|Environment||Any land (Shadow Plane)|
Source: The Diaspora Strain, pg(s). 59
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Tenebrous worms are the larval forms of gloomwings, a species of moth-like outsiders with animal intelligence native to the Shadow Plane. Despite this, young tenebrous worms are much more dangerous than adult gloomwings.
A tenebrous worm resembles a pallid, armoured caterpillar. Its internal organs seethe and roil with shadowy energy and fluids that leak out of its carapace, forming dark bristles on its back. These bristles are capable of piercing the flesh of foes and inflicting a deadly poison.
Gloomwings lay their eggs in living creatures; when they hatch, the emerging tenebrous worms will devour the host as their first meal. Sometimes, the strongest tenebrous worm in a brood devours its siblings as well. When a tenebrous worm bites prey, its saliva melt flesh into edible shadows; after a tenebrous worm eats enough, it will seek out a dark area to pupate in a cocoon, which exudes darkness, before maturing as a gloomwing after several days.