Necrotic Plague

Enchant creature
Enchanted creature has "At the beginning of your upkeep, sacrifice this creature."
When enchanted creature dies, its controller chooses target creature one of their opponents controls. Return Necrotic Plague from its owner's graveyard to the battlefield attached to that creature.

Fear of Lost Teeth

When Fear of Lost Teeth dies, it deals 1 damage to any target and you gain 1 life.

Smallpox

Each player loses 1 life, discards a card, sacrifices a creature of their choice, then sacrifices a land of their choice.

Vampiric Link

Enchant creature
Whenever enchanted creature deals damage, you gain that much life.

Curse of Disturbance

Enchant player
Whenever enchanted player is attacked, create a 2/2 black Zombie creature token. Each opponent attacking that player does the same.

Sloppity Bilepiper

Jolly Gutpipes — {2}, {T}, Sacrifice a creature: The next creature spell you cast this turn has cascade. (When you next cast a creature spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)

Swift End

Destroy target creature or planeswalker. You lose 2 life. (Then exile this card. You may cast the creature later from exile.)

Murderous Rider

Lifelink
When Murderous Rider dies, put it on the bottom of its owner's library.

Murderous Rider // Swift End

Rancid Rats

Skulk (This creature can't be blocked by creatures with greater power.)
Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)

Sangromancer

Flying
Whenever a creature an opponent controls dies, you may gain 3 life.
Whenever an opponent discards a card, you may gain 3 life.

Nurgle's Rot

Enchant creature an opponent controls
When enchanted creature dies, return Nurgle's Rot to its owner's hand and you create a 1/3 black Demon creature token named Plaguebearer of Nurgle.

Marshland Bloodcaster

Flying
{1}{B}, {T}: Rather than pay the mana cost of the next spell you cast this turn, you may pay life equal to that spell's mana value.

Swamp

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.

Ayara, First of Locthwain

Whenever Ayara, First of Locthwain or another black creature you control enters, each opponent loses 1 life and you gain 1 life.
{T}, Sacrifice another black creature: Draw a card.

Plague Wight

Whenever Plague Wight becomes blocked, each creature blocking it gets -1/-1 until end of turn.

Liliana's Reaver

Deathtouch
Whenever Liliana's Reaver deals combat damage to a player, that player discards a card and you create a tapped 2/2 black Zombie creature token.

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

Carrion Rats

Whenever Carrion Rats attacks or blocks, any player may exile a card from their graveyard. If a player does, Carrion Rats assigns no combat damage this turn.

Murder

Profane Transfusion

Two target players exchange life totals. You create an X/X colorless Horror artifact creature token, where X is the difference between those players' life totals.

Great Unclean One

Reverberating Summons — At the beginning of your end step, each opponent loses 2 life. Then for each opponent who has less life than you, create a 1/3 black Demon creature token named Plaguebearer of Nurgle.

Curse of Oblivion

Enchant player
At the beginning of enchanted player's upkeep, that player exiles two cards from their graveyard.

Plaguecrafter

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

Each player loses a third of their life, then discards a third of the cards in their hand, then sacrifices a third of the creatures they control of their choice, then sacrifices a third of the lands they control of their choice. Round up each time.

Defile

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

Gisa, Glorious Resurrector

If a creature an opponent controls would die, exile it instead.
At the beginning of your upkeep, put all creature cards exiled with Gisa, Glorious Resurrector onto the battlefield under your control. They gain decayed. (A creature with decayed can't block. When it attacks, sacrifice it at end of combat.)

Tavern Swindler

{T}, Pay 3 life: Flip a coin. If you win the flip, you gain 6 life.

Noxious Gearhulk

Menace
When Noxious Gearhulk enters, you may destroy another target creature. If a creature is destroyed this way, you gain life equal to its toughness.

Keen Duelist

At the beginning of your upkeep, you and target opponent each reveal the top card of your library. You each lose life equal to the mana value of the card revealed by the other player. You each put the card you revealed into your hand.

Torgaar, Famine Incarnate

As an additional cost to cast this spell, you may sacrifice any number of creatures. This spell costs {2} less to cast for each creature sacrificed this way.
When Torgaar, Famine Incarnate enters, up to one target player's life total becomes half their starting life total, rounded down.

Sporogenic Infection

Enchant creature
When Sporogenic Infection enters, target player sacrifices a creature of their choice other than enchanted creature.
When enchanted creature is dealt damage, destroy it.

Evolving Wilds

{T}, Sacrifice this land: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Veinwitch Coven

Menace
Whenever you gain life, you may pay {B}. If you do, return target creature card from your graveyard to your hand.

Blight Grenade

Destroy target creature.
All creatures get -3/-3 until end of turn.

Falkenrath Noble

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

Erebos's Intervention

Choose one —
• Target creature gets -X/-X until end of turn. You gain X life.
• Exile up to twice X target cards from graveyards.

Venomcrawler

Lifelink
Devourer of Souls — Whenever another creature dies, put a +1/+1 counter on Venomcrawler.

Dark Ritual

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.

Virulent Plague

Bile Blight

Target creature and all other creatures with the same name as that creature get -3/-3 until end of turn.

Overseer of the Damned

Flying
When Overseer of the Damned enters, you may destroy target creature.
Whenever a nontoken creature an opponent controls dies, create a tapped 2/2 black Zombie creature token.

Sol Ring

Bubbling Muck

Until end of turn, whenever a player taps a Swamp for mana, that player adds an additional {B}.

Astartes Warrior

Decree of Pain

Destroy all creatures. They can't be regenerated. Draw a card for each creature destroyed this way.
Cycling {3}{B}{B} ({3}{B}{B}, Discard this card: Draw a card.)
When you cycle Decree of Pain, all creatures get -2/-2 until end of turn.

Dross Harvester

Protection from white
At the beginning of your end step, you lose 4 life.
Whenever a creature dies, you gain 2 life.

Nurgle's Conscription

Put target creature card from an opponent's graveyard onto the battlefield tapped under your control, then exile that player's graveyard.

Curse of Shallow Graves

Enchant player
Whenever a player attacks enchanted player with one or more creatures, that attacking player may create a tapped 2/2 black Zombie creature token.

Vendetta

Destroy target nonblack creature. It can't be regenerated. You lose life equal to that creature's toughness.

Fanatic of the Harrowing

When Fanatic of the Harrowing enters, each player discards a card. If you discarded a card this way, draw a card.

Curse of Death's Hold

Enchant player
Creatures enchanted player controls get -1/-1.

Ravenous Rats

When Ravenous Rats enters, target opponent discards a card.

Mutilate

All creatures get -1/-1 until end of turn for each Swamp you control.

Mortarion, Daemon Primarch

Flying
Primarch of the Death Guard — At the beginning of your end step, you may pay {X}. If you do, create X 2/2 black Astartes Warrior creature tokens with menace. X can't be greater than the amount of life you lost this turn.

Blood Artist

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

Hero's Downfall

Poxwalkers

Deathtouch
Curse of the Walking Pox — Whenever you cast a spell from anywhere other than your hand, return Poxwalkers from your graveyard to the battlefield tapped.

Grievous Wound

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

Plague Mare

Plague Mare can't be blocked by white creatures.
When Plague Mare enters, creatures your opponents control get -1/-1 until end of turn.

Phyrexian Plaguelord

{T}, Sacrifice Phyrexian Plaguelord: Target creature gets -4/-4 until end of turn.
Sacrifice a creature: Target creature gets -1/-1 until end of turn.

Brood of Cockroaches

When Brood of Cockroaches is put into your graveyard from the battlefield, at the beginning of the next end step, you lose 1 life and return Brood of Cockroaches to your hand.

Endless Cockroaches

When Endless Cockroaches dies, return it to its owner's hand.

Typhoid Rats

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)

Duress

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

Liliana's Steward

{T}, Sacrifice Liliana's Steward: Target opponent discards a card. Activate only as a sorcery.

Plague Engineer

Deathtouch
As Plague Engineer enters, choose a creature type.
Creatures of the chosen type your opponents control get -1/-1.

Come Back Wrong

Destroy target creature. If a creature card is put into a graveyard this way, return it to the battlefield under your control. Sacrifice it at the beginning of your next end step.

Liliana's Elite

Liliana's Elite gets +1/+1 for each creature card in your graveyard.

Withering Torment

Destroy target creature or enchantment. You lose 2 life.

Engineered Plague

As Engineered Plague enters, choose a creature type.
All creatures of the chosen type get -1/-1.

Feral Ghoul

Menace
Whenever another creature you control dies, put a +1/+1 counter on Feral Ghoul.
When Feral Ghoul dies, each opponent gets a number of rad counters equal to its power.

Ambition's Cost

You draw three cards and you lose 3 life.

Curse of Wizardry

As Curse of Wizardry enters, choose a color.
Whenever a player casts a spell of the chosen color, that player loses 1 life.

Pact of the Serpent

Choose a creature type. Target player draws X cards and loses X life, where X is the number of creatures they control of the chosen type.

Plague Drone

Flying
Rot Fly — If an opponent would gain life, that player loses that much life instead.