Early versions of NetHack, such as NetHack 3.0.0, kept track of which items are artifacts through their names, allowing a flexible artifact set (i.e., multiple artifacts can be of the same item type) without needing separate fields in the object structure to track artifact status. As a consequence of this mechanic, the game needed to prevent non-artifacts being turned into artifacts via naming them (e.g. naming a long sword "Excalibur" to turn it into Excalibur). So if you tried to name a non-artifact with the name of an artifact of the same base type, the game would prevent you and you will mis-engrave. ("Your hand slips...")
In later versions of NetHack, items used a separate "artifact flag" to identify whether they were artifacts (and which artifact they were), meaning that this mechanic was no longer necessary to prevent inadvertent creation of artifacts, but it remained in the codebase. This made it possible to identify items; for example, naming a helmet "The Mitre of Holiness" would fail if and only if the helmet is a helm of brilliance.
By this exploit, you could identify (or rule out) the following items:
|Appearance||Item type||Artifact name|
|amulet||amulet of ESP||The Eye of the Aethiopica|
|gray stone||luckstone||The Heart of Ahriman|
|magic helm*||helm of brilliance||The Mitre of Holiness|
Although this exploit never appeared on the official bug list, it was fixed in NetHack 3.6.0; naming any item in the the appropriate category, if you haven't identified its type, with the appropriate name, will mis-engrave whether or not the item's type is the artifact's base. Thus, attempting to name an unidentified gray stone "The Heart of Ahriman" will fail, regardless of whether it's a luckstone or touchstone, but if you've formally identified it as a touchstone you can name it successfully (and ineffectively).
The original fix in 3.6.0 still allowed a slightly different exploit with the same results, relying on the fact that formatting (capitalization and article placement) is corrected only for the actual type -- if naming the item in all lowercase, the exploit still works. Similarly, if using the correct capitalization but dropping the article (e.g. naming a gray stone "Heart of Ahriman" instead of "The Heart of Ahriman"), the missing article will be inserted only if the type matches the artifact.
The following information pertains to an upcoming version (3.7.0). If this version is now released, please verify that it is still accurate, then update the page to incorporate this information.The artifact-naming trick is fully patched as of commit d886b43.
NetHack 3.0.0 lacked an artifact marker on items, but instead checked the name and object base type of an item to determine whether it is an artifact; this allowed naming Sting or Orcrist to work, but the game had to forbid naming attempts that would create other artifacts. In the code:
- NetHack_3.0.0/do_name.c#line157 which causes your hand to slip if you try – although with a different message.
- See NetHack_3.0.0/weapon.c#line58 for a call from the weapons code to the spec_abon function that determines the to-hit bonus of an artifact, or line143 or NetHack_3.0.0/mhitu.c#line674 for other similar calls.
- NetHack_3.0.0/artifact.c#line237 contains the definition of spec_abon, which calls the function get_artifact to determine whether an item is an artifact.
- get_artifact in line109 compares the base type and name of the item to those in the artifact tables above.
Many variants adopt the aforementioned fixes for the artifact-naming trick, with some exceptions.
In SLASH'EM, the artifact naming trick remains unpatched, and is even more effective due to the many new artifacts.
In GruntHack, items can now bear the same name as an artifact, removing the ability to determine object identities this way.
- Trivially identifiable in SLASH'EM with the showweight option enabled.
- Trivially identifiable by having a light radius of 3, vs. 2 for normal candles.
- Easily identified by applying it.