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.

Warstorm Surge

Whenever a creature enters the battlefield under your control, it deals damage equal to its power to any target.

Skirsdag High Priest

Morbid — {T}, Tap two untapped creatures you control: Create a 5/5 black Demon creature token with flying. Activate only if a creature died this turn.

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.

Kill! Maim! Burn!

Choose one or more —
• Destroy target artifact.
• Destroy target creature.
• Kill! Maim! Burn! deals 3 damage to target player.

Master of Cruelties

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

Command Tower

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

Nurgle's Conscription

Put target creature card from an opponent's graveyard onto the battlefield tapped under your control, then exile that player's graveyard.

Chaos Defiler

Trample
Battle Cannon — When Chaos Defiler enters the battlefield or dies, for each opponent, choose a nonland permanent that player controls. Destroy one of them chosen at random.

Reverberate

Copy target instant or sorcery spell. You may choose new targets for the copy.

Pink Horror

Coruscating Flames — Whenever you cast an instant or sorcery spell, Pink Horror deals 2 damage to any target.
Split — When Pink Horror dies, create two 2/2 blue and red Demon Horror creature tokens named Blue Horror with "Whenever you cast an instant or sorcery spell, this creature deals 1 damage to any target."

Argentum Armor

Equipped creature gets +6/+6.
Whenever equipped creature attacks, destroy target permanent.
Equip {6}

Heralds of Tzeentch

Flying
Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom of your library in a random order.)

Worn Powerstone

Worn Powerstone enters the battlefield tapped.
{T}: Add {C}{C}.

Reflections of Littjara

As Reflections of Littjara enters the battlefield, choose a creature type.
Whenever you cast a spell of the chosen type, copy that spell. (A copy of a permanent spell becomes a token.)

Blade of the Oni

Menace
Equipped creature has base power and toughness 5/5, has menace, and is a black Demon in addition to its other colors and types.
Reconfigure {2}{B}{B} ({2}{B}{B}: Attach to target creature you control; or unattach from a creature. Reconfigure only as a sorcery. While attached, this isn't a creature.)

Hammer of Nazahn

Whenever Hammer of Nazahn or another Equipment enters the battlefield under your control, you may attach that Equipment to target creature you control.
Equipped creature gets +2/+0 and has indestructible.
Equip {4}

Echo Storm

When you cast this spell, copy it for each time you've cast your commander from the command zone this game. You may choose new targets for the copies.
Create a token that's a copy of target artifact.

Herald's Horn

As Herald's Horn enters the battlefield, choose a creature type.
Creature spells you cast of the chosen type cost {1} less to cast.
At the beginning of your upkeep, look at the top card of your library. If it's a creature card of the chosen type, you may reveal it and put it into your hand.

Conqueror's Flail

Equipped creature gets +1/+1 for each color among permanents you control.
As long as Conqueror's Flail is attached to a creature, your opponents can't cast spells during your turn.
Equip {2}

Priest of the Blood Rite

When Priest of the Blood Rite enters the battlefield, create a 5/5 black Demon creature token with flying.
At the beginning of your upkeep, you lose 2 life.

Role Reversal

Exchange control of two target permanents that share a permanent type.

Command Beacon

{T}: Add {C}.
{T}, Sacrifice Command Beacon: Put your commander into your hand from the command zone.

Armillary Sphere

{2}, {T}, Sacrifice Armillary Sphere: Search your library for up to two basic land cards, reveal them, put them into your hand, then shuffle.

Burning Anger

Enchant creature
Enchanted creature has "{T}: This creature deals damage equal to its power to any target."

Sol Ring

Dark Ritual

Mirror Image

You may have Mirror Image enter the battlefield as a copy of a creature you control.

Magnus the Red

Flying
Unearthly Power — Instant and sorcery spells you cast cost {1} less to cast for each creature token you control.
Blade of Magnus — Whenever Magnus the Red deals combat damage to a player, create a 3/3 red Spawn creature token.

Crystal Grotto

When Crystal Grotto enters the battlefield, scry 1.
{T}: Add {C}.
{1}, {T}: Add one mana of any color.

Great Unclean One

Reverberating Summons — At the beginning of your end step, each opponent loses 2 life. Then for each opponent who has less life than you, create a 1/3 black Demon creature token named Plaguebearer of Nurgle.

Lord of the Void

Flying
Whenever Lord of the Void deals combat damage to a player, exile the top seven cards of that player's library, then put a creature card from among them onto the battlefield under your control.

Archfiend of Despair

Flying
Your opponents can't gain life.
At the beginning of each end step, each opponent loses life equal to the life that player lost this turn. (Damage causes loss of life.)

Brainstorm

Draw three cards, then put two cards from your hand on top of your library in any order.

Fiendlash

Equipped creature gets +2/+0 and has reach.
Whenever equipped creature is dealt damage, it deals damage equal to its power to target player or planeswalker.
Equip {2}{R}

Haunted One

Commander creatures you own have "Whenever this creature becomes tapped, it and other creatures you control that share a creature type with it each get +2/+0 and gain undying until end of turn." (When a creature with undying 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.)

Basilisk Collar

Equipped creature has deathtouch and lifelink.
Equip {2}

Bloodcrusher of Khorne

Trample
Devastating Charge — Other creatures you control have trample.

Blood Crypt

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

The Horus Heresy

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — For each opponent, gain control of up to one target nonlegendary creature that player controls for as long as The Horus Heresy remains on the battlefield.
II — Draw a card for each creature you control but don't own.
III — Starting with you, each player chooses a creature. Destroy each creature chosen this way.

Embodiment of Agonies

Flying, deathtouch
Embodiment of Agonies enters the battlefield with a +1/+1 counter on it for each different mana cost among nonland cards in your graveyard. (For example, {2}{B} and {1}{B}{B} are different mana costs.)

Chromatic Lantern

Lands you control have "{T}: Add one mana of any color."
{T}: Add one mana of any color.

Lord of Change

Flying, ward {3}
Architect of Deception — When Lord of Change enters the battlefield, draw three cards.

Exalted Flamer of Tzeentch

Sorcerous Inspiration — At the beginning of your upkeep, return an instant or sorcery card at random from your graveyard to your hand.
Fire of Tzeentch — Whenever you cast an instant or sorcery spell, Exalted Flamer of Tzeentch deals 1 damage to each opponent.

Swamp

Bile Blight

Target creature and all other creatures with the same name as that creature get -3/-3 until end of turn.

Soulcage Fiend

When Soulcage Fiend dies, each player loses 3 life.

Keeper of Secrets

First strike, haste
Symphony of Pain — Whenever you cast a spell from anywhere other than your hand, Keeper of Secrets deals damage equal to that spell's mana value to target opponent.

Seeker of Slaanesh

Haste
Allure of Slaanesh — Each opponent must attack with at least one creature each combat if able.

Demon of Death's Gate

You may pay 6 life and sacrifice three black creatures rather than pay this spell's mana cost.
Flying, trample

Gem of Becoming

{3}, {T}, Sacrifice Gem of Becoming: Search your library for an Island card, a Swamp card, and a Mountain card. Reveal those cards, put them into your hand, then shuffle.

Temple of Epiphany

Temple of Epiphany enters the battlefield tapped.
When Temple of Epiphany enters the battlefield, scry 1.
{T}: Add {U} or {R}.

Chaos Mutation

Exile any number of target creatures controlled by different players. For each creature exiled this way, its controller reveals cards from the top of their library until they reveal a creature card, puts that card onto the battlefield, then puts the rest on the bottom of their library in a random order.

Metamorphic Alteration

Enchant creature
As Metamorphic Alteration enters the battlefield, choose a creature.
Enchanted creature is a copy of the chosen creature.

Be'lakor, the Dark Master

Flying
Prince of Chaos — When Be'lakor, the Dark Master enters the battlefield, you draw X cards and you lose X life, where X is the number of Demons you control.
Lord of Torment — Whenever another Demon enters the battlefield under your control, it deals damage equal to its power to any target.

Bonesplitter

Rakdos, the Showstopper

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

The Ruinous Powers

At the beginning of your upkeep, choose an opponent at random. Exile the top card of that player's library. Until end of turn, you may play that card and you may spend mana as though it were mana of any color to cast it. When you cast a spell this way, its owner loses life equal to its mana value.

Bituminous Blast

Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom of your library in a random order.)
Bituminous Blast deals 4 damage to target creature.

Plague Drone

Flying
Rot Fly — If an opponent would gain life, that player loses that much life instead.

Mountain

Lord Xander, the Collector

When Lord Xander, the Collector enters the battlefield, target opponent discards half the cards in their hand, rounded down.
Whenever Lord Xander attacks, defending player mills half their library, rounded down.
When Lord Xander dies, target opponent sacrifices half the nonland permanents they control, rounded down.

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 Decree of Pain, all creatures get -2/-2 until end of turn.

Javelin of Lightning

Flash
When Javelin of Lightning enters the battlefield, attach it to target creature you control.
As long as it's your turn, equipped creature gets +2/+0 and has first strike.
Equip {4} ({4}: Attach to target creature you control. Equip only as a sorcery.)

Double Vision

Whenever you cast your first instant or sorcery spell each turn, copy that spell. You may choose new targets for the copy.

Bloodthirster

Flying, trample
Whenever Bloodthirster deals combat damage to a player, untap it. After this combat phase, there is an additional combat phase.
Bloodthirster can't attack a player it has already attacked this turn.

Herald of Slaanesh

Locus of Slaanesh — Demon spells you cast cost {2} less to cast.
Other Demons you control have haste.

Nurgle's Rot

Enchant creature an opponent controls
When enchanted creature dies, return Nurgle's Rot to its owner's hand and you create a 1/3 black Demon creature token named Plaguebearer of Nurgle.

Demon of Catastrophes

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

Blood for the Blood God!

This spell costs {1} less to cast for each creature that died this turn.
Discard your hand, then draw eight cards. Blood for the Blood God! deals 8 damage to each opponent. Exile Blood for the Blood God!

Balor

Flying
Whenever Balor attacks or dies, choose one or more. Each mode must target a different player.
• Target opponent draws three cards, then discards three cards at random.
• Target opponent sacrifices a nontoken artifact.
• Balor deals damage to target opponent equal to the number of cards in their hand.

Island

Kardur, Doomscourge

When Kardur, Doomscourge enters the battlefield, 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.