Torment of Hailfire

Repeat the following process X times. Each opponent loses 3 life unless that player sacrifices a nonland permanent of their choice or discards 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 of their choice. Round up each time.

Murder

Fanatic of Mogis

When Fanatic of Mogis enters, it deals damage to each opponent equal to your devotion to red. (Each {R} in the mana costs of permanents you control counts toward your devotion to red.)

Bloodfell Caves

This land enters tapped.
When this land enters, you gain 1 life.
{T}: Add {B} or {R}.

Plaguecrafter

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

Rakdos, the Showstopper

Flying, trample
When Rakdos, the Showstopper enters, flip a coin for each creature that isn't a Demon, Devil, or Imp. Destroy each creature whose coin comes up tails.

Temple of Malice

This land enters tapped.
When this land enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)
{T}: Add {B} or {R}.

Dire Fleet Ravager

Menace, deathtouch
When Dire Fleet Ravager enters, each player loses a third of their life, rounded up.

Chaos Warp

The owner of target permanent shuffles it into their library, then reveals the top card of their library. If it's a permanent card, they put it onto the battlefield.

Furnace of Rath

If a source would deal damage to a permanent or player, it deals double that damage to that permanent or player instead.

Vandalblast

Destroy target artifact you don't control.
Overload {4}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Rakdos Carnarium

Rakdos Carnarium enters tapped.
When Rakdos Carnarium enters, return a land you control to its owner's hand.
{T}: Add {B}{R}.

Rakdos Signet

Jaya, Venerated Firemage

If another red source you control would deal damage to a permanent or player, it deals that much damage plus 1 to that permanent or player instead.
−2: Jaya, Venerated Firemage deals 2 damage to any target.

Captive Audience

Captive Audience enters under the control of an opponent of your choice.
At the beginning of your upkeep, choose one that hasn't been chosen —
• Your life total becomes 4.
• Discard your hand.
• Each opponent creates five 2/2 black Zombie creature tokens.

Leechridden Swamp

({T}: Add {B}.)
Leechridden Swamp enters tapped.
{B}, {T}: Each opponent loses 1 life. Activate only if you control two or more black permanents.

Swamp

Sulfuric Vortex

At the beginning of each player's upkeep, Sulfuric Vortex deals 2 damage to that player.
If a player would gain life, that player gains no life instead.

Spellshock

Whenever a player casts a spell, Spellshock deals 2 damage to that player.

Torbran, Thane of Red Fell

If a red source you control would deal damage to an opponent or a permanent an opponent controls, it deals that much damage plus 2 instead.

Chain Reaction

Chain Reaction deals X damage to each creature, where X is the number of creatures on the battlefield.

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.

Fate Unraveler

Whenever an opponent draws a card, Fate Unraveler deals 1 damage to that player.

Rakdos, Lord of Riots

You can't cast Rakdos, Lord of Riots unless an opponent lost life this turn.
Flying, trample
Creature spells you cast cost {1} less to cast for each 1 life your opponents have lost this turn.

Ob Nixilis, Unshackled

Flying, trample
Whenever an opponent searches their library, that player sacrifices a creature of their choice and loses 10 life.
Whenever another creature dies, put a +1/+1 counter on Ob Nixilis, Unshackled.

Mogis, God of Slaughter

Indestructible
As long as your devotion to black and red is less than seven, Mogis isn't a creature.
At the beginning of each opponent's upkeep, Mogis deals 2 damage to that player unless they sacrifice a creature of their choice.

Bedevil

Destroy target artifact, creature, or planeswalker.

Underworld Connections

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

Last One Standing

Choose a creature at random, then destroy the rest.

Heartless Hidetsugu

{T}: Heartless Hidetsugu deals damage to each player equal to half that player's life total, rounded down.

Unlicensed Disintegration

Destroy target creature. If you control an artifact, Unlicensed Disintegration deals 3 damage to that creature's controller.

Syphon Mind

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

Bloodchief Ascension

At the beginning of each end step, if an opponent lost 2 or more life this turn, you may put a quest counter on Bloodchief Ascension. (Damage causes loss of life.)
Whenever a card is put into an opponent's graveyard from anywhere, if Bloodchief Ascension has three or more quest counters on it, you may have that player lose 2 life. If you do, you gain 2 life.

Havoc Festival

Players can't gain life.
At the beginning of each player's upkeep, that player loses half their life, rounded up.

Dictate of the Twin Gods

Flash
If a source would deal damage to a permanent or player, it deals double that damage to that permanent or player instead.

Sudden Spoiling

Split second (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)
Until end of turn, creatures target player controls lose all abilities and have base power and toughness 0/2.

Rampaging Ferocidon

Menace
Players can't gain life.
Whenever another creature enters, Rampaging Ferocidon deals 1 damage to that creature's controller.

Bolas's Citadel

You may look at the top card of your library any time.
You may play lands and cast spells from the top of your library. If you cast a spell this way, pay life equal to its mana value rather than pay its mana cost.
{T}, Sacrifice ten nonland permanents: Each opponent loses 10 life.

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.)

Tibalt, Rakish Instigator

Your opponents can't gain life.
−2: Create a 1/1 red Devil creature token with "When this creature dies, it deals 1 damage to any target."

Mountain

Commander's Sphere

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

Command Tower

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

Exsanguinate

Each opponent loses X life. You gain life equal to the life lost this way.

Archfiend of Depravity

Flying
At the beginning of each opponent's end step, that player chooses up to two creatures they control, then sacrifices the rest.

Angrath's Marauders

If a source you control would deal damage to a permanent or player, it deals double that damage to that permanent or player instead.

Ribbons

Aftermath (Cast this spell only from your graveyard. Then exile it.)
Each opponent loses X life.

Cut // Ribbons

Ob Nixilis, the Hate-Twisted

Whenever an opponent draws a card, Ob Nixilis, the Hate-Twisted deals 1 damage to that player.
−2: Destroy target creature. Its controller draws two cards.

Starstorm

Starstorm deals X damage to each creature.
Cycling {3} ({3}, Discard this card: Draw a card.)

Neheb, the Eternal

Afflict 3 (Whenever this creature becomes blocked, defending player loses 3 life.)
At the beginning of each of your postcombat main phases, add {R} for each 1 life your opponents have lost this turn.

Read the Bones

Scry 2, then draw two cards. You lose 2 life. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Dreadbore

Palace Siege

As Palace Siege enters, choose Khans or Dragons.
• Khans — At the beginning of your upkeep, return target creature card from your graveyard to your hand.
• Dragons — At the beginning of your upkeep, each opponent loses 2 life and you gain 2 life.

Mindcrank

Whenever an opponent loses life, that player mills that many cards. (Damage causes loss of life.)

Kaervek the Merciless

Whenever an opponent casts a spell, Kaervek the Merciless deals damage equal to that spell's mana value to any target.

Spiteful Visions

At the beginning of each player's draw step, that player draws an additional card.
Whenever a player draws a card, Spiteful Visions deals 1 damage to that player.

Angrath, the Flame-Chained

+1: Each opponent discards a card and loses 2 life.
−3: Gain control of target creature until end of turn. Untap it. It gains haste until end of turn. Sacrifice it at the beginning of the next end step if it has mana value 3 or less.
−8: Each opponent loses life equal to the number of cards in their graveyard.

Davriel, Rogue Shadowmage

At the beginning of each opponent's upkeep, if that player has one or fewer cards in hand, Davriel, Rogue Shadowmage deals 2 damage to them.
−1: Target player discards a card.

Indulgent Tormentor

Flying
At the beginning of your upkeep, draw a card unless target opponent sacrifices a creature of their choice or pays 3 life.

Rakdos Charm

Choose one —
• Exile target player's graveyard.
• Destroy target artifact.
• Each creature deals 1 damage to its controller.

Blasphemous Act

This spell costs {1} less to cast for each creature on the battlefield.
Blasphemous Act deals 13 damage to each creature.

Painful Quandary

Whenever an opponent casts a spell, that player loses 5 life unless they discard a card.

Akoum Refuge

Akoum Refuge enters tapped.
When Akoum Refuge enters, you gain 1 life.
{T}: Add {B} or {R}.

Skull Rend

Skull Rend deals 2 damage to each opponent. Those players each discard two cards at random.

Sol Ring

Harsh Mentor

Whenever an opponent activates an ability of an artifact, creature, or land on the battlefield, if it isn't a mana ability, Harsh Mentor deals 2 damage to that player.

Chandra, Fire Artisan

Whenever one or more loyalty counters are removed from Chandra, Fire Artisan, she deals that much damage to target opponent or planeswalker.
+1: Exile the top card of your library. You may play it this turn.
−7: Exile the top seven cards of your library. You may play them this turn.

Deadly Tempest

Destroy all creatures. Each player loses life equal to the number of creatures they controlled that were destroyed this way.

Gray Merchant of Asphodel

When Gray Merchant of Asphodel 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.)