The dungeon has 99 floors in total. Although the player can decide to leave the dungeon with an item, or be forced to leave when K.O.'d by a monster.
The main goal is to find the Box of Happiness and return to the dungeon entrance safely with it. The Box of Happiness appears on floor 27 at the earliest and appears on later floors from that point on. While the item is in the inventory, it's no longer possible to use the Outside Scroll (the game says that the Box of Happiness blocked its use), and the stairs go backward, leading to the previous floor. Triggering a Pitfall Trap still sends to the next floor, however.
The secondary goal of the dungeon is to obtain Gold and items to sell at the Shop, expanding the Shop area in the process. On floor 10 of the dungeon, the item Safe always appears. Having it in the inventory prevents losing half of the Gold when defeated during the Adventure.
An additional, third goal is reaching floor 99 and obtaining the Ultimate Scroll.
Depending on how much the store has been expanded, a small amount of carry-in items are allowed (up to 4 maximum).