Elder Brain

Menace
Whenever this creature attacks a player, exile all cards from that player's hand, then they draw that many cards. You may play lands and cast spells from among the exiled cards for as long as they remain exiled. If you cast a spell this way, you may spend mana as though it were mana of any color to cast it.

Ravenloft Adventurer

When this creature enters, you take the initiative.
If a creature an opponent controls would die, instead exile it and put a hit counter on it.
Whenever this creature attacks, if you've completed a dungeon, defending player loses 1 life for each card they own in exile with a hit counter on it.

Disfigure

Target creature gets -2/-2 until end of turn.

Vicious Battlerager

When this creature enters, you take the initiative.
Spiked Retribution — Whenever this creature becomes blocked by a creature, that creature's controller loses 5 life.

Swamp

Morphic Pool

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

Feywild Caretaker

When this creature enters, you take the initiative.
At the beginning of your end step, if you have the initiative, create a 1/1 blue Faerie Dragon creature token with flying.

Darkwater Catacombs

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.

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.

Bane's Contingency

Counter target spell. If that spell targets a commander you control, instead counter that spell, scry 2, then draw a card.

Guildpact Informant

Flying
Whenever this creature deals combat damage to a player or planeswalker, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Murder

Stunning Strike

Flash
Enchant creature
When this Aura enters, tap enchanted creature and remove it from combat.
As long as enchanted creature isn't legendary, it doesn't untap during its controller's untap step.

Island

Vengeful Warchief

Whenever you lose life for the first time each turn, put a +1/+1 counter on this creature. (Damage causes loss of life.)

Dungeon Delver

Commander creatures you own have "Room abilities of dungeons you own trigger an additional time."

Spread the Sickness

Destroy target creature, then proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Undercity's Embrace

Target opponent sacrifices a creature of their choice. If you control a creature with power 4 or greater, you gain 4 life.

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

Decanter of Endless Water

You have no maximum hand size.
{T}: Add one mana of any color.

Imoen, Mystic Trickster

Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)
At the beginning of your end step, if you have the initiative, draw a card. Draw another card if you've completed a dungeon.
Choose a Background (You can have a Background as a second commander.)

Ob Nixilis's Cruelty

Target creature gets -5/-5 until end of turn. If that creature would die this turn, exile it instead.

Dream Fracture

Counter target spell. Its controller draws a card.
Draw a card.

Tomebound Lich

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
Lifelink (Damage dealt by this creature also causes you to gain that much life.)
Whenever this creature enters or deals combat damage to a player, draw a card, then discard a card.

Negate

Experimental Augury

Look at the top three cards of your library. Put one of them into your hand and the rest on the bottom of your library in any order. Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Rilsa Rael, Kingpin

Deathtouch
When Rilsa Rael enters, you take the initiative.
Whenever you attack, target attacking creature gains deathtouch until end of turn. If you've completed a dungeon, that creature also gets +5/+0 and gains first strike and menace until end of turn.

Underdark Explorer

Menace (This creature can't be blocked except by two or more creatures.)
When this creature enters, you take the initiative.

Alora, Merry Thief

Whenever you attack, up to one target attacking creature can't be blocked this turn. Return that creature to its owner's hand at the beginning of the next end step.
Choose a Background (You can have a Background as a second commander.)

River of Tears

{T}: Add {U}. If you played a land this turn, add {B} instead.

Myrkul's Edict

Roll a d20.
1—9 | Choose an opponent. That player sacrifices a creature of their choice.
10—19 | Each opponent sacrifices a creature of their choice.
20 | Each opponent sacrifices a creature with the greatest power among creatures that player controls.

Tomb of Horrors Adventurer

When this creature enters, you take the initiative.
Whenever you cast your second spell each turn, copy it. If you've completed a dungeon, copy that spell twice instead. You may choose new targets for the copies. (A copy of a permanent spell becomes a token.)

Slice from the Shadows

This spell can't be countered. (This includes by the ward ability.)
Target creature gets -X/-X until end of turn.

Scurrilous Sentry

Menace
Whenever this creature enters or attacks, it connives. (Draw a card, then discard a card. If you discarded a nonland card, put a +1/+1 counter on this creature.)

Dismal Backwater

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

Shadowheart, Dark Justiciar

{1}{B}, {T}, Sacrifice another creature: Draw X cards, where X is that creature's power.
Choose a Background (You can have a Background as a second commander.)

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.)

Aetherize

Return all attacking creatures to their owner's hand.

Criminal Past

Commander creatures you own have menace and "This creature gets +X/+0, where X is the number of creature cards in your graveyard." (A creature with menace can't be blocked except by two or more creatures.)

Arms of Hadar

Creatures target player controls get -2/-2 until end of turn.

Bake into a Pie

Destroy target creature. Create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this token: You gain 3 life.")

Tasha, the Witch Queen

Whenever you cast a spell you don't own, create a 3/3 black Demon creature token.
+1: Draw a card. For each opponent, exile up to one target instant or sorcery card from that player's graveyard and put a page counter on it.
−3: You may cast a spell from among cards in exile with page counters on them without paying its mana cost.
Tasha, the Witch Queen can be your commander.

Anticipate

Look at the top three cards of your library. Put one of them into your hand and the rest on the bottom of your library in any order.

Arcane Epiphany

This spell costs {1} less to cast if you control a Wizard.
Draw three cards.

Jon Irenicus, Shattered One

At the beginning of your end step, target opponent gains control of up to one target creature you control. Put two +1/+1 counters on it and tap it. It's goaded for the rest of the game and it gains "This creature can't be sacrificed." (It attacks each combat if able and attacks a player other than you if able.)
Whenever a creature you own but don't control attacks, you draw a card.

Viconia, Drow Apostate

At the beginning of your upkeep, if there are four or more creature cards in your graveyard, return a creature card at random from your graveyard to your hand.
Choose a Background (You can have a Background as a second commander.)

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.

Unsummon

Return target creature to its owner's hand.

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.

Kiora's Dambreaker

When this creature enters, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

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."

Contentious Plan

Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)
Draw a card.

Tymora's Invoker

Sage's Row Denizen

Whenever another blue creature you control enters, target player mills two cards.

Bonecaller Cleric

{3}{B}, Sacrifice this creature: Return target creature card from your graveyard to the battlefield. Activate only as a sorcery.

Sorin's Thirst

Sorin's Thirst deals 2 damage to target creature and you gain 2 life.

Wither and Bloom

Target creature gets -3/-3 until end of turn.
{1}{B}, Exile this card from your graveyard: Put a +1/+1 counter on target creature you control. Activate only as a sorcery.

Mari, the Killing Quill

Whenever a creature an opponent controls dies, exile it with a hit counter on it.
Assassins, Mercenaries, and Rogues you control have deathtouch and "Whenever this creature deals combat damage to a player, you may remove a hit counter from a card that player owns in exile. If you do, draw a card and create two Treasure tokens."

Fuel for the Cause

Counter target spell, then proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Safana, Calimport Cutthroat

Menace
At the beginning of your end step, if you have the initiative, create a Treasure token. Create three of those tokens instead if you've completed a dungeon.
Choose a Background (You can have a Background as a second commander.)

Multiclass Baldric

Equipped creature has lifelink if you control a Cleric, deathtouch if you control a Rogue, haste if you control a Warrior, and flying if you control a Wizard.
As long as you have a full party, prevent all damage that would be dealt to equipped creature.
Equip {2}

Cry of the Carnarium

All creatures get -2/-2 until end of turn. Exile all creature cards in all graveyards that were put there from the battlefield this turn. If a creature would die this turn, exile it instead.

Befuddle

Target creature gets -4/-0 until end of turn.
Draw a card.

Lash of the Balrog

As an additional cost to cast this spell, sacrifice a creature or pay {4}.
Destroy target creature.

Modify Memory

Exchange control of two target creatures controlled by different players. If you control neither creature, draw three cards.

Deadly Dispute

As an additional cost to cast this spell, sacrifice an artifact or creature.
Draw two cards and create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Agonizing Syphon

Agonizing Syphon deals 3 damage to any target and you gain 3 life.

Summon Undead

You may mill three cards. Then return a creature card from your graveyard to the battlefield. (To mill a card, put the top card of your library into your graveyard.)

Thriving Isle

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

Command Tower

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

Vraska's Finisher

When this creature enters, destroy target creature or planeswalker an opponent controls that was dealt damage this turn.

Enchant creature
Enchanted creature has flying and "Whenever this creature deals combat damage to a player, venture into the dungeon." (Enter the first room or advance to the next room.)

Dimir Locket

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

Gale's Redirection

Exile target spell, then roll a d20 and add that spell's mana value.
1—14 | You may cast the exiled card for as long as it remains exiled, and you may spend mana as though it were mana of any color to cast that spell.
15+ | You may cast the exiled card without paying its mana cost for as long as it remains exiled.