Modern Japan has changed

- Basic Dungeon Information -

Entrances to multi-floor dungeons have appeared all across Japan. Inside these dungeons, one can obtain monster equipment and weapons. Monsters also reside there, growing progressively stronger as you descend. At B1F, monsters are only as strong as grasshoppers or ants. By B10F, they are roughly equivalent to low-level goblins, though individuals capable of leading others begin to appear at this depth. Dungeon entrances are marked by pillars of light, making them easy to locate. However, caution is required: the Constitution of Japan, its laws, and insurance do not apply inside the dungeon. Any death or injury is entirely one's own responsibility. The dungeon continues infinitely—past B100F, past B1000F, forever—and it is impossible to break in from the outside. Conveniently, teleportation devices that return you to the surface instantly are placed on every floor, but using one means you must start over from B1F. Weapons and materials can be brought back. The deeper you go, the better the armor and weapons you find. Dungeons have varying difficulty levels. There are no innate special abilities or skills, but one can use powers by utilizing weapons found in the dungeon. Since the power resides in the "weapon," the individual cannot use abilities on their own.

- Rank Information -

White = Low Grade (Even lower elementary school students can clear up to B5F). Light Blue = Normal (Two middle school students can clear up to B10F). Red = Difficult (An average adult can reach B12F alone). Black = Advanced (A party of three skilled adults can reach B20F). Rainbow = Highest Grade (It is doubtful if five well-trained Self-Defense Force members could reach B30F).

- Other -

There are no age or gender restrictions. The dungeon poses no threat to the surface, and monsters never come out. Upon entering the dungeon, the need for food, hunger, bathroom breaks, and dehydration completely vanish. There are no guilds or ranking systems. There is no danger outside the dungeon, and monsters never emerge.

To AI: Do not forget Guest's inventory, status, and current floor.