# Identification
Identification is considered by some to be the heart of NetHack. Most items in the game start unidentified and are described only by their appearance. There are many methods of identifying them.

Contents

1 Mechanics of identification

1.1 Type identification

1.1.1 Formal type identification
1.1.2 Informal type identification with a prompt
1.1.3 Informal type identification with no prompt

1.2 Individual object identification

2 Straightforward identification

2.1 Initial knowledge
2.2 Scroll of identify
2.3 Spell of identify
2.4 Sitting on a throne
2.5 Touchstone
2.6 Selling in shops

3 Indirect identification

3.1 Price identification
3.2 Weight identification
3.3 Behavior identification

3.3.1 Passive  identification
3.3.2 Identification by using
3.3.3 Identification by monster use
3.3.4 Wand engrave identification
3.3.5 Dropping a ring into a sink

3.4 Monster inventory identification
3.5 Cheat

4 See also
5 External links

Mechanics of identification
Type identification
NetHack gives three 'levels' of type identification:

Formal type identification
Also known as auto-identification', formal identification causes a type of item to be called by its proper name, overriding its appearance and anything you may have called the type.

Informal type identification with a prompt
In some cases, you will be prompted to say what you want to call an type of item that has just been used, either by you or a monster. This can occur, for example, if you are hit by a potion thrown by a monster in circumstances that will not auto-identify it. Potions used by monsters giving unusual effects will also do this, such as a cursed potion of gain level. Dropping rings down sinks sometimes yields such a prompt too.  If the type is already called by a name, you are not asked for a new name; if it was used up, you can #name the item from the discoveries list.

Informal type identification with no prompt
In some cases, the effect of an action will unambiguously identify it to a fully spoiled player, even though NetHack declines to auto-identify it. This happens in most cases when engraving with wands, and when an item's price uniquely identifies it. In these cases, and any ambiguous cases that reduce the possibilities, you will have to use #name to call the type an appropriate name.
Sometimes, a certain action will use up an item in one case, and retain it in another. In these cases, you should call the item by the name of the item that would disappear, then rename it afterwards if it is still available. A common situation for this is throwing gems to unicorns; the unicorn will "gratefully" accept valuable gems, "graciously" accept glass which is not #named, and be "not interested in your junk" and drop #named glass. #naming the gem to distinguish one or the other first means you will know when you next find one.  If you have a single gem of a type, you can #name it "good red", throw it, and if the unicorn refuses the gem, rename it to "red glass".  Various cases of #dipping items into potions fall into this category too.

Individual object identification
Each individual object has properties that can be identified: BUC for everything except gold pieces, erodeproofness for weapons and armor, and enchantment or charges for weapons, armor, wands, and some rings and tools.
Stackable objects with the exact same BUC/erodeproofness/enchantment status will not stack if their identification statuses are different.  For example, if you split a stack of unidentified items, and then formally identify any property of one of split stacks (through any means, whether it is a scroll of identify, or dropping one stack on an altar to formally BUC it), the other stack will not have this object-specific identification "transfer" to it if you attempt to re-merge the stack, although both stacks will still be type-identified.  In order to ensure that stacks merge, you must make sure that their identification statuses are also identical.

Straightforward identification
None of these methods are based on the item's behavior, all are universal, and all result in formal identification by the game engine (don't require naming).

Initial knowledge
Items that you start with are automatically identified for you. This is particularly useful for wizards, who will have 2 spellbooks, 3 scrolls, 2 rings and 1 wand identified from the beginning. In addition, depending on your role you may have some knowledge in weapons and armors. Also, if you start with an oil lamp, the potion of oil will be identified for you.

Scroll of identify
When reading a scroll of identify, you will be allowed to ID one or more of your possessions depending on the scroll's beatitude. The odds are:

Beatitude
1 item
2 items
3 items
4 items
everything

Blessed
1⁄5*
1⁄5
1⁄5
1⁄5
1⁄5

Uncursed
21⁄25
1⁄25
1⁄25
1⁄25
1⁄25

Cursed
always
never
never
never
never

* If your Luck is positive, you will identify two items instead of one.

Spell of identify
Main article: Spellbook of identify
Casting this divination spell has the same effect as reading a uncursed scroll of identify (if cast at Unskilled or Basic) or a blessed scroll (if cast at Skilled or Expert).

Sitting on a throne
One of the possible throne effects is the same as that of reading a blessed scroll of identify.

Touchstone
Main article: Touchstone
A blessed touchstone will formally identify all valuable gems, worthless glass, and other gray stones rubbed on it. A gnome or archaeologist may also use an uncursed touchstone for formal identification. This is as good as the identify scroll or spell, except that it doesn't reveal the BUC status of the gem or stone.

Selling in shops
Selling or buying an item in a shop will cause the shopkeeper to tell you the appearance of the item. If the appearance is unique and not randomized, e.g. for most mundane armor and weapons, he will identify the item class for you. This is probably only useful in zen conduct games (also: wand of probing, potion of object detection).

Indirect identification
These methods require some knowledge (acquired from spoilers or experience), often lack universality, and don't always result in formal identification of an item as they sometimes give ambiguous information.

Price identification
Main article: Price identification
Although the price a shopkeeper charges is based on your charisma and slightly randomized, it is still helpful to some extent, but the main approach is to price ID using the selling price. This is very effective in categorizing rings, potions and wands for further identification using other means—even more so when direct identification is not possible, e.g. early games and illiterate games.
The simplest and most common application of price identification is identifying of the scroll of identify (the cheapest of the scrolls).

Weight identification
The weight of an unknown object is not nearly as useful as its price, but it can provide additional clues. This goes especially for cursed equipment you don't want to wear. In some cases such as levitation boots, it is unique within a price group. Another example is a gray stone in a box, which might be a loadstone.
One practical way of weight testing is to pick up just enough rocks and gold not to be burdened, pick up the object, and count the rocks and gold you need to drop to un-burden you. The spreadsheet File:Nh inventory weight.ods can count up your inventory weight.

Behavior identification
Passive  identification
This refers to discovering the properties of an item in a way that does not auto-identify the item.
For example, zapping an unidentified wand of cancellation at a dragon and hearing it cough; you know that it is a wand of cancellation, but the game will still give the randomized appearance as the identity of the wand.

Identification by using
Rings, potions, scrolls, and especially armor can be identified this way.

Some items are identified instantly when you wear, quaff, or otherwise use them. Many potions do this, as well as some rings and armor (e.g. boots of speed, elven cloak).
Some require a little time before you notice (e.g. ring of slow digestion).
Some are identified when some special thing occurs (e.g. rings of different resistances, amulet of reflection, amulet of magical breathing).
You can also use enlightenment to identify intrinsic-providing items.
Always remember to take the utmost care when use-identifying things. Check its beatitude using a pet or altar. Check potions using a unicorn horn (although some players just quaff and heal themselves, since dipping a unicorn horn into a potion of polymorph causes the horn to be lost). Don't read unidentified scrolls when confused or when wearing a precious piece of armor.
Things that can be easily identified this way are:

Cloaks – All the magical cloaks except cloak of magic resistance and (for invisible characters) cloak of invisibility auto-ID when you wear them. In this way, a non-invisible character can identify all cloaks unambiguously via wearing.
Boots – Fumble boots and levitation boots are mostly generated cursed. Elven boots (for characters without stealth) and speed boots auto-ID on wearing. Jumping boots are trivial to identify. If nothing happens when you wear the uncursed pair and you can't jump, you have either kicking boots or water walking boots, or (if you have stealth) elven boots. You can sometimes discern between them if you are a spellcaster, as kicking boots hinder your spellcasting abilities.
Whistles – Blowing the whistle unambiguously identifies it. If you blow a magic whistle and you have a pet on the level, it will become identified as one.
Identification by monster use
Humanoid monsters will use certain items; this can be helpful in identification.
They are sometimes created wearing an amulet of life saving which will auto-identify when it resurrects them.
They will quaff beneficial potions (healing, extra healing, full healing, speed, invisibility, gain level, polymorph) and throw harmful potions (acid, blindness, confusion, sleeping, paralysis). Generally potions will auto-identify when quaffed or thrown by monsters, but the potion of confusion is an exception. This is because thrown booze has the same effect; however, monsters do not throw booze.
They will read scrolls of create monster, earth, fire, and teleportation. If a scroll read by a monster has no visible effect, it was most likely create monster, and the new monsters were out of your visual range.
They will zap you with attack wands, and will zap themselves with wands of polymorph, speed monster, make invisible or teleportation. This can help distinguish wands of cancellation, make invisible, and teleportation, which cannot be told apart by engraving.

Wand engrave identification
Main article: Wand#Engrave-identification
To do the identification, engrave something in the dust and then try to engrave something else with the wand on the same square. Nine wands can be unambiguously identified. The rest will give ambiguous results. Unlike the scroll or spell, the number of charges will not be revealed, except that you know you've just spent one. A wand with zero charges will have no effect, possibly misleadingly, so do not use this method with wands in bones piles.

Dropping a ring into a sink
Main article: Sink#Identifying rings with a sink
Unambiguously identifies most rings, but destroys the ring in the process. This technique is useful when you have multiple rings of the same type or when you are desperately looking for a ring of slow digestion, which won't be lost in the sink.

Monster inventory identification
Some monsters are more likely to possess certain items. For example, nymphs are often generated with a potion of object detection, and elves with an elven cloak and elven boots.

Cheat
A very easy way to identify all your items is to save the game, copy the save file, paste it, reenter the game, quit, and have your possessions identified. Note the items you have, then rename the copy with the same name as the initial, and you'll have your game as if nothing happened. Same things for attributes.
This is considered cheating and is frowned upon.

See also
Curse testing lets you know the BUC status of an individual item.
External links
The NetHack Object Identification Spoiler (for version 3.4.3, but still largely correct).

This page may need to be updated for the current version of NetHack.
It may contain text specific to NetHack 3.6.0. Information on this page may be out of date.
Editors: After reviewing this page and making necessary edits, please change the {{nethack-360}} tag to the current version's tag or {{noversion}} as appropriate.