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

As long as you've completed a dungeon, Gloom Stalker has double strike.

Whenever a creature you control becomes blocked, you may return it to its owner's hand. Whenever one or more creatures you control deal combat damage to a player, draw a card.

Flash Vigilance When Guardian of Faith enters the battlefield, any number of other target creatures you control phase out. (Treat them and anything attached to them as though they don't exist until their controller's next turn.)

Room abilities of dungeons you own trigger an additional time.

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.

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.)

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.)

When White Plume Adventurer enters the battlefield, 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.

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.)

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.

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

Arcane Sanctum enters the battlefield tapped. {T}: Add {W}, {U}, or {B}.

Base Camp enters the battlefield 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.

Dismal Backwater enters the battlefield tapped. When Dismal Backwater enters the battlefield, you gain 1 life. {T}: Add {U} or {B}.

({T}: Add {U}.)

({T}: Add {W}.)

Scoured Barrens enters the battlefield tapped. When Scoured Barrens enters the battlefield, you gain 1 life. {T}: Add {W} or {B}.

({T}: Add {B}.)