In NetHack, when creating your character, you may choose a gender: male or female. You may also specify a default gender via the gender option in your configuration file. You can check your current and initial gender with ctrl + x, which shows your base attributes.
Your choice of gender affects a number of events in the game:
- Female characters can lay eggs when polymorphed into a monster that lays eggs.
- Any eggs found and carried by male characters have a 50/50 chance of hatching tame. Eggs found and carried by females never hatch tame. (Eggs laid by you always hatch tame, regardless of your current gender.)
- Male characters are seduced by the succubus, and female characters are charmed by the incubus. During seduction, incubi will put a ring of adornment on your hand if you have one, while succubi will steal them.
- Various messages will be slightly different depending on your gender, but with no effect on gameplay mechanics.
The Valkyrie is the only class that can only start as female, although any character's gender can be changed with an amulet of change.
Monsters can be gendered (including neuter), but this affects only the pronoun used to relate their actions.
In NetHack brass, female characters dressed as nurses can apply bandages in fewer turns than male characters. Female characters wearing "maid armor" (i.e. the maid dress, frilled apron, and katyusha) gain various benefits, while male characters will instead gain the aggravate monster property.
In SLASH'EM, Yeomen always start as male.
In SpliceHack, the player's interactions with succubi and incubi are not determined by their gender, but instead by their sexuality. Additionally, players may elect to play as nonbinary. A nonbinary player character is unique in the following ways:
- Nonbinary characters are more likely to receive armor removal prompts when being seduced by a monster.
- Nonbinary characters can't lay eggs.
- Eggs that hatch in the inventory of a nonbinary character always produce peaceful monsters.
- Nonbinary characters cannot be seduced by succubi or incubi, unless the player character is bisexual.