A werecreature or lycanthrope is a type of monster that appears in NetHack, and can refer to any of a group of shapeshifters that change back and forth between animal and human forms, and can infect characters with lycanthropy via their bite.
The werecreatures consist of the following monsters:
All werecreatures are chaotic and omnivorous humans that have carnivorous animal forms. They can be seen via infravision and move at the same speed as an unhasted and unburdened player character in either form, and possess enhanced regeneration, poison resistance, drain resistance, and a weakness to silver. Werecreature shapeshifting is largely involuntary and causes them to drop excess weight and armor that cannot be worn in animal form, and werewolves additionally tear through body armor - this and the other qualities mentioned also apply to the player character if they become a lycanthrope, starting at the time of infection.
In human form, werecreatures attack using their fists or any weapons they are carrying, and will seek out and pick up other weapons and food. In animal form, they attack via bites that can infect a character with the same type of lycanthropy they possess, and can also summon monsters of the same or similar species as them when in melee range; they also respect Elbereth in animal form. If a character has protection from shape changers, werecreatures will still shapeshift, but immediately shift out of animal form on the next available turn and are prevented from infecting the character by the property; they also effectively cannot call for help, since they will not remain in animal form long enough.
Werecreature corpses are poisonous to eat, and eating a werecreature corpse or tin confers lycanthropy to a character - other monsters cannot be given lycanthropy, but will avoid eating the corpse unless they can resist poison (or eat by engulfing, as with gelatinous cubes).
Randomly-generated werecreatures are always created hostile and in human form. They are not a valid form for normal polymorph.
When a werecreature summons help, d5 monsters of the appropriate type are created around them with the probabilities in the following table:
Characters infected with lycanthropy can also summon tame monsters this way by using the #monster extended command while they have 10 Pw to expend - the monsters summoned depend on the werecreature that infected them.
Werecreatures are one of many lethal early game threats: even the weaker lycanthropes can cause major inconveniences at best and deadly circumstances at worst if they manage to infect you with their bite, and being pinned by hostile monsters can lead to death fairly quickly without a means of scaring them off such as Elbereth. If you happen to find a silver weapon, it is a good idea to keep on you at all times, since even silver weapons with restricted skills can deal enough damage to kill a werecreature quickly - if you get infected, however, you will be unable to handle silver objects of any kind, and the damage from re-touching them and certain other items (i.e. cross-aligned artifacts) can be potentially lethal.
Pets can assist in dealing with werecreatures, who will only call for help when attacking you and cannot infect other monsters. Additionally, summoning is less immediately dangerous in hallways, as you can more easily deal with two or three monsters simultaneously. If at all possible, avoid engaging in melee combat with a werecreature in animal form unless you have an effective way of curing lycanthropy - eating a sprig of wolfsbane, quaffing holy water, and praying successfully can all remove the infection.
Lycanthropy itself is typically unwanted due to animal forms having much lower AC, HP and carrying capacity, as well as shedding weapons and armor (and destroying body armor if turning into a wolf) and losing the use of your hands. However, there are some applicable strategic uses for lycanthropy as a property, usually involving summoning tame monsters for polyfodder and slotless drain resistance - see the linked article at the top of the section for more details.
The concept of humans shapeshifting into animals has been a common concept in folklore among various human eras and cultures, while "therianthropy" and related terms as a means of describing specific forms of human-animal shapeshifting have been in use since the early 20th century. Some lycanthropes in their animal forms, or else other animals that can shift to a human and/or humanoid form, are referred to with the suffix "-were", e.g. a wolfwere can shift from the base form of a wolf to that of a human or a "wolf man".
- You feel feverish.
- The player was bitten by a werecreature and infected with lycanthropy.
- The <werecreature> summons help!
- The werecreature summoned monsters of the same class to assist it.
- You feel hemmed in.
- As above, except one or more of the new monsters spawned outside of the character's sight.
- You hear a <jackal/wolf> howling at the moon.
- A werejackal or werewolf is present on the current level, and has shifted to animal form out of your sight.
- The <werecreature> whispers inaudibly. All you can make out is "moon".
- You chatted to a werecreature.
In SLASH'EM, the Lycanthrope is a playable race, starting with (not hungerless) regeneration and lycanthropy (always a werewolf) which cannot be removed, but can eventually be controlled. They may only be chaotic, and any silver weapons in one's starting inventory (such as with Undead Slayers) will be reverted to their non-silver counterpart.
Additionally, there are several new lycanthrope monsters in SLASH'EM: werepanthers, weretigers, werespiders, and weresnakes.
In 1573, the Parliament of Dole published a decree, permitting the inhabitants of the Franche-Comte to pursue and kill a were-wolf or loup-garou, which infested that province, "notwithstanding the existing laws concerning the chase." The people were empowered to "assemble with javelins, halberds, pikes, arquebuses and clubs, to hunt and pursue the said were-wolf in all places where they could find it, and to take, burn, and kill it, without incurring any fine or other penalty." The hunt seems to have been successful, if we may judge from the fact that the same tribunal in the following year condemned to be burned a man named Giles Garnier, who ran on all fours in the forest and fields and devoured little children, "even on Friday." The poor lycanthrope, it appears, had as slight respect for ecclesiastical feasts as the French pig, which was not restrained by any feeling of piety from eating infants on a fast day.