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.

Rakdos, the Showstopper

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

Sol Ring

Terminate

Destroy target creature. It can't be regenerated.

Spiteful Visions

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

Worn Powerstone

This artifact enters tapped.
{T}: Add {C}{C}.

Bloodfell Caves

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

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.

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."

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.

Undying Evil

Target creature gains undying until end of turn. (When it dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)

Stab Wound

Enchant creature
Enchanted creature gets -2/-2.
At the beginning of the upkeep of enchanted creature's controller, that player loses 2 life.

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.

Captive Audience

This enchantment 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.

Overseer of the Damned

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

Horn of Plenty

Whenever a player casts a spell, they may pay {1}. If the player does, they draw a card at the beginning of the next end step.

Ob Nixilis Reignited

+1: You draw a card and you lose 1 life.
−3: Destroy target creature.
−8: Target opponent gets an emblem with "Whenever a player draws a card, you lose 2 life."

Blasphemous Act

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

Exhume

Each player puts a creature card from their graveyard onto the battlefield.

Pain's Reward

Each player may bid life. You start the bidding with a bid of any number. In turn order, each player may top the high bid. The bidding ends if the high bid stands. The high bidder loses life equal to the high bid and draws four cards.

Rite of the Raging Storm

Creatures named Lightning Rager can't attack you or planeswalkers you control.
At the beginning of each player's upkeep, that player creates a 5/1 red Elemental creature token named Lightning Rager. It has trample, haste, and "At the beginning of the end step, sacrifice this token."

Fetid Imp

Flying
{B}: This creature gains deathtouch until end of turn. (Any amount of damage it deals to a creature is enough to destroy it.)

Witch Hunt

Players can't gain life.
At the beginning of your upkeep, this enchantment deals 4 damage to you.
At the beginning of your end step, target opponent chosen at random gains control of this enchantment.

Akroan Horse

Defender
When this creature enters, an opponent gains control of it.
At the beginning of your upkeep, each opponent creates a 1/1 white Soldier creature token.

Last One Standing

Choose a creature at random, then destroy the rest.

Liliana's Contract

When this enchantment enters, you draw four cards and you lose 4 life.
At the beginning of your upkeep, if you control four or more Demons with different names, you win the game.

Soulcage Fiend

When this creature dies, each player loses 3 life.

Reassembling Skeleton

{1}{B}: Return this card from your graveyard to the battlefield tapped.

Akoum Refuge

Hissing Miasma

Whenever a creature attacks you, its controller loses 1 life.

Command Tower

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

Hedron Archive

{T}: Add {C}{C}.
{2}, {T}, Sacrifice this artifact: Draw two cards.

Goblin Kaboomist

At the beginning of your upkeep, create a colorless artifact token named Land Mine with "{R}, Sacrifice this token: This token deals 2 damage to target attacking creature without flying." Then flip a coin. If you lose the flip, this creature deals 2 damage to itself.

Quest for the Gravelord

Whenever a creature dies, you may put a quest counter on this enchantment.
Remove three quest counters from this enchantment and sacrifice it: Create a 5/5 black Zombie Giant creature token.

Kothophed, Soul Hoarder

Flying
Whenever a permanent owned by another player is put into a graveyard from the battlefield, you draw a card and you lose 1 life.

Reiver Demon

Flying
When this creature enters, if you cast it from your hand, destroy all nonartifact, nonblack creatures. They can't be regenerated.

Vivid Marsh

This land enters tapped with two charge counters on it.
{T}: Add {B}.
{T}, Remove a charge counter from this land: Add one mana of any color.

Swamp

Syphon Mind

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

Rakdos's Return

Rakdos's Return deals X damage to target opponent or planeswalker. That player or that planeswalker's controller discards X cards.

Dismember

({B/P} can be paid with either {B} or 2 life.)
Target creature gets -5/-5 until end of turn.

Vivid Crag

This land enters tapped with two charge counters on it.
{T}: Add {R}.
{T}, Remove a charge counter from this land: Add one mana of any color.

Underworld Dreams

Whenever an opponent draws a card, this enchantment deals 1 damage to that player.

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.

Evolving Wilds

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

Xantcha, Sleeper Agent

Xantcha enters under the control of an opponent of your choice.
Xantcha attacks each combat if able and can't attack its owner or planeswalkers its owner controls.
{3}: Xantcha's controller loses 2 life and you draw a card. Any player may activate this ability.

Sin Prodder

Menace
At the beginning of your upkeep, reveal the top card of your library. Any opponent may have you put that card into your graveyard. If a player does, this creature deals damage to that player equal to that card's mana value. Otherwise, put that card into your hand.

Enslaved Horror

When this creature enters, each other player may return a creature card from their graveyard to the battlefield.

Reaper from the Abyss

Flying
Morbid — At the beginning of each end step, if a creature died this turn, destroy target non-Demon creature.

Allure of the Unknown

Reveal the top six cards of your library. An opponent exiles a nonland card from among them, then you put the rest into your hand. That opponent may cast the exiled card without paying its mana cost.

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.

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice this artifact: Draw a card.

Dread Cacodemon

When this creature enters, if you cast it from your hand, destroy all creatures your opponents control, then tap all other creatures you control.

Tempt with Immortality

Tempting offer — Return a creature card from your graveyard to the battlefield. Each opponent may return a creature card from their graveyard to the battlefield. For each opponent who does, return a creature card from your graveyard to the battlefield.

Crown of Doom

Whenever a creature attacks you or a planeswalker you control, it gets +2/+0 until end of turn.
{2}: Target player other than this artifact's owner gains control of it. Activate only during your turn.

Helm of Awakening

Demon of Catastrophes

As an additional cost to cast this spell, sacrifice a creature.
Flying, trample

Torch Fiend

{R}, Sacrifice this creature: Destroy target artifact.

Killing Wave

For each creature, its controller sacrifices it unless they pay X life.

Sower of Discord

Flying
As this creature enters, choose two players.
Whenever damage is dealt to one of the chosen players, the other chosen player also loses that much life.

Mountain

Rakdos Guildgate

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

Teferi's Puzzle Box

At the beginning of each player's draw step, that player puts the cards in their hand on the bottom of their library in any order, then draws that many cards.

Shadowborn Demon

Flying
When this creature enters, destroy target non-Demon creature.
At the beginning of your upkeep, if there are fewer than six creature cards in your graveyard, sacrifice a creature.

Everflowing Chalice

Multikicker {2} (You may pay an additional {2} any number of times as you cast this spell.)
This artifact enters with a charge counter on it for each time it was kicked.
{T}: Add {C} for each charge counter on this artifact.

Doom Blade

Reign of the Pit

Each player sacrifices a creature of their choice. Create an X/X black Demon creature token with flying, where X is the total power of the creatures sacrificed this way.

Terramorphic Expanse

Whip of Erebos

Creatures you control have lifelink.
{2}{B}{B}, {T}: Return target creature card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step. If it would leave the battlefield, exile it instead of putting it anywhere else. Activate only as a sorcery.

Talisman of Indulgence

{T}: Add {C}.
{T}: Add {B} or {R}. This artifact deals 1 damage to you.

Curse of Opulence

Enchant player
Whenever enchanted player is attacked, create a Gold token. Each opponent attacking that player does the same. (A Gold token is an artifact with "Sacrifice this token: Add one mana of any color.")

Blood Speaker

At the beginning of your upkeep, you may sacrifice this creature. If you do, search your library for a Demon card, reveal that card, put it into your hand, then shuffle.
Whenever a Demon you control enters, return this card from your graveyard to your hand.

Rakdos Carnarium

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

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 this card, all creatures get -2/-2 until end of turn.

Rakdos Locket

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

Virtus's Maneuver

For each player, choose friend or foe. Each friend returns a creature card from their graveyard to their hand. Each foe sacrifices a creature of their choice.