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.

Flying When this creature enters, 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.)

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.

When this creature enters, 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 Snake Wizard with no mana cost. Eternalize only as a sorcery.)

Room abilities of dungeons you own trigger an additional time.

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 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.

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

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.

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.)

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.

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

As this enchantment enters, choose Khans or Dragons. • Khans — At the beginning of your draw step, draw an additional card, then discard a card. • Dragons — Spells your opponents cast that target you or a permanent you control cost {2} more to cast.

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.)