Potion of invisibility

!
Name	invisibility
Appearance	random
Base price	150 zm
Weight	20
Monster use	May be used by monsters as misc items.

A potion of invisibility is a type of potion that appears in NetHack.

Generation

Randomly generated monsters may receive a potion of invisibility as a miscellaneous item: if an invisibility item is chosen for that monster's starting inventory, it has a ⁵⁄₆ chance of receiving the potion, unless it is not hostile and you cannot currently see invisible.

Description

Quaffing a potion of invisibility turns the drinker invisible and will auto-identify the potion, with effects varying depending on beatitude and whether or not you or a monster drank it: A blessed potion grants you permanent invisibility, while an uncursed potion grants you temporary invisibility for 31-45 more turns. A cursed potion has the same effect as an uncursed one, but will additionally aggravate monsters by awakening all sleeping and meditating monsters on the level. The potion will have the same effects if you are blind, already invisible or else wearing a mummy wrapping, but does not auto-identify the potion and prints a different message.

Monsters will use this potion, auto-identifying it if you witness one doing so. A monster that quaffs this potion becomes permanently invisible unless it is wearing a mummy wrapping; the same effects occur if a monster is hit with a thrown potion. If a monster quaffs a cursed potion, it aggravates you: the invisible monster's position will briefly be displayed on the map along with a message, and you are awakened from any unconscious state. Peaceful and tame monsters will not quaff the potion if you cannot see invisible.

Inhaling the vapors from a potion of invisibility will cause you to become invisible very briefly and auto-identify the potion if you saw it break.

The following information pertains to an upcoming version (NetHack 3.7.0). If this version is now released, please verify that the information below is still accurate, then update the page to incorporate it.

As of commit f83a57c, the quaff effects are as follows:

Case	Effect
blessed	You have a 1⁄30 chance of becoming permanently invisible (1⁄15 if already invisible). Otherwise, you gain (3d100)+100 (more) turns of temporary invisibility.
uncursed	You become invisible for (6d100)+100 (more) turns.
cursed	You become invisible for (9d100)+100 (more) turns. All sleeping and meditating monsters on the level are awoken.

Strategy

Uncursed potions of invisibility are useful for escaping or clearing out tricky combat situations early in the game, but will usually not be relied on as often once a character gets off the ground. A blessed potion is a quick and easy way to attain permanent invisibility if you are not concerned about handling shopping or else have a means to do so. If you are already permanently invisible or do not plan to make permanent use of the property, non-cursed potions of invisibility are a good prime candidate for dilution.

A cursed potion of invisibility, on the other hand, is useful for remotely waking up covetous monsters such as your quest nemesis or any of the demon lords and princes in Gehennom. This is best done while standing on the upstair, both to save you a trek across the level and to block off their escape while you fight them.

History

The potion of invisibility first appears in Hack 1.21,a variant of Jay Fenlason's Hack, and also appears in Hack for PDP-11 and PC/IX. It is included in the initial item list for Hack 1.0.

Messages

Gee! All of a sudden, you can't see yourself.

You quaffed a potion of invisibility.

For some reason, you feel your presence is known.

This is additionally printed if you quaffed a cursed potion.

Gee! All of a sudden, you can see right through yourself.

As above, but you have see invisible.

Far out, man! You can't see yourself.

You quaffed a potion of invisibility while hallucinating.

Far out, man! You can see right through yourself.

As above, but you also have see invisible.

You have a peculiar feeling for a moment, then it passes.

You quaffed the potion while blind, already invisible, or else wearing a mummy wrapping.

You have a normal feeling for a moment, then it passes.

As above, while hallucinating.

Suddenly you cannot see <monster>.

A monster became invisible by quaffing the potion.

<monster's> body takes on a strange transparency.

As above, but you have see invisible.

<monster's> body takes on a normal transparency.

As above, but you were also hallucinating.

For some reason, <monster's> presence is known to you.
You feel aggravated at the invisible <monster>.

A monster quaffed a cursed potion.

Aggravated, you are jolted into full consciousness.

As above, but the effect also roused you from unconsciousness.

For an instant you couldn't see yourself!

You inhaled the vapors of the potion while not blind.

For an instant you could see right through yourself!

As above, but you have see invisible.