Tiamat's Fanatics

Haste
Myriad (Whenever this creature attacks, for each opponent other than defending player, you may create a token copy that's tapped and attacking that player or a planeswalker they control. Exile the tokens at end of combat.)

Territory Forge

When this artifact enters, if you cast it, exile target artifact or land.
This artifact has all activated abilities of the exiled card.

Arcane Signet

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

Copy

(This token can be used to represent a token that's a copy of a permanent.)

Luxury Suite

This land enters tapped unless you have two or more opponents.
{T}: Add {B} or {R}.

Goblin Bombardment

Sacrifice a creature: This enchantment deals 1 damage to any target.

Parasitic Impetus

Enchant creature
Enchanted creature gets +2/+2 and is goaded. (It attacks each combat if able and attacks a player other than you if able.)
Whenever enchanted creature attacks, its controller loses 2 life and you gain 2 life.

Conduit Pylons

When this land enters, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)
{T}: Add {C}.
{1}, {T}: Add one mana of any color.

Faithless Looting

Draw two cards, then discard two cards.
Flashback {2}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Body Dropper

Whenever you sacrifice another creature, put a +1/+1 counter on this creature.
{B}{R}, Sacrifice another creature: This creature gains menace until end of turn. (It can't be blocked except by two or more creatures.)

Temple of the False God

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

Reaper from the Abyss

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

Make Mischief

Make Mischief deals 1 damage to any target. Create a 1/1 red Devil creature token. It has "When this token dies, it deals 1 damage to any target."

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.

Maskwood Nexus

Creatures you control are every creature type. The same is true for creature spells you control and creature cards you own that aren't on the battlefield.
{3}, {T}: Create a 2/2 blue Shapeshifter creature token with changeling. (It is every creature type.)

Reflecting Pool

{T}: Add one mana of any type that a land you control could produce.

Thunderwave

Roll a d20.
1—9 | Thunderwave deals 3 damage to each creature.
10—19 | You may choose a creature. Thunderwave deals 3 damage to each creature not chosen this way.
20 | Thunderwave deals 6 damage to each creature your opponents control.

Buried Ruin

{T}: Add {C}.
{2}, {T}, Sacrifice this land: Return target artifact card from your graveyard to your hand.

Agent of the Shadow Thieves

Commander creatures you own have "Whenever this creature attacks a player, if no opponent has more life than that player, put a +1/+1 counter on this creature. It gains deathtouch and indestructible until end of turn."

Consuming Ashes

Exile target creature. If it had mana value 3 or less, surveil 2. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)

Dance with Devils

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

Parasitic Grasp

Cleave {1}{B}{B} (You may cast this spell for its cleave cost. If you do, remove the words in square brackets.)
Parasitic Grasp deals 3 damage to target [Human] creature. You gain 3 life.

Black Dragon Gate

This land enters tapped.
As this land enters, choose a color other than black.
{T}: Add {B} or one mana of the chosen color.

Demon's Horn

Whenever a player casts a black spell, you may gain 1 life.

Infernal Pet

Whenever you cast your second spell each turn, put a +1/+1 counter on this creature and it gains flying until end of turn.

Bloodfell Caves

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

Return the Favor

Spree (Choose one or more additional costs.)
+ {1} — Copy target instant spell, sorcery spell, activated ability, or triggered ability. You may choose new targets for the copy.
+ {1} — Change the target of target spell or ability with a single target.

Glistening Goremonger

When this creature dies, each opponent sacrifices an artifact or creature of their choice.

Pyretic Prankster

{3}{B/P}: Transform this creature. Activate only as a sorcery. ({B/P} can be paid with either {B} or 2 life.)

Pyretic Prankster // Glistening Goremonger

Fiery Emancipation

If a source you control would deal damage to a permanent or player, it deals triple that damage to that permanent or player instead.

Bathe in Gold

Create a Treasure token. (Then exile this card. You may cast the creature later from exile.)

Young Red Dragon

Young Red Dragon // Bathe in Gold

Ambush Gigapede

Flash
When this creature enters, target creature an opponent controls gets -2/-2 until end of turn.

Rakdos Signet

Ghastly Death Tyrant

When this creature enters, choose one —
• Disintegration Ray — Destroy target enchantment an opponent controls. You lose life equal to its mana value.
• Death Ray — Creatures you control gain deathtouch until end of turn.

Tibalt, Rakish Instigator

Your opponents can't gain life.
−2: Create a 1/1 red Devil creature token with "When this token dies, it deals 1 damage to any target."

Karlach, Fury of Avernus

Whenever you attack, if it's the first combat phase of the turn, untap all attacking creatures. They gain first strike until end of turn. After this phase, there is an additional combat phase.
Choose a Background (You can have a Background as a second commander.)

Raphael, Fiendish Savior

Flying
Other Demons, Devils, Imps, and Tieflings you control get +1/+1 and have lifelink.
At the beginning of each end step, if a creature card was put into your graveyard from anywhere this turn, create a 1/1 red Devil creature token with "When this token dies, it deals 1 damage to any target."

Witty Roastmaster

Alliance — Whenever another creature you control enters, this creature deals 1 damage to each opponent.

Havoc Festival

Players can't gain life.
At the beginning of each player's upkeep, that player loses half their life, rounded up.

HELIOS One

{T}: Add {C}.
{1}, {T}: You get {E} (an energy counter).
{3}, {T}, Pay X {E}, Sacrifice this land: Destroy target nonland permanent with mana value X. Activate only as a sorcery.

Sweeping Cleave

Target creature you control gains double strike until end of turn. (Then exile this card. You may cast the artifact later from exile.)

Two-Handed Axe

Whenever equipped creature attacks, double its power until end of turn.
Equip {1}{R}

Two-Handed Axe // Sweeping Cleave

Cloudkill

All creatures get -X/-X until end of turn, where X is the greatest mana value of a commander you own on the battlefield or in the command zone.

Reckless Barbarian

Into the Maw of Hell

Destroy target land. Into the Maw of Hell deals 13 damage to target creature.

Armor of Shadows

Until end of turn, target creature gets +1/+0 and gains indestructible. (Damage and effects that say "destroy" don't destroy it.)

Command Beacon

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

Suspicious Bookcase

Defender
{3}, {T}: Target creature can't be blocked this turn.

Rooftop Assassin

Flash
Flying, lifelink
When this creature enters, destroy target creature an opponent controls that was dealt damage this turn.

Explosive Entry

Destroy up to one target artifact. Put a +1/+1 counter on up to one target creature.

Devil

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

Maestros Theater

When this land enters, sacrifice it. When you do, search your library for a basic Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle and you gain 1 life.

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.)

Neutralize the Guards

Creatures target opponent controls get -1/-1 until end of turn. Surveil 2. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)

Run Amok

Target attacking creature gets +3/+3 and gains trample until end of turn.

Desert's Due

Target creature gets -2/-2 until end of turn. It gets an additional -1/-1 until end of turn for each Desert you control.

Light 'Em Up

Casualty 2 (As you cast this spell, you may sacrifice a creature with power 2 or greater. When you do, copy this spell and you may choose a new target for the copy.)
Light 'Em Up deals 2 damage to target creature or planeswalker.

Demon of Wailing Agonies

Flying
Lieutenant — As long as you control your commander, this creature gets +2/+2 and has "Whenever this creature deals combat damage to a player, that player sacrifices a creature of their choice."

Tramway Station

This land enters tapped.
{T}: Add {B} or {R}.
{2}{B}{R}, {T}, Sacrifice this land: Draw a card.

Swamp

Exotic Orchard

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

Sol Ring

Skulduggery

Until end of turn, target creature you control gets +1/+1 and target creature an opponent controls gets -1/-1.

Blasphemous Act

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

Genasi Enforcers

Myriad (Whenever this creature attacks, for each opponent other than defending player, you may create a token copy that's tapped and attacking that player or a planeswalker they control. Exile the tokens at end of combat.)
{1}{R}: Creatures you control named Genasi Enforcers get +1/+0 until end of turn.

Mayhem Devil

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

Quick Draw

Target creature you control gets +1/+1 and gains first strike until end of turn. Creatures target opponent controls lose first strike and double strike until end of turn.

Demonspine Whip

{X}: Equipped creature gets +X/+0 until end of turn.
Equip {1}

Apocalypse Demon

Flying
Apocalypse Demon's power and toughness are each equal to the number of cards in your graveyard.
At the beginning of your upkeep, tap this creature unless you sacrifice another creature.

Mountain

Fire Diamond

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

Charcoal Diamond

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

Entropic Cloud

Creatures you control gain deathtouch until end of turn. (Then exile this card. You may cast the creature later from exile.)

Topaz Dragon

Topaz Dragon // Entropic Cloud

Searstep Pathway

Blightstep Pathway

Blightstep Pathway // Searstep Pathway

Strangle

Strangle deals 3 damage to target creature or planeswalker.

Reliquary Tower

You have no maximum hand size.
{T}: Add {C}.

Bojuka Bog

This land enters tapped.
When this land enters, exile target player's graveyard.
{T}: Add {B}.

Bucolic Ranch

{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a Mount spell.
{3}, {T}: Look at the top card of your library. If it's a Mount card, you may reveal it and put it into your hand. If you don't put it into your hand, you may put it on the bottom of your library.

Treasure

{T}, Sacrifice this token: Add one mana of any color.

Burning-Rune Demon

Flying
When this creature enters, you may search your library for exactly two cards not named Burning-Rune Demon that have different names. If you do, reveal those cards. An opponent chooses one of them. Put the chosen card into your hand and the other into your graveyard, then shuffle.

Auger Spree

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

Thriving Bluff

This land enters tapped. As it enters, choose a color other than red.
{T}: Add {R} or one mana of the chosen color.

Murder

Hellspur Brute

Affinity for outlaws (This spell costs {1} less to cast for each Assassin, Mercenary, Pirate, Rogue, and/or Warlock you control.)
Trample