Theater of Horrors

At the beginning of your upkeep, exile the top card of your library.
During your turn, if an opponent lost life this turn, you may play lands and cast spells from among cards exiled with this enchantment.
{3}{R}: This enchantment deals 1 damage to target opponent or planeswalker.

Undercity's Embrace

Target opponent sacrifices a creature of their choice. If you control a creature with power 4 or greater, you gain 4 life.

Arcane Signet

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

Rakdos Drake

Flying
Unleash (You may have this creature enter with a +1/+1 counter on it. It can't block as long as it has a +1/+1 counter on it.)

Command Tower

Hellhole Flailer

Unleash (You may have this creature enter with a +1/+1 counter on it. It can't block as long as it has a +1/+1 counter on it.)
{2}{B}{R}, Sacrifice this creature: It deals damage equal to its power to target player or planeswalker.

Ogre Jailbreaker

Defender
This creature can attack as though it didn't have defender as long as you control a Gate.

Rakdos, Lord of Riots

You can't cast Rakdos 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.

Deviant Glee

Enchant creature
Enchanted creature gets +2/+1 and has "{R}: This creature gains trample until end of turn."

Rakdos Firewheeler

When this creature enters, it deals 2 damage to target opponent and 2 damage to up to one target creature or planeswalker.

Mark for Death

Target creature an opponent controls blocks this turn if able. Untap that creature. Other creatures that player controls can't block this turn.

Carnival Hellsteed

First strike, haste
Unleash (You may have this creature enter with a +1/+1 counter on it. It can't block as long as it has a +1/+1 counter on it.)

Spawn of Rix Maadi

Unleash (You may have this creature enter with a +1/+1 counter on it. It can't block as long as it has a +1/+1 counter on it.)

Skull Rend

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

Skewer the Critics

Spectacle {R} (You may cast this spell for its spectacle cost rather than its mana cost if an opponent lost life this turn.)
Skewer the Critics deals 3 damage to any target.

Mayhem Devil

Whenever a player sacrifices a permanent, this creature deals 1 damage to any target.

Master of Cruelties

First strike, deathtouch
This creature can only attack alone.
Whenever this creature attacks a player and isn't blocked, that player's life total becomes 1. This creature assigns no combat damage this combat.

Demolish

Rakdos Cackler

Rakdos Guildgate

This land enters tapped.
{T}: Add {B} or {R}.

Rakdos Cluestone

{T}: Add {B} or {R}.
{B}{R}, {T}, Sacrifice this artifact: Draw a card.

Bloodfray Giant

Trample
Unleash (You may have this creature enter with a +1/+1 counter on it. It can't block as long as it has a +1/+1 counter on it.)

Daggerdrome Imp

Flying
Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Pyroconvergence

Whenever you cast a multicolored spell, this enchantment deals 2 damage to any target.

Macabre Mockery

Put target creature card from an opponent's graveyard onto the battlefield under your control. It gets +2/+0 and gains haste until end of turn. Sacrifice it at the beginning of the next end step.

Rakdos Shred-Freak

Sire of Insanity

At the beginning of each end step, each player discards their hand.

Last Gasp

Target creature gets -3/-3 until end of turn.

Rakdos Pit Dragon

{R}{R}: This creature gains flying until end of turn.
{R}: This creature gets +1/+0 until end of turn.
Hellbent — This creature has double strike as long as you have no cards in hand.

Sol Ring

Act of Treason

Gain control of target creature until end of turn. Untap that creature. It gains haste until end of turn. (It can attack and {T} this turn.)

Rakdos Guildmage

({B/R} can be paid with either {B} or {R}.)
{3}{B}, Discard a card: Target creature gets -2/-2 until end of turn.
{3}{R}: Create a 2/1 red Goblin creature token with haste. Exile it at the beginning of the next end step.

Rakdos Locket

{T}: Add {B} or {R}.
{B/R}{B/R}{B/R}{B/R}, {T}, Sacrifice this artifact: Draw two cards.

Taste for Mayhem

Enchant creature
Enchanted creature gets +2/+0.
Hellbent — Enchanted creature gets an additional +2/+0 as long as you have no cards in hand.

Perforating Artist

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
Raid — At the beginning of your end step, if you attacked this turn, each opponent loses 3 life unless that player sacrifices a nonland permanent of their choice or discards a card.

Rakdos Keyrune

{T}: Add {B} or {R}.
{B}{R}: This artifact becomes a 3/1 black and red Devil artifact creature with first strike until end of turn.

Black Waltz No. 3

Flying, deathtouch
Whenever you cast a noncreature spell, Black Waltz No. 3 deals 2 damage to each opponent.

Dreadbore

Massacre Girl

Menace
When Massacre Girl enters, each other creature gets -1/-1 until end of turn. Whenever a creature dies this turn, each creature other than Massacre Girl gets -1/-1 until end of turn.

Bedazzle

Destroy target nonbasic land. Bedazzle deals 2 damage to target opponent or planeswalker.

Bedeck

Target creature gets +3/-3 until end of turn.

Bedeck // Bedazzle

Launch Party

As an additional cost to cast this spell, sacrifice a creature.
Destroy target creature. Its controller loses 2 life.

Auger Spree

Target creature gets +4/-4 until end of turn.

Silent Dart

{4}, {T}, Sacrifice this artifact: It deals 3 damage to target creature.

Showstopper

Until end of turn, creatures you control gain "When this creature dies, it deals 2 damage to target creature an opponent controls."

Chaos Imps

Flying
Unleash (You may have this creature enter with a +1/+1 counter on it. It can't block as long as it has a +1/+1 counter on it.)
This creature has trample as long as it has a +1/+1 counter on it.

Madcap Skills

Enchant creature
Enchanted creature gets +3/+0 and has menace.

Mugging

Mugging deals 2 damage to target creature. That creature can't block this turn.

Gobhobbler Rats

Hellbent — As long as you have no cards in hand, this creature gets +1/+0 and has "{B}: Regenerate this creature." (The next time it would be destroyed this turn, instead tap it, remove it from combat, and heal all damage on it.)

Drill Bit

Spectacle {B} (You may cast this spell for its spectacle cost rather than its mana cost if an opponent lost life this turn.)
Target player reveals their hand. You choose a nonland card from it. That player discards that card.

Blade Juggler

Spectacle {2}{B} (You may cast this spell for its spectacle cost rather than its mana cost if an opponent lost life this turn.)
When this creature enters, it deals 1 damage to you and you draw a card.

Woebringer Demon

Flying
At the beginning of each player's upkeep, that player sacrifices a creature of their choice. If the player can't, sacrifice this creature.

Fireblade Artist

Haste
At the beginning of your upkeep, you may sacrifice a creature. When you do, this creature deals 2 damage to target opponent or planeswalker.

Rix Maadi Guildmage

{B}{R}: Target blocking creature gets -1/-1 until end of turn.
{B}{R}: Target player who lost life this turn loses 1 life.

Stalking Vengeance

Haste
Whenever another creature you control dies, it deals damage equal to its power to target player or planeswalker.

Fireshrieker

Equipped creature has double strike. (It deals both first-strike and regular combat damage.)
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Swamp

Chaos, the Endless

Flying
When Chaos dies, put it on the bottom of its owner's library.

Garland, Knight of Cornelia

Whenever you cast a noncreature spell, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)
{3}{B}{B}{R}{R}: Return this card from your graveyard to the battlefield transformed. Activate only as a sorcery.

Garland, Knight of Cornelia // Chaos, the Endless

Skullcrack

Players can't gain life this turn. Damage can't be prevented this turn. Skullcrack deals 3 damage to target player or planeswalker.

Mountain

Carnage Gladiator

Whenever a creature blocks, that creature's controller loses 1 life.
{1}{B}{R}: Regenerate this creature.

Rakdos Trumpeter

Menace (This creature can't be blocked except by two or more creatures.)
{3}{R}: This creature gets +2/+0 until end of turn.

Gore-House Chainwalker

Trouble

Trouble deals damage to target player equal to the number of cards in that player's hand.
Fuse (You may cast one or both halves of this card from your hand.)

Toil

Target player draws two cards and loses 2 life.
Fuse (You may cast one or both halves of this card from your hand.)

Toil // Trouble

Blood Crypt

({T}: Add {B} or {R}.)
As this land enters, you may pay 2 life. If you don't, it enters tapped.

Annihilating Fire

Annihilating Fire deals 3 damage to any target. If a creature dealt damage this way would die this turn, exile it instead.

Rakdos Signet

Splatter Thug

First strike
Unleash (You may have this creature enter with a +1/+1 counter on it. It can't block as long as it has a +1/+1 counter on it.)

Bladebrand

Target creature gains deathtouch until end of turn.
Draw a card.

Cryptborn Horror

Trample
This creature enters with X +1/+1 counters on it, where X is the total life lost by your opponents this turn.

Thrill-Kill Assassin

Deathtouch
Unleash (You may have this creature enter with a +1/+1 counter on it. It can't block as long as it has a +1/+1 counter on it.)

Footlight Fiend

When this creature dies, it deals 1 damage to any target.

Demonfire

Demonfire deals X damage to any target. If a creature dealt damage this way would die this turn, exile it instead.
Hellbent — If you have no cards in hand, this spell can't be countered and the damage can't be prevented.