Barrowin of Clan Undurr

When Barrowin enters, venture into the dungeon. (Enter the first room or advance to the next room.)
Whenever Barrowin attacks, return up to one creature card with mana value 3 or less from your graveyard to the battlefield if you've completed a dungeon.

Glasspool Shore

Glasspool Mimic

You may have this creature enter as a copy of a creature you control, except it's a Shapeshifter Rogue in addition to its other types.

Glasspool Mimic // Glasspool Shore

Tazri, Beacon of Unity

This spell costs {1} less to cast for each creature in your party.
{2/U}{2/B}{2/R}{2/G}: Look at the top six cards of your library. You may reveal up to two Cleric, Rogue, Warrior, Wizard, and/or Ally cards from among them and put them into your hand. Put the rest on the bottom of your library in a random order.

Veteran Adventurer

Veteran Adventurer is also a Cleric, Rogue, Warrior, and Wizard.
This spell costs {1} less to cast for each creature in your party.
Vigilance

Base Camp

This land enters tapped.
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a Cleric, Rogue, Warrior, or Wizard spell or to activate an ability of a Cleric, Rogue, Warrior, or Wizard.

Concerted Defense

Counter target noncreature spell unless its controller pays {1} plus an additional {1} for each creature in your party. (Your party consists of up to one each of Cleric, Rogue, Warrior, and Wizard.)

Midnight Pathlighter

Creatures you control can't be blocked except by legendary creatures.
Whenever one or more creatures you control deal combat damage to a player, venture into the dungeon. (Enter the first room or advance to the next room.)

Solemn Doomguide

Flying
Each creature card in your graveyard that's a Cleric, Rogue, Warrior, and/or Wizard has unearth {1}{B}. ({1}{B}: Return the card to the battlefield. The creature gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)

Dawn Charm

Choose one —
• Prevent all combat damage that would be dealt this turn.
• Regenerate target creature.
• Counter target spell that targets you.

Evolving Wilds

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

Find the Path

Enchant land
When this Aura enters, venture into the dungeon. (Enter the first room or advance to the next room.)
Enchanted land has "{T}: Add {G}{G}."

Spoils of Adventure

This spell costs {1} less to cast for each creature in your party. (Your party consists of up to one each of Cleric, Rogue, Warrior, and Wizard.)
You gain 3 life and draw three cards.

Island

Burakos, Party Leader

Burakos is also a Cleric, Rogue, Warrior, and Wizard.
Whenever Burakos attacks, defending player loses X life and you create X Treasure tokens, where X is the number of creatures in your party.
Choose a Background (You can have a Background as a second commander.)

White Plume Adventurer

When this creature enters, you take the initiative.
At the beginning of each opponent's upkeep, untap a creature you control. If you've completed a dungeon, untap all creatures you control instead.

Thawing Glaciers

This land enters tapped.
{1}, {T}: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle. Return this land to its owner's hand at the beginning of the next cleanup step.

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.

Arcane Signet

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

Yuan-Ti Fang-Blade

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

Plains

Varis, Silverymoon Ranger

Reach, ward {1}
Whenever you cast a creature or planeswalker spell, venture into the dungeon. This ability triggers only once each turn. (To venture into the dungeon, enter the first room or advance to the next room.)
Whenever you complete a dungeon, create a 2/2 green Wolf creature token.

You Find a Cursed Idol

Choose one —
• Smash It — Destroy target artifact.
• Lift the Curse — Destroy target enchantment.
• Steal Its Eyes — Create a Treasure token and venture into the dungeon. (Enter the first room or advance to the next room.)

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.

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}

Sefris of the Hidden Ways

Whenever one or more creature cards are put into your graveyard from anywhere, venture into the dungeon. This ability triggers only once each turn. (To venture into the dungeon, enter the first room or advance to the next room.)
Create Undead — Whenever you complete a dungeon, return target creature card from your graveyard to the battlefield.

Fabled Passage

{T}, Sacrifice this land: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle. Then if you control four or more lands, untap that land.

Coveted Prize

This spell costs {1} less to cast for each creature in your party. (Your party consists of up to one each of Cleric, Rogue, Warrior, and Wizard.)
Search your library for a card, put it into your hand, then shuffle. If you have a full party, you may cast a spell with mana value 4 or less from your hand without paying its mana cost.

Nadaar, Selfless Paladin

Vigilance
Whenever Nadaar enters or attacks, venture into the dungeon. (Enter the first room or advance to the next room.)
Other creatures you control get +1/+1 as long as you've completed a dungeon.

Forest

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.)

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.)

Hero's Downfall

Squad Commander

When this creature enters, create a 1/1 white Kor Warrior creature token for each creature in your party. (Your party consists of up to one each of Cleric, Rogue, Warrior, and Wizard.)
At the beginning of combat on your turn, if you have a full party, creatures you control get +1/+0 and gain indestructible until end of turn.

Ingenious Prodigy

Skulk (This creature can't be blocked by creatures with greater power.)
This creature enters with X +1/+1 counters on it.
At the beginning of your upkeep, if this creature has one or more +1/+1 counters on it, you may remove a +1/+1 counter from it. If you do, draw a card.

Shortcut Seeker

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

Rejuvenating Springs

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

Harper Recruiter

Flying
Whenever this creature attacks, look at the top four cards of your library. You may reveal a Cleric card, a Rogue card, a Warrior card, and/or a Wizard card from among them and put those cards into your hand. Put the rest on the bottom of your library in a random order.

Order of Whiteclay

{1}{W}{W}, {Q}: Return target creature card with mana value 3 or less from your graveyard to the battlefield. ({Q} is the untap symbol.)

Panharmonicon

If an artifact or creature entering causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Delver's Torch

Equipped creature gets +1/+1.
Whenever equipped creature attacks, venture into the dungeon. (Enter the first room or advance to the next room.)
Equip {3} ({3}: Attach to target creature you control. Equip only as a sorcery.)

Ellywick Tumblestrum

+1: Venture into the dungeon. (Enter the first room or advance to the next room.)
−2: Look at the top six cards of your library. You may reveal a creature card from among them and put it into your hand. If it's legendary, you gain 3 life. Put the rest on the bottom of your library in a random order.
−7: You get an emblem with "Creatures you control have trample and haste and get +2/+2 for each differently named dungeon you've completed."

Undermountain Adventurer

Vigilance
When this creature enters, you take the initiative.
{T}: Add {G}{G}. If you've completed a dungeon, add six {G} instead.

Thorough Investigation

Whenever you attack, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.")
Whenever you sacrifice a Clue, venture into the dungeon. (Enter the first room or advance to the next room.)

Triumphant Adventurer

Deathtouch
During your turn, this creature has first strike.
Whenever this creature attacks, venture into the dungeon. (Enter the first room or advance to the next room.)

Deadly Alliance

This spell costs {1} less to cast for each creature in your party. (Your party consists of up to one each of Cleric, Rogue, Warrior, and Wizard.)
Destroy target creature or planeswalker.

Displacer Kitten

Avoidance — Whenever you cast a noncreature spell, exile up to one target nonland permanent you control, then return that card to the battlefield under its owner's control.

Ephemerate

Exile target creature you control, then return it to the battlefield under its owner's control.
Rebound (If you cast this spell from your hand, exile it as it resolves. At the beginning of your next upkeep, you may cast this card from exile without paying its mana cost.)

Nalia de'Arnise

You may look at the top card of your library any time.
You may cast Cleric, Rogue, Warrior, and Wizard spells from the top of your library.
At the beginning of combat on your turn, if you have a full party, put a +1/+1 counter on each creature you control and those creatures gain deathtouch until end of turn.

Intrepid Outlander

Reach
Pack tactics — Whenever this creature attacks, if you attacked with creatures with total power 6 or greater this combat, venture into the dungeon. (Enter the first room or advance to the next room.)

Return to Dust

Exile target artifact or enchantment. If you cast this spell during your main phase, you may exile up to one other target artifact or enchantment.

Bar the Gate

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

Acererak the Archlich

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

Yuan-Ti Malison

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

Spara's Headquarters

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

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.)

Planar Ally

Flying
Whenever this creature attacks, venture into the dungeon. (Enter the first room or advance to the next room.)

Unbreakable Formation

Creatures you control gain indestructible until end of turn.
Addendum — If you cast this spell during your main phase, put a +1/+1 counter on each of those creatures and they gain vigilance until end of turn.

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

Displacer Beast

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

Commander's Sphere

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

Stonework Packbeast

Stonework Packbeast is also a Cleric, Rogue, Warrior, and Wizard.
{2}: Add one mana of any color.

Seasoned Dungeoneer

When this creature enters, you take the initiative.
Whenever you attack, target attacking Cleric, Rogue, Warrior, or Wizard gains protection from creatures until end of turn. It explores. (Reveal the top card of your library. Put that card into your hand if it's a land. Otherwise, put a +1/+1 counter on the creature, then put the card back or put it into your graveyard.)

Bonders' Enclave

{T}: Add {C}.
{3}, {T}: Draw a card. Activate only if you control a creature with power 4 or greater.

Mutavault

{T}: Add {C}.
{1}: This land becomes a 2/2 creature with all creature types until end of turn. It's still a land.

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.)

Linvala, Shield of Sea Gate

Flying
At the beginning of combat on your turn, if you have a full party, choose target nonland permanent an opponent controls. Until your next turn, it can't attack or block, and its activated abilities can't be activated.
Sacrifice Linvala: Choose hexproof or indestructible. Creatures you control gain that ability until end of turn.

Hama Pashar, Ruin Seeker

Room abilities of dungeons you own trigger an additional time.

Practiced Tactics

Choose target attacking or blocking creature. Practiced Tactics deals damage to that creature equal to twice the number of creatures in your party. (Your party consists of up to one each of Cleric, Rogue, Warrior, and Wizard.)

Cloister Gargoyle

When this creature enters, venture into the dungeon. (Enter the first room or advance to the next room.)
As long as you've completed a dungeon, this creature gets +3/+0 and has flying.

Archpriest of Iona

Archpriest of Iona's power is equal to the number of creatures in your party. (Your party consists of up to one each of Cleric, Rogue, Warrior, and Wizard.)
At the beginning of combat on your turn, if you have a full party, target creature gets +1/+1 and gains flying until end of turn.

Raffine's Tower

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

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.)

Dungeon Delver

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

Thwart the Grave

This spell costs {1} less to cast for each creature in your party. (Your party consists of up to one each of Cleric, Rogue, Warrior, and Wizard.)
Return target creature card and up to one target Cleric, Rogue, Warrior, or Wizard creature card from your graveyard to the battlefield.

Swamp

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.)