Nefarox, Overlord of Grixis

Flying
Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.)
Whenever Nefarox attacks alone, defending player sacrifices a creature of their choice.

Let the Galaxy Burn

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 in a random order.)
Let the Galaxy Burn deals X plus 2 damage to each creature that didn't enter this turn.

Inner Demon

Enchant creature
Enchanted creature gets +2/+2, has flying, and is a Demon in addition to its other types.
When this Aura enters, all non-Demon creatures get -2/-2 until end of turn.

Kardur, Doomscourge

When Kardur 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.

Evolving Wilds

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

Reaper from the Abyss

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

Gyruda, Doom of Depths

Companion — Your starting deck contains only cards with even mana values. (If this card is your chosen companion, you may put it into your hand from outside the game for {3} as a sorcery.)
When Gyruda enters, each player mills four cards. Put a creature card with an even mana value from among the milled cards onto the battlefield under your control.

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.

Rakdos Carnarium

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

Rakdos Signet

Inherited Fiend

Flying
{2}{B}: Exile target creature card from a graveyard. Put a +1/+1 counter on this creature.

Heirloom Mirror

{1}, {T}, Pay 1 life, Discard a card: Draw a card, mill a card, then put a ritual counter on this artifact. Then if it has three or more ritual counters on it, remove them and transform it. Activate only as a sorcery.

Heirloom Mirror // Inherited Fiend

Harvester of Souls

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
Whenever another nontoken creature dies, you may draw a card.

Mountain

Dimir Signet

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control. It can attack and {T} no matter when it came under your control.)
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Demonlord of Ashmouth

Flying
When this creature enters, exile it unless you sacrifice another creature.
Undying (When this creature 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.)

Devils' Playground

Create four 1/1 red Devil creature tokens. They have "When this token dies, it deals 1 damage to any target."

Planar Incision

Exile target artifact or creature, then return it to the battlefield under its owner's control with a +1/+1 counter on it.

Forgotten Cave

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

Persist

Return target nonlegendary creature card from your graveyard to the battlefield with a -1/-1 counter on it.

Temple of the False God

{T}: Add {C}{C}. Activate only if you control five or more lands.

Sloppity Bilepiper

Jolly Gutpipes — {2}, {T}, Sacrifice a creature: The next creature spell you cast this turn has cascade. (When you next cast a creature 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 in a random order.)

Heartless Summoning

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

Tyrannical Pitlord

Flying, trample
As this creature enters, choose another creature you control.
The chosen creature gets +3/+3 and has flying.
When this creature leaves the battlefield, sacrifice the chosen creature.

Warstorm Surge

Whenever a creature you control enters, it deals damage equal to its power to any target.

Bile Blight

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

Malfegor

Flying
When Malfegor enters, discard your hand. Each opponent sacrifices a creature of their choice for each card discarded this way.

Venomcrawler

Lifelink
Devourer of Souls — Whenever another creature dies, put a +1/+1 counter on this creature.

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.

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.

Rakshasa Debaser

Whenever this creature attacks, put target creature card from defending player's graveyard onto the battlefield under your control.
Encore {6}{B}{B} ({6}{B}{B}, Exile this card from your graveyard: For each opponent, create a token copy that attacks that opponent this turn if able. They gain haste. Sacrifice them at the beginning of the next end step. Activate only as a sorcery.)

Infernal Grasp

Destroy target creature. You lose 2 life.

Carnifex Demon

Flying
This creature enters with two -1/-1 counters on it.
{B}, Remove a -1/-1 counter from this creature: Put a -1/-1 counter on each other creature.

Drach'Nyen

Echo of the First Murder — When Drach'Nyen enters, exile up to one target creature.
Daemon Sword — Equipped creature has menace and gets +X/+0, where X is the exiled card's power.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

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.

Myriad Landscape

This land enters tapped.
{T}: Add {C}.
{2}, {T}, Sacrifice this land: Search your library for up to two basic land cards that share a land type, put them onto the battlefield tapped, then shuffle.

Demonlord Belzenlok

Flying, trample
When Demonlord Belzenlok enters, exile cards from the top of your library until you exile a nonland card, then put that card into your hand. If the card's mana value is 4 or greater, repeat this process. Demonlord Belzenlok deals 1 damage to you for each card put into your hand this way.

Big Score

As an additional cost to cast this spell, discard a card.
Draw two cards and create two Treasure tokens. (They're artifacts with "{T}, Sacrifice this token: Add one mana of any color.")

Orcus, Prince of Undeath

Flying, trample
When Orcus enters, choose one —
• Each other creature gets -X/-X until end of turn. You lose X life.
• Return up to X target creature cards with total mana value X or less from your graveyard to the battlefield. They gain haste until end of turn.

Arcane Denial

Counter target spell. Its controller may draw up to two cards at the beginning of the next turn's upkeep.
You draw a card at the beginning of the next turn's upkeep.

Immersturm Raider

When this creature enters, you may discard a card. If you do, draw a card.

Lost Vale

(Transforms from Dowsing Dagger.)
{T}: Add three mana of any one color.

Dowsing Dagger

When this Equipment enters, target opponent creates two 0/2 green Plant creature tokens with defender.
Equipped creature gets +2/+1.
Whenever equipped creature deals combat damage to a player, you may transform this Equipment.
Equip {2}

Dowsing Dagger // Lost Vale

Rafter Demon

Spectacle {3}{B}{R} (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, if its spectacle cost was paid, each opponent discards a card.

Sunken Hollow

({T}: Add {U} or {B}.)
This land enters tapped unless you control two or more basic lands.

Plague Drone

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

Cabal Stronghold

{T}: Add {C}.
{3}, {T}: Add {B} for each basic Swamp you control.

Desecration Demon

Flying
At the beginning of each combat, any opponent may sacrifice a creature of their choice. If a player does, tap this creature and put a +1/+1 counter on it.

Molten Slagheap

{T}: Add {C}.
{1}, {T}: Put a storage counter on this land.
{1}, Remove X storage counters from this land: Add X mana in any combination of {B} and/or {R}.

Izzet Signet

Seeker of Slaanesh

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

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.

Dimir Aqueduct

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

Teferi's Time Twist

Exile target permanent you control. Return that card to the battlefield under its owner's control at the beginning of the next end step. If it enters as a creature, it enters with an additional +1/+1 counter on it.

Mandate of Abaddon

Choose target creature you control. Destroy all creatures with power less than that creature's power.

Illusionist's Stratagem

Exile up to two target creatures you control, then return those cards to the battlefield under their owner's control.
Draw a card.

Barren Moor

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

Smoldering Marsh

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

Bloodcrusher of Khorne

Trample
Devastating Charge — Other creatures you control have trample.

Crumbling Necropolis

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

Sol Ring

Dwarven Reinforcements

Create two 2/1 red Dwarf Berserker creature tokens.
Foretell {1}{R} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

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.)

Demon of Catastrophes

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

Abrade

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

Swamp

Dragon Fodder

Create two 1/1 red Goblin creature tokens.

Terminate

Destroy target creature. It can't be regenerated.

Kindred Charge

Choose a creature type. For each creature you control of the chosen type, create a token that's a copy of that creature. Those tokens gain haste. Exile them at the beginning of the next end step.

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.

Dack's Duplicate

You may have this creature enter as a copy of any creature on the battlefield, except it has haste and dethrone. (Whenever it attacks the player with the most life or tied for most life, put a +1/+1 counter on it.)

Exotic Orchard

{T}: Add one mana of any color that a land an opponent controls could produce.

Daxos's Torment

Constellation — Whenever this enchantment or another enchantment you control enters, this enchantment becomes a 5/5 Demon creature with flying and haste in addition to its other types until end of turn.

Conductor of Cacophony

This creature enters with two +1/+1 counters on it.
{B}, Remove a +1/+1 counter from this creature: It deals 1 damage to each other creature and each player.

Molten Echoes

As this enchantment enters, choose a creature type.
Whenever a nontoken creature you control of the chosen type enters, create a token that's a copy of that creature. That token gains haste. Exile it at the beginning of the next end step.

Elemental Mastery

Enchant creature
Enchanted creature has "{T}: Create X 1/1 red Elemental creature tokens with haste, where X is this creature's power. Exile them at the beginning of the next end step."

Foreboding Ruins

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

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.)

Nightmare Shepherd

Flying
Whenever another nontoken creature you control dies, you may exile it. If you do, create a token that's a copy of that creature, except it's 1/1 and it's a Nightmare in addition to its other types.

Dance with Devils

Create two 1/1 red Devil creature tokens. They have "When this token dies, it deals 1 damage to any target."

Command Tower

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

Reiver Demon

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

Izzet Boilerworks

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