This immense moth has huge purple wings marked with spiraling black patterns that seem to shift and writhe.
Gloomwings are strange, moth-like natives of the Plane of Shadow. Despite their appearance, they are not vermin and possess a crude but serviceable intelligence. While gloomwings can be conjured via spells like lesser planar ally or lesser planar binding to serve as guardians or even mounts, occasionally a gloomwing will slip through a tear in the fabric of the planes and make the journey to the Material Plane on its own. A gloomwing loose on the Material Plane is active for 2 to 3 hours at dawn and again for 2 to 3 hours at dusk, preferring to spend the remaining hours of the day hiding in abandoned buildings, caves, or deep canyons or foliage where the shadows are thickest. During its periods of activity, it flies through the sky on the hunt for creatures to attack and implant its eggs in- the gloomwing does not need to eat, leaving this urge to propagate its species as its primary drive. For all the dangers a gloomwing presents, it is the creature's young that pose the gravest threat. These creatures are known as tenebrous worms (see page 260), and despite being the larval form of the adult gloomwing, are much more dangerous creatures. The fact that a gloomwing can lay several eggs a day if presented with enough living hosts makes them dangerous not for what they can inf lict themselves, but for what they can spawn.
The gloomwing is native to the Plane of Shadow and is often summoned to the Material Plane by spellcasters to act as a guardian. On occasion, a gloomwing slips through a tear in the fabric of the planes and enters the Material Plane on its own. The gloomwing is the adult stage of the tenebrous worm (see that entry). Female gloomwings lay their eggs in the bodies of slain victims. In 12 days, these eggs hatch, releasing 4-10 tenebrous worms. The ivory mandibles of a gloomwing can be pried or broken from its carcass and sold for 100 gp each. Gloomwings are aggressive creatures and fight from the air. They hover and flitter about an opponent, biting with their mandibles and slashing with their claws (they attack only with their two front claws; the other claws are too weak to be effective in combat). After the first round of combat, a gloomwing secretes a pheromone that calls other gloomwings in the area to its aid. The pheromone also acts as a weakening agent against non-insect creatures in the area.