An insect is any monster represented by the character a.
- Other insects:
Insect-like creatures that are generally not considered to be insects include the s monster class, containing arachnids and other arthropods that aren't classified as insects in real life. The x monster class arguably also constitutes insects, because the class description is "xan or other mystical/fantastic insect", but these are not treated as insects in, for example, the summon insects monster spell.
It is not a good idea to genocide any species of insect, as they provide a valuable barrier between you and the tougher monsters in the Sanctum and Astral Plane. Some players make an exception to genocide soldier ants, as they pose a particular hazard in the early game.
See the a (monster class) page.