Cunning Predators. The cave wyrm often hides in the shadows of complex tunnel systems, long whiskers guide them through their tunnels. They are adept diggers and are able to dig through solid stone, their thick scaly skin protecting them from falling stones or crushing weight. They often use intimidation or voice mimicry to guide or lure their prey and promptly chase them into a corner. When their prey has nowhere else left to go the wyrm sprays them with their acid breath. The cave wyrm, when lurking in the shadows, is often likened with an alligator or a giant catfish in appearance. 

Ravenous Marauders. Cave wyrms are always hungry and ready to eat absolutely everything. They devour undead, plant creatures, or anything organic. When feeding, they treat all nearby creatures as both a threat and the next course. What alliances they do make only last so long as their allies make themselves scarce when the wyrm feeds. They can be bribed with food, but other attempts at diplomacy typically end in failure. Wise allies keep a cave wyrm well fed. 

A Hard Life. Limited food underground makes truly ancient cave wyrms almost unheard of. The eldest die of starvation after stripping their territory bare of prey. A few climb to the surface to feed, but their sensitivity to sunlight, earthbound movement, and lack of sight leave them at a terrible disadvantage. Cave wyrm coloration darkens with age, but it always provides good camouflage against stone: white like limestone, yellow, muddy brown, then black at adult and older categories. Mature adult and old cave wyrms sometimes fade to gray again.