When you die, there is a chance that the level as you left it is saved, to be reloaded in a later game. Such levels are known as bones levels, bones files or simply bones. There can only be one bones file per dungeon level, and each bones file only has a random chance of being selected as a bones level when entered for the first time. A bones level can, however, have more than one ghost if a second adventurer is killed there.


How to tell if a level is a bones level:

  • Large concentration of different monsters.
  • Wounded monsters (can be identified with a stethoscope).
  • Broken doors (can be identified with the [:] command).
  • Holes in walls.
  • Empty or partially empty throne rooms, zoos, leprechaun halls, or any other special rooms.
  • Engraved messages other than those randomly placed by NetHack.
  • Few to no items lying on the floor.
  • Suspicious or unusual items around the level. For example, disarmed beartraps are rarely, if ever, generated randomly.
  • Piles of items related to specific monsters. A collection of quarterstaffs or suits of leather armor, or even a noticeable number of elven, dwarvish, or orcish items can indicate that some combat has occurred on the level before you arrived.
  • A named ghost, in a room other than a graveyard.
  • Named monsters, which are usually not generated for that particular level (for example, an archon on DL4).
  • Presence of corpses, which are never randomly generated (except for in the Valley of the Dead, which can have bones also).
  • Presence of fruit (slime mold) with a different name than the one you set (this is a dead giveaway).
  • A saddled horse

What to do with bonesEdit

A bones level will contain some remnant of the player whose bones are laying about. Typically this is a ghost bearing the name of the player, usually stationed over the bones pile (ghosts move slowly). If the deceased player was killed by a vampire, the ghost will be replaced with a vampire bearing the name. A similar process happens with mummies, wraiths, and green slimes. If the player was petrified or killed by a footrice, there is a statue of the player instead.

Killing or luring the ghost or vampire away gives the player access to the bones. Bones piles contain the entire inventory of the player, randomly cursed. It's usually a bad idea to quaff, Put on, read, wield, or Wear anything from a bones pile until it has been properly BUC identified, as many objects are likely to be cursed.

Beware! The original killer is still lurking about the level, probably not too far from the site of the bones. If you discover a bones pile with very advanced items, be very careful about running into whatever managed to kill your predecessor!

On the other hand, you want to get at the wands of fire or lightning many players carry before monsters can use them against you. Luckily, the ghost is usually generated asleep on top.

One thing to note here that I could not figure out until some source diving:

Nethack saves the loading of bones for real characters. I created a wizard mode bones with the inventory of my dead character (I should have started in explorer mode), and left it for the new (starting out explorer mode) character. I found that you cannot load bones as an explorer mode character.


Item identificationEdit

Objects that the deceased player has #named will be reset to whatever description that object has in the current player's game. In other words, if the deceased had a yellow potion named "this burns when thrown" (meaning it was acid), but acid in the current player's game is a purple potion, the potion will show up as purple, without a name. The exception to this rule is fruit, which retains its name in bones piles. Engraving "Look out for the master mind flayer!" is a clever dying action to inform the bones finder about your demise.

Assuming that the game is being played on a public server such as NAO, the less scrupulous may approach the deceased player online and ask nicely what key items were being carried. This is metagaming however, and some players may not wish to oblige the bones discoverer.

Item identification via the class of the deceasedEdit

When encountering a bones level, it can be advantageous to know some details of the deceased, or at least his or her class. For example, if you find a grave with a quarterstaff, a randomly named cloak, two spellbooks, and a magic marker, you can be fairly certain the corpse is that of an early wizard, from which you can deduce that the cloak is a cloak of magic resistance. This method comes with no guarantees, but the more "indicator items" you find, the more certain you can be.

Class is indicated by
Archeologist bullwhip, fedora, tinning kit
Barbarian two-handed sword, battle-axe
Caveman large number of rocks and/or flint stones
Healer scalpel, stethoscope
Knight lance, many apples and carrots
Monk many apples and oranges, a robe
Priest 4 potions of water, both of: mace and robe
Ranger two large stacks of arrows
Rogue large stack of daggers, sack, lock pick
Samurai large stack of ya (bamboo arrows), katana and short sword
Tourist Hawaiian shirt, expensive camera, credit card, stack of 4 scrolls
Valkyrie long sword, small shield, dagger
Wizard quarterstaff, randomly named cloak, two spellbooks, many other magical items

Rogues and Valkyries are hard to identify, since they both start with items common to other classes, or commonly generated.

Ineligible bones levelsEdit

These levels cannot leave bones.[1]

Note that 'special' levels may be loaded as bones at a different level than they were saved at, sometimes breaking other ad hoc rules like 'no polymorph traps before DL8'.

If not in an ineligible level, there is an additional 1 in (1+(depth/4)) chance to not leave a bones file. This means that the chance to leave bones at DL 4-7 is 50%, DL 8-11 is 66%, DL 12-14 is 75%, DL 15-17 is 80%, etc. (note that DL 1-3 has a 1 in 1 chance to not leave bones, hence being listed as ineligible)


Whether using the contents of a deceased player's bones is ethical is left to the player to decide. Bones can often make a difficult game much easier by providing items that the current player has not "earned" yet.

Finding one's own bones is an even more difficult position. Luckily on a public server there are enough players that this is unlikely to happen too frequently.

If the deceased player's dumplog is available, it can be used to identify items in the bones pile. Doing so is a form of metagaming that could be considered unethical.

Bones files locations Edit

On the Windows port (at least), the data for a bones file is stored in the playground directory. As the filename contains clues to where the player died, it is trivial to identify potential bones levels. The file is created when a player dies on a bones-capable level and is deleted when a bones level is reached and incorporated in to an active game. If the player later dies on a bones-capable level, the file may be re-created with the appropriate filename.

As such, if the player observes the files within the playground, they can notice when a suitable level is coming up, and notice if the file is deleted, and thus know that they are on a bones level.

The file naming format that is used is "bon<branch><role>.<level>", for example "bonM0.T" is the bones file for Minetown.

Within the filename, <branch> is one of:

And <role>:

And <level> is one of:

  • Numbers 1 through 53 - ordinary levels eligible for leaving bones (this number is offset from the first of the branch appropriate - i.e. if the bones are on the second level of the mines, the filename would be "bonM0.2")
  • O - Oracle (implied that <branch> would be "D" as Oracle can only be in Dungeons of Doom)
  • T - Minetown
  • R - Rogue level
  • Q - Quest
  • V - Valley of the Dead
  • A - Asmodeus' Lair
  • B - Baalzebub Lair
  • J - Juiblex's Swamp
  • O - Orcus Town - (implied that <branch> would be "G" as Orcus Town can only be in Gehennom)
  • X - Wizard's Tower

The file is not designed to be human-readable. The characters corresponding to each level and branch are defined in dungeon.def.

Wizard mode Edit

In Wizard mode, you will be prompted when you reach a bones level with the message "Get bones? [yn] (n)", allowing you to selectively retrieve the bones file for that level.

When you die on a bones-suitable level, you will be presented with the opportunity to "Save bones? [yn] (n)", again allowing you to selectively save bones files. If there was already a bones file for that level (i.e. you said no to getting bones when entering a level) you will also be prompted with "Bones file already exists. Replace? [yn] (n)", allowing you to selectively overwrite the bones file for that level.

The side effect of this is that you may encounter bones files on very low levels with a full ascension kit or practically impossible items (+14 Grayswandir), and if the level is loaded as a bones level later on, can storm through the game with score fully counted. This is definitely cheating if the sole purpose of the Wizard mode game was to create such a setup.


  1. bones.c#line18

See alsoEdit