Command Tower

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

Mountain

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.

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.

Swamp

Chaos Defiler

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

Steam Vents

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

Rite of Replication

Kicker {5} (You may pay an additional {5} as you cast this spell.)
Create a token that's a copy of target creature. If this spell was kicked, create five of those tokens instead.

Island

Valgavoth, Terror Eater

Flying, lifelink
Ward—Sacrifice three nonland permanents.
If a card you didn't control would be put into an opponent's graveyard from anywhere, exile it instead.
During your turn, you may play cards exiled with Valgavoth. If you cast a spell this way, pay life equal to its mana value rather than pay its mana cost.

Blood Crypt

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

Urza's Incubator

As this artifact enters, choose a creature type.
Creature spells of the chosen type cost {2} less to cast.

Bloodthirster

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

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.

Patriarch's Bidding

Each player chooses a creature type. Each player returns all creature cards of a type chosen this way from their graveyard to the battlefield.

Ritual Chamber

When you unlock this door, create a 6/6 black Demon creature token with flying.
(You may cast either half. That door unlocks on the battlefield. As a sorcery, you may pay the mana cost of a locked door to unlock it.)

Unholy Annex

At the beginning of your end step, draw a card. If you control a Demon, each opponent loses 2 life and you gain 2 life. Otherwise, you lose 2 life.
(You may cast either half. That door unlocks on the battlefield. As a sorcery, you may pay the mana cost of a locked door to unlock it.)

Unholy Annex // Ritual Chamber

Be'lakor, the Dark Master

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

Herald's Horn

As this artifact enters, 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.

Reflections of Littjara

As this enchantment enters, 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.)

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.

Demonic Counsel

Search your library for a Demon card, reveal it, put it into your hand, then shuffle.
Delirium — If there are four or more card types among cards in your graveyard, instead search your library for any card, put it into your hand, then shuffle.

Herald of Slaanesh

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

Watery Grave

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

Dream Devourer

Each nonland card in your hand without foretell has foretell. Its foretell cost is equal to its mana cost reduced by {2}. (During your turn, you may pay {2} and exile it from your hand face down. Cast it on a later turn for its foretell cost.)
Whenever you foretell a card, this creature gets +2/+0 until end of turn.

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.

The Balrog of Moria

Trample, haste
When The Balrog of Moria dies, you may exile it. When you do, for each opponent, exile up to one target creature that player controls.
Cycling {3}{R} ({3}{R}, Discard this card: Draw a card.)
When you cycle this card, create two Treasure tokens.

Roaming Throne

Ward {2}
As this creature enters, choose a creature type.
This creature is the chosen type in addition to its other types.
If a triggered ability of another creature you control of the chosen type triggers, it triggers an additional time.

Rakdos Signet

Path of Ancestry

This land 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.)

Heartless Summoning

Creature spells you cast cost {2} less to cast.
Creatures you control get -1/-1.

Ancient Cellarspawn

Each spell you cast that's a Demon, Horror, or Nightmare costs {1} less to cast.
Whenever you cast a spell, if the amount of mana spent to cast it was less than its mana value, target opponent loses life equal to the difference.

Lord of Change

Flying, ward {3}
Architect of Deception — When this creature enters, draw three cards.

Relic of Sauron

{T}: Add two mana in any combination of {U}, {B}, and/or {R}.
{3}, {T}: Draw two cards, then discard a card.

Xander's Lounge

({T}: Add {U}, {B}, or {R}.)
This land enters tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Varragoth, Bloodsky Sire

Deathtouch
Boast — {1}{B}: Target player searches their library for a card, then shuffles and puts that card on top. (Activate only if this creature attacked this turn and only once each turn.)

Balor

Flying
Whenever this creature 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 of their choice.
• This creature deals damage to target opponent equal to the number of cards in their hand.