Descent into Avernus

At the beginning of your upkeep, put two descent counters on Descent into Avernus. Then each player creates X Treasure tokens and Descent into Avernus deals X damage to each player, where X is the number of descent counters on Descent into Avernus.

Smoldering Marsh

({T}: Add {B} or {R}.)
Smoldering Marsh enters tapped unless you control two or more basic lands.

Demand Answers

As an additional cost to cast this spell, sacrifice an artifact or discard a card.
Draw two cards.

Rakdos Signet

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.

Phyrexian Arena

At the beginning of your upkeep, you draw a card and you lose 1 life.

Wheel of Misfortune

Each player secretly chooses a number 0 or greater, then all players reveal those numbers simultaneously and determine the highest and lowest numbers revealed this way. Wheel of Misfortune deals damage equal to the highest number to each player who chose that number. Each player who didn't choose the lowest number discards their hand, then draws seven cards.

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.

Jet Medallion

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

Fire Diamond

Fire Diamond enters tapped.
{T}: Add {R}.

Swamp

Havoc Festival

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

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.)

Doom Blade

Creeping Bloodsucker

At the beginning of your upkeep, Creeping Bloodsucker deals 1 damage to each opponent. You gain life equal to the damage dealt this way.

Scytheclaw Raptor

Whenever a player casts a spell, if it's not their turn, Scytheclaw Raptor deals 4 damage to them.

Mountain

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.

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Dragonskull Summit

Dragonskull Summit enters tapped unless you control a Swamp or a Mountain.
{T}: Add {B} or {R}.

Commander's Sphere

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

Loyal Subordinate

Menace (This creature can't be blocked except by two or more creatures.)
Lieutenant — At the beginning of combat on your turn, if you control your commander, each opponent loses 3 life.

Spellshock

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

Dark Ritual

Talisman of Indulgence

{T}: Add {C}.
{T}: Add {B} or {R}. Talisman of Indulgence deals 1 damage to you.

Temple of Malice

Temple of Malice enters tapped.
When Temple of Malice enters, scry 1.
{T}: Add {B} or {R}.

Risk Factor

Target opponent may have Risk Factor deal 4 damage to them. If that player doesn't, you draw three cards.
Jump-start (You may cast this card from your graveyard by discarding a card in addition to paying its other costs. Then exile this card.)

Price of Progress

Price of Progress deals damage to each player equal to twice the number of nonbasic lands that player controls.

Ankh of Mishra

Whenever a land enters, Ankh of Mishra deals 2 damage to that land's controller.

Terminate

Destroy target creature. It can't be regenerated.

Syphon Mind

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

Swiftfoot Boots

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

Foreboding Ruins

As Foreboding Ruins enters, you may reveal a Swamp or Mountain card from your hand. If you don't, Foreboding Ruins enters tapped.
{T}: Add {B} or {R}.

Crawlspace

No more than two creatures can attack you each combat.

Thrill of Possibility

As an additional cost to cast this spell, discard a card.
Draw two cards.

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.

Command Tower

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

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.)

Solphim, Mayhem Dominus

If a source you control would deal noncombat damage to an opponent or a permanent an opponent controls, it deals double that damage to that player or permanent instead.
{1}{R/P}{R/P}, Discard two cards: Put an indestructible counter on Solphim, Mayhem Dominus. ({R/P} can be paid with either {R} or 2 life.)

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.

God-Pharaoh's Statue

Spells your opponents cast cost {2} more to cast.
At the beginning of your end step, each opponent loses 1 life.

Magebane Lizard

Whenever a player casts a noncreature spell, Magebane Lizard deals damage to that player equal to the number of noncreature spells they've cast this turn.

Painful Quandary

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

Rakdos Charm

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

Kaervek the Merciless

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

Fate Unraveler

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

Brash Taunter

Indestructible
Whenever Brash Taunter is dealt damage, it deals that much damage to target opponent.
{2}{R}, {T}: Brash Taunter fights another target creature.

Mind Stone

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

Rakdos Locket

{T}: Add {B} or {R}.
{B/R}{B/R}{B/R}{B/R}, {T}, Sacrifice Rakdos Locket: Draw two cards.

Blasphemous Act

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

Ruby Medallion

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

Sol Ring

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.

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.

Underworld Dreams

Whenever an opponent draws a card, Underworld Dreams deals 1 damage to that player.

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.")

Deadly Tempest

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

Path of Ancestry

Path of Ancestry enters tapped.
{T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Kardur, Doomscourge

When Kardur, Doomscourge enters, until your next turn, creatures your opponents control attack each combat if able and attack a player other than you if able.
Whenever an attacking creature dies, each opponent loses 1 life and you gain 1 life.

Abrade

Choose one —
• Abrade deals 3 damage to target creature.
• Destroy target artifact.

Stormfist Crusader

Menace
At the beginning of your upkeep, each player draws a card and loses 1 life.

Charcoal Diamond

Charcoal Diamond enters tapped.
{T}: Add {B}.

Heartless Hidetsugu

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

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.)

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.

Zo-Zu the Punisher

Whenever a land enters, Zo-Zu the Punisher deals 2 damage to that land's controller.

Rakdos, Patron of Chaos

Flying, trample
At the beginning of your end step, target opponent may sacrifice two nonland, nontoken permanents of their choice. If they don't, you draw two cards.

No Mercy

Whenever a creature deals damage to you, destroy it.

Unlicensed Disintegration

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

Manabarbs

Whenever a player taps a land for mana, Manabarbs deals 1 damage to that player.

Bedevil

Destroy target artifact, creature, or planeswalker.

Arcane Signet

Polluted Bonds

Whenever a land an opponent controls enters, that player loses 2 life and you gain 2 life.