Bainligors are a species of humanoid bats created for Advanced Dungeons & Dragons in issue #227 of Dragon Magazine. Flightless, unlike official batfolk races the Desmodu and Nycter, bainligors are small (3' to 6') humanoids with long hairless arms, viciously clawed fingers, furry bodies, and the distinctive heads of echolocating bats. Needless to say, even the most charitable of souls is hard-pressed to call a bainligor anything other than "hideous".

A primitive, tribal species, bainligors inhabit the upper regions of the Underdark, pursuing a nomadic existence in search of water and food, which to them consists of insects, spiders, rothe, and edible fungi. And that's being generous; bainligors are consummate scavengers, feasting on insects, detritus, rotting flesh, and literally anything they can shove into their mouth. Rather than a source of shame, this scavenging, wandering existence is a source of pride among the bainligor, for they believe that they can survive anywhere, on anything, whereas others are tied to the earth by their possessions, their cities, and their weakness for special foods. Eating noxious foods is a source of many bainligor boasts.

Bainligors are a gerontocracy, where leadership goes hand in hand with age; the older a bainligor is, the more respect that he or she commands from his/her fellows. This may be partially because bainligors have a strange racial trait that causes them to grow increasingly large and powerful as they age; the older a bainligor is, the bigger and nastier it is. This culminates in the Revered Ones; ancient bainligors who reached the end of their living span and were instinctively compelled to leave it and seek out a dry, empty cavern, where they died and spontaneously came back to life as a powerful mummy-like undead creature. As their name suggests, these creatures are regarded as living gods by their fellows, who obey them fanatically. Revered Ones serve as mighty chieftains, war leaders, priests, and guardians of their descendants; the strongest of them may rule a swarm of bainligors for generations. About 10% of bainligor Revered Ones spontaneously develop spellcasting abilities after their transformation, which adds to their might.

Despite their unimposing stature, bainligors are not easy to fight. In addition to their wicked claws and fangs, they can focus their echolocation, which they use to hunt in eternal darkness, into a deadly sonic blast attack, and they have an uncanny ability to dodge missile attacks.

Though bainligors can speak Underdark trade common, most of their speech is too high-pitched for others to hear. Even if one speaks in a voice low enough to be heard by other races, its voice remains a high-pitched squeak. As a result, bainligors rarely speak with outsiders and carry on less trade than other races. Most of what they have is of little value; bone and stone tools, tanned hides, and small quantities of food are their usual treasures.

Tales are told of the Deep Tribes, those who starved until they were reduced to nothing but dozens of the Revered, who still hunt in great swarms, not for nourishment but for the joy of their great strength and the fear they cause in others. These are likely nothing more than myths told to bainligor young, for such sightings have never been confirmed by sages or savants of the Underdark races.