Acererak the Archlich

When Acererak the Archlich enters, if you haven't completed Tomb of Annihilation, return Acererak the Archlich to its owner's hand and venture into the dungeon.
Whenever Acererak the Archlich attacks, for each opponent, you create a 2/2 black Zombie creature token unless that player sacrifices a creature of their choice.

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice Mind Stone: Draw a card.

Aether Channeler

When Aether Channeler enters, choose one —
• Create a 1/1 white Bird creature token with flying.
• Return another target nonland permanent to its owner's hand.
• Draw a card.

Serum Visions

Victimize

Choose two target creature cards in your graveyard. Sacrifice a creature. If you do, return the chosen cards to the battlefield tapped.

Wash Away

Cleave {1}{U}{U} (You may cast this spell for its cleave cost. If you do, remove the words in square brackets.)
Counter target spell [that wasn't cast from its owner's hand].

Zombie Ogre

At the beginning of your end step, if a creature died this turn, venture into the dungeon. (Enter the first room or advance to the next room.)

Ashnod's Altar

Drowned Catacomb

Drowned Catacomb enters tapped unless you control an Island or a Swamp.
{T}: Add {U} or {B}.

Dungeon Delver

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

Dimir Signet

Carrion Feeder

Carrion Feeder can't block.
Sacrifice a creature: Put a +1/+1 counter on Carrion Feeder.

Sign in Blood

Target player draws two cards and loses 2 life.

Clattering Skeletons

When Clattering Skeletons dies, venture into the dungeon. (Enter the first room or advance to the next room.)

Trailblazer's Torch

When Trailblazer's Torch enters, you take the initiative.
Whenever equipped creature becomes blocked, it deals 2 damage to each creature blocking it.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Countersquall

Counter target noncreature spell. Its controller loses 2 life.

Tomb of Horrors Adventurer

When Tomb of Horrors Adventurer 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.)

Phyrexian Reclamation

{1}{B}, Pay 2 life: Return target creature card from your graveyard to your hand.

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.)

Rogue's Passage

{T}: Add {C}.
{4}, {T}: Target creature can't be blocked this turn.

Read the Bones

Scry 2, then draw two cards. You lose 2 life. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Precipitous Drop

Enchant creature
When Precipitous Drop enters, venture into the dungeon. (Enter the first room or advance to the next room.)
Enchanted creature gets -2/-2. It gets -5/-5 instead as long as you've completed a dungeon.

Vicious Battlerager

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

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice Commander's Sphere: Draw a card.

Yuan-Ti Malison

Yuan-Ti Malison can't be blocked as long as it's attacking alone.
Whenever Yuan-Ti Malison deals combat damage to a player, venture into the dungeon. (Enter the first room or advance to the next room.)

Shortcut Seeker

Whenever Shortcut Seeker deals combat damage to a player, venture into the dungeon. (Enter the first room or advance to the next room.)

Pull from Tomorrow

Bane's Contingency

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

Agent of the Iron Throne

Commander creatures you own have "Whenever an artifact or creature you control is put into a graveyard from the battlefield, each opponent loses 1 life."

Counterspell

Shipwreck Marsh

Shipwreck Marsh enters tapped unless you control two or more other lands.
{T}: Add {U} or {B}.

Burnished Hart

{3}, Sacrifice Burnished Hart: Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Feywild Caretaker

When Feywild Caretaker 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.

Sol Ring

Aarakocra Sneak

Flying
When Aarakocra Sneak enters, you take the initiative.

Preordain

Scry 2, then draw a card. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Swamp

Mystic Sanctuary

({T}: Add {U}.)
Mystic Sanctuary enters tapped unless you control three or more other Islands.
When Mystic Sanctuary enters untapped, you may put target instant or sorcery card from your graveyard on top of your library.

Displacer Beast

When Displacer Beast enters, venture into the dungeon. (Enter the first room or advance to the next room.)
Displacement — {3}{U}: Return Displacer Beast to its owner's hand.

Fates' Reversal

Return up to one target creature card from your graveyard to your hand. Venture into the dungeon. (Enter the first room or advance to the next room.)

Eccentric Apprentice

Flying
When Eccentric Apprentice enters, venture into the dungeon. (Enter the first room or advance to the next room.)
At the beginning of combat on your turn, if you've completed a dungeon, up to one target creature becomes a Bird with base power and toughness 1/1 and flying until end of turn.

Sunken Hollow

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

Island

Fifty Feet of Rope

Climb Over — {T}: Target Wall can't block this turn.
Tie Up — {3}, {T}: Target creature doesn't untap during its controller's next untap step.
Rappel Down — {4}, {T}: Venture into the dungeon. Activate only as a sorcery. (Enter the first room or advance to the next room.)

No Rest for the Wicked

Sacrifice No Rest for the Wicked: Return to your hand all creature cards in your graveyard that were put there from the battlefield this turn.

Access Tunnel

{T}: Add {C}.
{3}, {T}: Target creature with power 3 or less can't be blocked this turn.

Dungeoneer's Pack

Dungeoneer's Pack enters tapped.
{2}, {T}, Sacrifice Dungeoneer's Pack: You take the initiative, gain 3 life, draw a card, and create a Treasure token. Activate only as a sorcery. (A Treasure token is an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Bar the Gate

Counter target creature or planeswalker spell. Venture into the dungeon. (Enter the first room or advance to the next room.)

Beacon of Unrest

Put target artifact or creature card from a graveyard onto the battlefield under your control. Shuffle Beacon of Unrest into its owner's library.

Baleful Strix

Flying, deathtouch
When Baleful Strix enters, draw a card.

Ponder

Look at the top three cards of your library, then put them back in any order. You may shuffle.
Draw a card.

Dungeon Map

{T}: Add {C}.
{3}, {T}: Venture into the dungeon. Activate only as a sorcery. (Enter the first room or advance to the next room.)

Hinder

Counter target spell. If that spell is countered this way, put that card on your choice of the top or bottom of its owner's library instead of into that player's graveyard.

Evolving Wilds

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

Reassembling Skeleton

{1}{B}: Return Reassembling Skeleton from your graveyard to the battlefield tapped.

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.)

Persistent Specimen

{2}{B}: Return Persistent Specimen from your graveyard to the battlefield tapped.

Altar of Dementia

Sacrifice a creature: Target player mills cards equal to the sacrificed creature's power.

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.

Command Tower

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

Underdark Explorer

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

Secret Door

Defender
{4}{U}: Venture into the dungeon. Activate only as a sorcery. (Enter the first room or advance to the next room.)

Arcane Signet

Passageway Seer

Lifelink
When Passageway Seer enters, you take the initiative.
At the beginning of your end step, if you have the initiative, put a +1/+1 counter on Passageway Seer.

Solemn Simulacrum

When Solemn Simulacrum enters, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
When Solemn Simulacrum dies, you may draw a card.

Sarevok's Tome

When Sarevok's Tome enters, you take the initiative.
{T}: Add {C}. If you have the initiative, add {C}{C} instead.
{3}, {T}: Exile cards from the top of your library until you exile a nonland card. You may cast that card without paying its mana cost. Activate only if you've completed a dungeon.

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 artifact: Add one mana of any color.")

Yuan-Ti Fang-Blade

Deathtouch
Whenever Yuan-Ti Fang-Blade deals combat damage to a player, venture into the dungeon. (Enter the first room or advance to the next room.)

Viscera Seer

Sacrifice a creature: Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

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.)

Maestros Theater

When Maestros Theater 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.

Night's Whisper

Terramorphic Expanse

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

Rilsa Rael, Kingpin

Deathtouch
When Rilsa Rael, Kingpin 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.

Ravenloft Adventurer

When Ravenloft Adventurer enters, you take the initiative.
If a creature an opponent controls would die, instead exile it and put a hit counter on it.
Whenever Ravenloft Adventurer 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.

Unearth

Return target creature card with mana value 3 or less from your graveyard to the battlefield.
Cycling {2} ({2}, Discard this card: Draw a card.)

Dread Return

Return target creature card from your graveyard to the battlefield.
Flashback—Sacrifice three creatures. (You may cast this card from your graveyard for its flashback cost. Then exile it.)