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

Flying Whenever All-Seeing Arbiter enters the battlefield or attacks, draw two cards, then discard a card. Whenever you discard a card, target creature an opponent controls gets -X/-0 until your next turn, where X is the number of different mana values among cards in your graveyard.

Flying When Angel of the Ruins enters the battlefield, exile up to two target artifacts and/or enchantments. Plainscycling {2} ({2}, Discard this card: Search your library for a Plains card, reveal it, put it into your hand, then shuffle.)

Flying When Ashen Rider enters the battlefield or dies, exile target permanent.

Flash Polymorphine — You may have Callidus Assassin enter the battlefield tapped as a copy of any creature on the battlefield, except it has "When this creature enters the battlefield, destroy up to one other target creature with the same name as this creature."

Flying Whenever you cycle or discard another card, scry 1. Cycling {U} ({U}, Discard this card: Draw a card.)

Flying, trample Pay 2 life: 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.)

Flying, lifelink Whenever you draw a card, Dream Trawler gets +1/+0 until end of turn. Whenever Dream Trawler attacks, draw a card. Discard a card: Dream Trawler gains hexproof until end of turn. Tap it.

As an additional cost to cast this spell, sacrifice a creature, discard a card, or pay 4 life. When Dusk Mangler enters the battlefield, each opponent sacrifices a creature, discards a card, and loses 4 life.

Flying, protection from black Echo {3}{W}{W} (At the beginning of your upkeep, if this came under your control since the beginning of your last upkeep, sacrifice it unless you pay its echo cost.) When Karmic Guide enters the battlefield, return target creature card from your graveyard to the battlefield.

When Meteor Golem enters the battlefield, destroy target nonland permanent an opponent controls.

Ward {3} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {3}.) Channel — {2}{U}, Discard Mirrorshell Crab: Counter target spell or ability unless its controller pays {3}.

When Monstrosity of the Lake enters the battlefield, you may pay {5}. If you do, tap all creatures your opponents control, then put a stun counter on each of those creatures. (If a permanent with a stun counter would become untapped, remove one from it instead.) Islandcycling {2} ({2}, Discard this card: Search your library for an Island card, reveal it, put it into your hand, then shuffle.)

Medicus Ministorum — When Sister Hospitaller enters the battlefield, return target creature card from your graveyard to the battlefield. You gain life equal to its mana value.

Vigilance Whenever Sun Titan enters the battlefield or attacks, you may return target permanent card with mana value 3 or less from your graveyard to the battlefield.

Flying Plainscycling {2} ({2}, Discard this card: Search your library for a Plains card, reveal it, put it into your hand, then shuffle.) Eternalize {2}{W}{W} ({2}{W}{W}, Exile this card from your graveyard: Create a token that's a copy of it, except it's a 4/4 black Zombie Dragon with no mana cost. Eternalize only as a sorcery.)

Deathtouch When Rilsa Rael, Kingpin enters the battlefield, 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 Sanctum enters the battlefield tapped. {T}: Add {W}, {U}, or {B}.

As Choked Estuary enters the battlefield, you may reveal an Island or Swamp card from your hand. If you don't, Choked Estuary enters the battlefield tapped. {T}: Add {U} or {B}.

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

{1}, {T}: Add {U}{B}.

{T}, Sacrifice Escape Tunnel: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle. {T}, Sacrifice Escape Tunnel: Target creature with power 2 or less can't be blocked this turn.

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

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

({T}: Add {U} or {B}.) Fetid Pools enters the battlefield tapped. Cycling {2} ({2}, Discard this card: Draw a card.)

({T}: Add {W} or {U}.) Irrigated Farmland enters the battlefield tapped. Cycling {2} ({2}, Discard this card: Draw a card.)

({T}: Add {U}.)

Path of Ancestry enters the battlefield 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.)

({T}: Add {W}.)

Port of Karfell enters the battlefield tapped. {T}: Add {U}. {3}{U}{B}{B}, {T}, Sacrifice Port of Karfell: Mill four cards, then return a creature card from your graveyard to the battlefield tapped. (To mill a card, put the top card of your library into your graveyard.)

As Port Town enters the battlefield, you may reveal a Plains or Island card from your hand. If you don't, Port Town enters the battlefield tapped. {T}: Add {W} or {U}.

({T}: Add {W} or {U}.) Prairie Stream enters the battlefield tapped unless you control two or more basic lands.

As Shineshadow Snarl enters the battlefield, you may reveal a Plains or Swamp card from your hand. If you don't, Shineshadow Snarl enters the battlefield tapped. {T}: Add {W} or {B}.

{1}, {T}: Add {W}{U}.

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

({T}: Add {B}.)

Temple of Deceit enters the battlefield tapped. When Temple of Deceit enters the battlefield, scry 1. {T}: Add {U} or {B}.

Temple of Enlightenment enters the battlefield tapped. When Temple of Enlightenment enters the battlefield, scry 1. {T}: Add {W} or {U}.

Temple of Silence enters the battlefield tapped. When Temple of Silence enters the battlefield, scry 1. {T}: Add {W} or {B}.

When Champion of Wits enters the battlefield, you may draw cards equal to its power. If you do, discard two cards. Eternalize {5}{U}{U} ({5}{U}{U}, Exile this card from your graveyard: Create a token that's a copy of it, except it's a 4/4 black Zombie Naga Wizard with no mana cost. Eternalize only as a sorcery.)

Draw two cards, then discard a card. You gain life equal to the number of cards you've discarded this turn. Jump-start (You may cast this card from your graveyard by discarding a card in addition to paying its other costs. Then exile this card.)

Whenever Ghostly Pilferer becomes untapped, you may pay {2}. If you do, draw a card. Whenever an opponent casts a spell from anywhere other than their hand, draw a card. Discard a card: Ghostly Pilferer can't be blocked this turn.

Whenever you attack, target attacking creature can't be blocked this turn. It connives. Then choose another attacking creature with lesser power. That creature gains double strike until end of turn. (To have a creature connive, draw a card, then discard a card. If you discarded a nonland card, put a +1/+1 counter on that creature.)

{T}, Discard a card: Up to one target creature can't be blocked this turn. Whenever Key to the City becomes untapped, you may pay {2}. If you do, draw a card.

Shadow (This creature can block or be blocked by only creatures with shadow.) Whenever Looter il-Kor deals damage to an opponent, draw a card, then discard a card.

{T}: Draw a card, then discard a card.

Flying When Mulldrifter enters the battlefield, draw two cards. Evoke {2}{U} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters the battlefield.)

{T}: Draw a card, then discard a card. {2}{U}{B}, {T}, Sacrifice Obsessive Stitcher: Return target creature card from your graveyard to the battlefield.

{T}, Discard a creature card: Draw a card.

{T}: Draw a card, then discard a card.

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 Tomebound Lich enters the battlefield or deals combat damage to a player, draw a card, then discard a card.

Deathtouch When Vile Entomber enters the battlefield, search your library for a card, put that card into your graveyard, then shuffle.

When Barrowin of Clan Undurr enters the battlefield, venture into the dungeon. (Enter the first room or advance to the next room.) Whenever Barrowin of Clan Undurr 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.

When Displacer Beast enters the battlefield, 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.

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

Toxic 1 (Players dealt combat damage by this creature also get a poison counter.) {T}, Pay 2 life: Add one mana of any color.

{B}, {T}, Sacrifice Doomed Necromancer: Return target creature card from your graveyard to the battlefield.

{T}, Pay 3 life, Sacrifice Priest of Fell Rites: Return target creature card from your graveyard to the battlefield. Activate only as a sorcery. Unearth {3}{W}{B} ({3}{W}{B}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)

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

As an additional cost to cast this spell, sacrifice a creature or discard a card. Destroy target creature or planeswalker.

Vigilance {T}, Sacrifice Bounty Agent: Destroy target legendary permanent that's an artifact, creature, or enchantment.

Exile target permanent with mana value 4 or greater.

Destroy all creatures, then return a creature card put into a graveyard this way to the battlefield under your control. It's a black Zombie in addition to its other colors and types. Exile Necromantic Selection.

Counter target noncreature spell.

Flash Lifelink When Obscura Interceptor enters the battlefield, it connives. When it connives this way, return up to one target spell to its owner's hand. (To have a creature connive, draw a card, then discard a card. If you discarded a nonland card, put a +1/+1 counter on that creature.)

Enchant creature When Precipitous Drop enters the battlefield, 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.

When Ravenous Chupacabra enters the battlefield, destroy target creature an opponent controls.

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.) When Shriekmaw enters the battlefield, destroy target nonartifact, nonblack creature. Evoke {1}{B} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters the battlefield.)

Flying Sacrifice Spiketail Drakeling: Counter target spell unless its controller pays {2}.

Each player chooses a party from among creatures they control, then sacrifices the rest. (To choose a party, choose up to one each of Cleric, Rogue, Warrior, and Wizard.)

Flying When Sunblast Angel enters the battlefield, destroy all tapped creatures.

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.)

Vigilance Whenever Nadaar, Selfless Paladin enters the battlefield 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.

Flying, lifelink Whenever Radiant Solar or another nontoken creature enters the battlefield under your control, venture into the dungeon. (Enter the first room or advance to the next room.) {W}, Discard Radiant Solar: Venture into the dungeon and you gain 3 life.

Deathtouch As long as it's your turn, Triumphant Adventurer has first strike. Whenever Triumphant Adventurer attacks, venture into the dungeon. (Enter the first room or advance to the next room.)

Flying When Angel of Despair enters the battlefield, destroy target permanent.

Choose two — • Destroy all artifacts. • Destroy all enchantments. • Destroy all creatures with mana value 3 or less. • Destroy all creatures with mana value 4 or greater.

Counter target spell. Draw a card, then discard a card.

You gain 2 life, draw two cards, then discard two cards. Flashback {1}{W}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Sacrifice Felidar Cub: Destroy target enchantment.

When Feywild Caretaker enters the battlefield, 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.

Put target creature card from a graveyard onto the battlefield under your control with a corpse counter on it. If that creature would leave the battlefield, exile it instead of putting it anywhere else. You take the initiative. Escape—{3}{B}{B}, Exile five other cards from your graveyard. (You may cast this card from your graveyard for its escape cost.)

Destroy target permanent. Its controller creates a 3/3 green Elephant creature token.

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.) Destroy target creature or planeswalker. Each creature that convoked Lethal Scheme connives. (Draw a card, then discard a card. If you discarded a nonland card, put a +1/+1 counter on that creature.)

Flying {T}: Draw a card, then discard a card. {X}: Likeness Looter becomes a copy of target creature card in your graveyard with mana value X, except it has flying and this ability. Activate only as a sorcery.

Flash Flying Whenever Malcolm, Alluring Scoundrel deals combat damage to a player, put a chorus counter on it. Draw a card, then discard a card. If there are four or more chorus counters on Malcolm, you may cast the discarded card without paying its mana cost.

Flash Synaptic Disintegrator — When Necron Deathmark enters the battlefield, destroy up to one target creature and target player mills three cards.

When Ravenloft Adventurer enters the battlefield, 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.

Sacrifice Ronom Unicorn: Destroy target enchantment.

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.) At the beginning of your upkeep, return target creature card from your graveyard to the battlefield. At the beginning of each opponent's upkeep, that player sacrifices a creature.

When Solemn Simulacrum enters the battlefield, 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.