}

Malicious Affliction

Morbid — When you cast this spell, if a creature died this turn, you may copy Malicious Affliction and may choose a new target for the copy.
Destroy target nonblack creature.

Chorale of the Void

Enchant creature you control
Whenever enchanted creature attacks, put target creature card from defending player's graveyard onto the battlefield under your control tapped and attacking.
Void — At the beginning of your end step, sacrifice this Aura unless a nonland permanent left the battlefield this turn or a spell was warped this turn.

Dunes of the Dead

{T}: Add {C}.
When this land is put into a graveyard from the battlefield, create a 2/2 black Zombie creature token.

Sting, the Glinting Dagger

Equipped creature gets +1/+1 and has haste.
At the beginning of each combat, untap equipped creature.
Equipped creature has first strike as long as it's blocking or blocked by a Goblin or Orc.
Equip {2}

Gravelighter

Flying
When this creature enters, draw a card if a creature died this turn. Otherwise, each player sacrifices a creature of their choice.

Obsidian Battle-Axe

Equipped creature gets +2/+1 and has haste.
Whenever a Warrior creature enters, you may attach this Equipment to it.
Equip {3}

Liliana, Defiant Necromancer

+2: Each player discards a card.
−X: Return target nonlegendary creature card with mana value X from your graveyard to the battlefield.
−8: You get an emblem with "Whenever a creature dies, return it to the battlefield under your control at the beginning of the next end step."

Liliana, Heretical Healer

Lifelink
Whenever another nontoken creature you control dies, exile Liliana, Heretical Healer, then return her to the battlefield transformed under her owner's control. If you do, create a 2/2 black Zombie creature token.

Liliana, Heretical Healer // Liliana, Defiant Necromancer

Hammer of Nazahn

Whenever Hammer of Nazahn or another Equipment you control enters, you may attach that Equipment to target creature you control.
Equipped creature gets +2/+0 and has indestructible.
Equip {4}

Necromantic Selection

Destroy all creatures, then return a creature card put into a graveyard this way to the battlefield under your control. It's a black Zombie in addition to its other colors and types. Exile Necromantic Selection.

Swamp

Alpharael, Stonechosen

Ward—Discard a card at random.
Void — Whenever Alpharael attacks, if a nonland permanent left the battlefield this turn or a spell was warped this turn, defending player loses half their life, rounded up.

Blight Herder

When you cast this spell, you may put two cards your opponents own from exile into their owners' graveyards. If you do, create three 1/1 colorless Eldrazi Scion creature tokens. They have "Sacrifice this token: Add {C}."

Strider Harness

Equipped creature gets +1/+1 and has haste.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Vrock

Flying
Toxic Spores — At the beginning of your end step, if a permanent you controlled left the battlefield this turn, each opponent loses 3 life.

Quest for the Gravelord

Whenever a creature dies, you may put a quest counter on this enchantment.
Remove three quest counters from this enchantment and sacrifice it: Create a 5/5 black Zombie Giant creature token.

Corpsehatch

Destroy target nonblack creature. Create two 0/1 colorless Eldrazi Spawn creature tokens. They have "Sacrifice this token: Add {C}."

Bloodletter of Aclazotz

Flying
If an opponent would lose life during your turn, they lose twice that much life instead. (Damage causes loss of life.)

Sol Ring

Spawning Bed

{T}: Add {C}.
{6}, {T}, Sacrifice this land: Create three 1/1 colorless Eldrazi Scion creature tokens. They have "Sacrifice this token: Add {C}."

Yoke of the Damned

Enchant creature
When a creature dies, destroy enchanted creature.

Temporal Intervention

Void — This spell costs {2} less to cast if a nonland permanent left the battlefield this turn or a spell was warped this turn.
Target opponent reveals their hand. You choose a nonland card from it. That player discards that card.

Eumidian Wastewaker

Whenever this creature attacks, you and defending player each discard a card or sacrifice a permanent. You draw a card for each land card put into a graveyard this way.
Encore {6}{B}{B} ({6}{B}{B}, Exile this card from your graveyard: For each opponent, create a token copy that attacks that opponent this turn if able. They gain haste. Sacrifice them at the beginning of the next end step. Activate only as a sorcery.)

Zero Point Ballad

Destroy all creatures with toughness X or less. You lose X life. If X is 6 or more, return a creature card put into a graveyard this way to the battlefield under your control.

Essence Feed

Target player loses 3 life. You gain 3 life and create three 0/1 colorless Eldrazi Spawn creature tokens. They have "Sacrifice this token: Add {C}."

Lavaspur Boots

Equipped creature gets +1/+0 and has haste and ward {1}. (Whenever it becomes the target of a spell or ability an opponent controls, counter it unless that player pays {1}.)
Equip {1}

Tragic Banshee

Morbid — When this creature enters, target creature an opponent controls gets -1/-1 until end of turn. If a creature died this turn, that creature gets -13/-13 until end of turn instead.

Jet Medallion

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

Grievous Wound

Enchant player
Enchanted player can't gain life.
Whenever enchanted player is dealt damage, they lose half their life, rounded up.

Decode Transmissions

You draw two cards and lose 2 life.
Void — If a nonland permanent left the battlefield this turn or a spell was warped this turn, instead you draw two cards and each opponent loses 2 life.

Dread Drone

When this creature enters, create two 0/1 colorless Eldrazi Spawn creature tokens. They have "Sacrifice this token: Add {C}."

Vein Ripper

Flying
Ward—Sacrifice a creature.
Whenever a creature dies, target opponent loses 2 life and you gain 2 life.

Ring of Valkas

Equipped creature has haste. (It can attack and {T} no matter when it came under your control.)
At the beginning of your upkeep, put a +1/+1 counter on equipped creature if it's red.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Skittering Invasion

Create five 0/1 colorless Eldrazi Spawn creature tokens. They have "Sacrifice this token: Add {C}."

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.)

Liliana's Devotee

Zombies you control get +1/+0.
At the beginning of your end step, if a creature died this turn, you may pay {1}{B}. If you do, create a 2/2 black Zombie creature token.

Anticausal Vestige

When this creature leaves the battlefield, draw a card, then you may put a permanent card with mana value less than or equal to the number of lands you control from your hand onto the battlefield tapped.
Warp {4} (You may cast this card from your hand for its warp cost. Exile this creature at the beginning of the next end step, then you may cast it from exile on a later turn.)

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.)

Unstoppable Slasher

Deathtouch
Whenever this creature deals combat damage to a player, they lose half their life, rounded up.
When this creature dies, if it had no counters on it, return it to the battlefield tapped under its owner's control with two stun counters on it.

Corrupt

Corrupt deals damage to any target equal to the number of Swamps you control. You gain life equal to the damage dealt this way.

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.

Necropouncer

Living weapon (When this Equipment enters, create a 0/0 black Phyrexian Germ creature token, then attach this to it.)
Equipped creature gets +3/+1 and has haste.
Equip {2}

Wound Reflection

At the beginning of each end step, each opponent loses life equal to the life they lost this turn. (Damage causes loss of life.)

Mithril Coat

Flash
Indestructible
When Mithril Coat enters, attach it to target legendary creature you control.
Equipped creature has indestructible.
Equip {3}

Abhorrent Overlord

Flying
When this creature 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.

Tragic Trajectory

Target creature gets -2/-2 until end of turn.
Void — That creature gets -10/-10 until end of turn instead if a nonland permanent left the battlefield this turn or a spell was warped this turn.

Warlock Class

(Gain the next level as a sorcery to add its ability.)
At the beginning of your end step, if a creature died this turn, each opponent loses 1 life.
{1}{B}: Level 2
When this Class becomes level 2, look at the top three cards of your library. Put one of them into your hand and the rest into your graveyard.
{6}{B}: Level 3
At the beginning of your end step, each opponent loses life equal to the life they lost this turn. (Damage causes loss of life.)

Bilbo's Ring

During your turn, equipped creature has hexproof and can't be blocked.
Whenever equipped creature attacks alone, you draw a card and you lose 1 life.
Equip Halfling {1} ({1}: Attach to target Halfling you control. Equip only as a sorcery.)
Equip {4} ({4}: Attach to target creature you control. Equip only as a sorcery.)