A dungeon spread is a simpler version of an adventure spread that's optimized for quickly building dungeon-focused adventures. In this variant, you divide The Deck of Many Things card set into three separate decks: a locations deck, a features deck, and an optional story deck. For simplicity, use the literal meanings of the cards in the locations and features decks; these cards are straightforward descriptions of potential locations and of the creatures, treasures, and other features characters might find in these locations.
If you want to create a prelude to the dungeon, use the optional steps that call for the story deck, and give those cards their full range of symbolic meaning as discussed in the "Reading the Cards" section. If you'd rather dive straight into the action, you can skip those steps and omit the story deck.