The firefriend, or giant firefly, is an intelligent insect that forms bonds with people and can learn to speak the common tongue. Despite its small size it can emit a very powerful beam of light as a weapon. (AD&D Monster Manual II, TSR, 1983) I skimmed past the giant firefly entry many times without realizing there was more to it. These could be valuable companions to a party, even better than the irascible fire beetles, especially in the era of dungeon crawls with precise resource management when adventurers tracked the use of each torch and flask of oil as time passed.
The firefriend, or giant firefly, is a well-regarded but rarely encountered creature found in temperate climes. Although this giant insect has only low intelligence by human standards, it is clever and shuns obvious enemies. Humans and demihumans of friendly disposition are sought as companions, however, for firefriends love to converse with them and to hear stories of a fanciful nature. A firefriend has small but sharp mandibles with which to protect itself. In addition, its glowing abdominal light, normally equal in luminosity to a torch, can be brightened and concentrated once every turn. A beam of greenish light about 3 inches in diameter and up to 14 feet long can be shot forth. Flesh struck will suffer 5-20 points of damage, one-half damage if a saving throw vs wands is successful. These creatures are not harmed by electricity or fire.
Firefriends speak their own language as well as the common tongue in most cases. They hatch in spring, grow to maturity by age 2, and live about 10 years or so. By age 1 or 2 they learn to converse with humans.