# Chameleon

: chameleon 

Difficulty

7

Attacks

Bite 4d2

: chameleon 

Difficulty

7

Attacks

Bite 4d2

Base level

6

Base experience

73

Speed

5

Base AC

6

Base MR

10

Alignment

0 (neutral)

Frequency (by normal means)

2 (Quite rare)

Genocidable

Yes

Weight

100

Nutritional value

100

Size

Tiny

Resistances

None

Resistances conveyed

Causes polymorph

A chameleon:

 has no hands.

 is an animal.

 is carnivorous.

 is not a valid polymorphable form.

 is normally generated hostile.

Reference

monst.c#line2676

A chameleon, :, is the most common and well-known shapeshifter monster in NetHack.
Chameleons have a 1⁄6 chance per turn of changing forms: chameleons will change into an animal 2⁄3 of the time, and a random monster the rest of the time. A chameleon is immune to system shock and will continue to shapeshift as normal if you polymorph them while they are already shapeshifted, but can be permanently polymorphed and subjected to system shock if forcibly polymorphed while in their base form.[1]
Eating a chameleon corpse or tin causes you to polymorph, unless you have unchanging.

Contents

1 Generation
2 Strategy

2.1 Pets

3 History
4 Origin
5 Variants

5.1 SLASH'EM
5.2 GruntHack
5.3 EvilHack

6 Encyclopaedia entry
7 References

Generation
Chameleons are always generated hostile.
Several chameleons are guaranteed to appear within the Rogue quest: eight to ten chameleons are generated at level creation on the home level, five are generated at level creation on the locate level, and five are generated at level creation on the goal level. In addition, the section of the goal level containing the Master Assassin has a tin of chameleon meat in the leftmost room.
Chameleons are an invalid form for polymorph, and can leave their corpse upon death as normal regardless of their current form.

Strategy
Chameleons are quite capable of imitating various monsters that can either cast the summon nasties monster spell, most infamously arch-liches, or else can be generated by the spell themselves - this and many of the other possible out-of-depth forms can also spell death for the unfortunate, particularly in the late portions of the early game (e.g. Sokoban). As you progress throughout the dungeon and assemble your kit, chameleons gradually become less of a potential game-ender, but they remain an obstacle throughout the majority of the game, especially for Rogues on their Quest.
A suspected chameleon should be dealt with quickly whenever possible: wearing a ring of protection from shape changers or canceling them will force them to remain in their base form, which has weak defenses and can only do 8 damage at most by biting. A chameleon trapped in its base form can be permanently polymorphed without the ability to shapeshifter further.

Pets
Chameleons can be tamed  in the form of a domestic animal with the appropriate food, and will remain tame even as they change forms. Unfortunately, its usefulness as a pet is heavily limited, since it cannot be predicted when it will change into a useful form or one that is weak or else self-destructs to attack; it is typically better to polymorph them into another form using protection from shape changers.
Carnivorous pets eating a chameleon corpse may polymorph into something weaker or useless - try to avoid leaving those pets (especially purple worms) near chameleons or their freshly-made corpses. It also pays to mind what corpses you eat yourself, lest you cause yourself a lot of misery and lost armor.

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.

Pets will no longer eat shapeshifter corpses unless they are starving or on the verge of untaming.
History
The chameleon has been present in the game since Hack 1.21, a variant of Jay Fenlason's Hack.
When vampires became shapeshifters in NetHack 3.6.0, a bug was introduced that caused chameleons that polymorphed into any type of vampire to remain stuck in that form, leaving them unable to cycle between random forms or use the vampire's own shapeshifting. This was fixed in NetHack 3.6.1 via commit 885de11 and commit 45ba0ad.

Origin

Wikipedia has an article about:
Chameleon

Chameleons (or chamaeleons) are a distinctive and highly specialized clade of Old World lizards, with more than 200 species in in the family Chamaeleonidae. Chameleons are best known for their distinct range of colors and the ability to shift those colors, with variability from a shift in brightness or hues to employing a plethora of color-combinations - this is employed to avoid alerting prey or other predators such as birds and snakes, as well as in social signaling and reactions to temperature and other conditions, which depend on the species. Chameleons live in warm habitats that range from rainforest to desert conditions - various species occur in the mainland of Sub-Saharan Africa and Madagascar, as well as in southern Europe and across southern Asia as far as Sri Lanka, and some species have been introduced to Hawaii, California, and Florida.
Chameleons vary greatly in size and body structure, and are generally adapted for climbing, with a laterally-compressed body designed to distribute their weight, four-toed feet that have a pair of toes each facing forward and back, and a prehensile tail used to maintain stability. A chameleon's length can vary from as small as 15 mm (0.59 in) to 68.5 cm (27.0 in). The head of a chameleon often has a distinctive shape, and may include crests or horns on their brow and snout - their eyes are independently mobile, providing two separate, individual images of the chameleon’s environment for the brain to analyze; when hunting prey, they focus forward in order to coordinate more stereoscopic vision. Chameleons are primarily insectivores that feed using projectile tongues with a specialized bone and muscle structure to capture distant prey in as little as 0.07 seconds; some species can project their tongues more than twice the length of their body.
In fiction, the chameleon's camouflauge is subject to varying levels of exaggeration, with some fantasy works such as the Xanth series (from which the encyclopedia entry originates) extending this to full-on shapeshifting - the chameleon of NetHack clearly takes more inspiration from this latter "school" of portrayals. Chameleons are also often associated with subterfuge and deceit, being commonly employed as spy motifs.

Variants
SLASH'EM
In SLASH'EM, polymorphed monsters return to their base form upon death much like the player - this makes hostile chameleons far more dangerous, especially due to the amount of new monsters they can take the form of, since a polymorphed chameleon that is killed can quickly shapeshift again after resuming their normal form. This also makes tamed chameleons somewhat more useful, since they are at least likely to live longer and take on powerful forms that can aid you in combat.
In older versions of SLASH'EM, chameleons served as the first quest monster for the defunct Doppelganger quest, making up 55% of randomly generated monsters in the branch. Several chameleons would also be generated on level creation for each level within the branch: eight on the home level, three on each upper filler level, fourteen on the locate level, two on each lower filler level, and nine on the goal level.

GruntHack
In GruntHack, chameleons and other polymorphed monsters return to their base form upon death; while GruntHack does not have as many new monsters as SLASH'EM, the new additions are still more than lethal enough to make chameleons and other shapeshifters incredibly dangerous.

EvilHack
In EvilHack, chameleons also have several new lethal forms to take advantage of, and can revive after being killed; however, unlike SLASH'EM and GruntHack, a chameleon returned to its base form this way will be cancelled, preventing it from shapeshifting again.

Encyclopaedia entry

A small lizard perched on a brown stone.  Feeling threatened by
the approach of human beings along the path, it metamorphosed
into a stingray beetle, then into a stench-puffer, then into a
fiery salamander.
Bink smiled.  These conversions weren't real.  It had assumed
the forms of obnoxious little monsters, but not their essence.
It could not sting, stink or burn.  It was a chameleon, using
its magic to mimic creatures of genuine threat.
Yet as it shifted into the form of a basilisk it glared at him
with such ferocity that Bink's mirth abated.  If its malice
could strike him, he would be horribly dead.
[ A Spell for Chameleon, by Piers Anthony ]

 

References

↑ src/zap.c in NetHack 3.6.7, line 251