Liliana of the Veil

+1: Each player discards a card.
−2: Target player sacrifices a creature.
−6: Separate all permanents target player controls into two piles. That player sacrifices all permanents in the pile of their choice.

Urborg, Tomb of Yawgmoth

Each land is a Swamp in addition to its other land types.

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.

Vampiric Tutor

Search your library for a card, then shuffle and put that card on top. You lose 2 life.

Hero's Downfall

Ancient Tomb

{T}: Add {C}{C}. Ancient Tomb deals 2 damage to you.

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, then sacrifices a third of the lands they control. Round up each time.

Rotting Rats

When Rotting Rats enters the battlefield, each player discards a card.
Unearth {1}{B} ({1}{B}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)

Skull Raid

Target opponent discards two cards. If fewer than two cards were discarded this way, you draw cards equal to the difference.
Foretell {1}{B} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Torment of Hailfire

Repeat the following process X times. Each opponent loses 3 life unless that player sacrifices a nonland permanent or discards a card.

Jet Medallion

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

Lightning Greaves

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

Bitterblossom

At the beginning of your upkeep, you lose 1 life and create a 1/1 black Faerie Rogue creature token with flying.

Hagra Broodpit

Hagra Broodpit enters the battlefield tapped.
{T}: Add {B}.

Hagra Mauling

This spell costs {1} less to cast if an opponent controls no basic lands.
Destroy target creature.

Hagra Mauling // Hagra Broodpit

Soul Shatter

Each opponent sacrifices a creature or planeswalker with the highest mana value among creatures and planeswalkers they control.

Malakir Mire

Malakir Mire enters the battlefield tapped.
{T}: Add {B}.

Malakir Rebirth

Choose target creature. You lose 2 life. Until end of turn, that creature gains "When this creature dies, return it to the battlefield tapped under its owner's control."

Malakir Rebirth // Malakir Mire

War Room

{T}: Add {C}.
{3}, {T}, Pay life equal to the number of colors in your commanders' color identity: Draw a card.

Demonic Tutor

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

Arterial Flow

Each opponent discards two cards. If you control a Vampire, each opponent loses 2 life and you gain 2 life.

Smokestack

At the beginning of your upkeep, you may put a soot counter on Smokestack.
At the beginning of each player's upkeep, that player sacrifices a permanent for each soot counter on Smokestack.

Reanimate

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

Dark Deal

Each player discards all the cards in their hand, then draws that many cards minus one.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control.)
Equip {1}

Burglar Rat

When Burglar Rat enters the battlefield, each opponent discards a card.

Merciless Executioner

When Merciless Executioner enters the battlefield, each player sacrifices a creature.

Myriad Landscape

Myriad Landscape enters the battlefield tapped.
{T}: Add {C}.
{2}, {T}, Sacrifice Myriad Landscape: Search your library for up to two basic land cards that share a land type, put them onto the battlefield tapped, then shuffle.

Cabal Coffers

{2}, {T}: Add {B} for each Swamp you control.

Death Cloud

Each player loses X life, discards X cards, sacrifices X creatures, then sacrifices X lands.

Ambition's Cost

You draw three cards and you lose 3 life.

Hymn to Tourach

Target player discards two cards at random.

Sol Ring

Demon's Disciple

When Demon's Disciple enters the battlefield, each player sacrifices a creature or planeswalker.

Elderfang Disciple

When Elderfang Disciple enters the battlefield, each opponent discards a card.

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."

Smallpox

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

Jeweled Lotus

{T}, Sacrifice Jeweled Lotus: Add three mana of any one color. Spend this mana only to cast your commander.

Geth's Grimoire

Whenever an opponent discards a card, you may draw a card.

Fraying Omnipotence

Each player loses half their life, then discards half the cards in their hand, then sacrifices half the creatures they control. Round up each time.

Grim Monolith

Grim Monolith doesn't untap during your untap step.
{T}: Add {C}{C}{C}.
{4}: Untap Grim Monolith.

Arcane Signet

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

Feed the Swarm

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

Mire in Misery

Each opponent sacrifices a creature or enchantment.

Chains of Mephistopheles

If a player would draw a card except the first one they draw in each of their draw steps, that player discards a card instead. If the player discards a card this way, they draw a card. If the player doesn't discard a card this way, they mill a card.

Tasigur's Cruelty

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

Read the Bones

Scry 2, then draw two cards. You lose 2 life.

Skeletal Scrying

As an additional cost to cast this spell, exile X cards from your graveyard.
You draw X cards and you lose X life.

Liliana's Specter

Flying
When Liliana's Specter enters the battlefield, each opponent discards a card.

Underworld Connections

Enchant land
Enchanted land has "{T}, Pay 1 life: Draw a card."

Pharika's Libation

Choose one —
• Target opponent sacrifices a creature.
• Target opponent sacrifices an enchantment.

Necrotic Hex

Each player sacrifices six creatures. You create six tapped 2/2 black Zombie creature tokens.

All Is Dust

Each player sacrifices all permanents they control that are one or more colors.

Fleshbag Marauder

When Fleshbag Marauder enters the battlefield, each player sacrifices a creature.

Cabal Stronghold

{T}: Add {C}.
{3}, {T}: Add {B} for each basic Swamp you control.

Tergrid's Lantern

{T}: Target player loses 3 life unless they sacrifice a nonland permanent 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

Waste Not

Whenever an opponent discards a creature card, create a 2/2 black Zombie creature token.
Whenever an opponent discards a land card, add {B}{B}.
Whenever an opponent discards a noncreature, nonland card, draw a card.

Innocent Blood

Grim Tutor

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

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice Mind Stone: Draw a card.

Geier Reach Sanitarium

{T}: Add {C}.
{2}, {T}: Each player draws a card, then discards a card.

Bubbling Muck

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

Liliana's Triumph

Each opponent sacrifices a creature. If you control a Liliana planeswalker, each opponent also discards a card.

Pelakka Caverns

Pelakka Caverns enters the battlefield tapped.
{T}: Add {B}.

Pelakka Predation

Target opponent reveals their hand. You choose a card from it with mana value 3 or greater. That player discards that card.

Pelakka Predation // Pelakka Caverns

Castle Locthwain

Castle Locthwain enters the battlefield tapped unless you control a Swamp.
{T}: Add {B}.
{1}{B}{B}, {T}: Draw a card, then you lose life equal to the number of cards in your hand.

Contamination

At the beginning of your upkeep, sacrifice Contamination unless you sacrifice a creature.
If a land is tapped for mana, it produces {B} instead of any other type and amount.

Vicious Rumors

Vicious Rumors deals 1 damage to each opponent. Each opponent discards a card, then mills a card. You gain 1 life.

Damnation

Destroy all creatures. They can't be regenerated.

Withering Boon

As an additional cost to cast this spell, pay 3 life.
Counter target creature spell.

Dreadhorde Invasion

At the beginning of your upkeep, you lose 1 life and amass Zombies 1. (Put a +1/+1 counter on an Army you control. It's also a Zombie. If you don't control an Army, create a 0/0 black Zombie Army creature token first.)
Whenever a Zombie token you control with power 6 or greater attacks, it gains lifelink until end of turn.

Grave Pact

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

Dark Ritual

Plaguecrafter

When Plaguecrafter enters the battlefield, each player sacrifices a creature or planeswalker. Each player who can't discards a card.

Vona's Hunger

Ascend (If you control ten or more permanents, you get the city's blessing for the rest of the game.)
Each opponent sacrifices a creature. If you have the city's blessing, instead each opponent sacrifices half the creatures they control, rounded up.

Syphon Mind

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

The Eldest Reborn

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Each opponent sacrifices a creature or planeswalker.
II — Each opponent discards a card.
III — Put target creature or planeswalker card from a graveyard onto the battlefield under your control.

Ophiomancer

At the beginning of each upkeep, if you control no Snakes, create a 1/1 black Snake creature token with deathtouch.

Swamp

Dictate of Erebos

Flash
Whenever a creature you control dies, each opponent sacrifices a creature.