What fantasy story or game would be complete without a trip into a deep, dark, dank cave? Some of them, I’m sure. This is going to be just a single part of my cave dwellers entry, because there’s just so many types of animals that live in them that it’s hard to choose just three. Today we’re going to focus solely on Troglobites, or fauna that live completely within cave systems their entire lives, so we won’t be covering bats, bears, or any other mammals. There are surprisingly no mammals that live their entire lives inside caves, although some may dig tunnels.
Let’s take a look at three of my favorite troglobites, with a fantasy flair, and feel free to use them in your own work. But you already knew that, didn’t you?
The White Cave Velvet Worm
Velvet worms are like a weird cross between a worm and a centipede. They’re incredibly vulnerable to drying out and dying, so they can only feed for a few hours at a time each day before they have to return to damper areas. This remains true for our fantasy version, as will most of the characteristics and behaviors of the White Cave Velvet Worm. What shall change will be its size.
Velvet worms tend to grow up to about 8 inches in the real world, but in our fantasy version why don’t we make them more like 36 inches long? At three feet long, it’ll be more of a threat for larger animals, and even humanoids, as velvet worms are pack hunters. While their brains are quite small, they live in social groups and have a dominant/submissive system with females serving as the alpha of the group.
Velvet worms hunt using air currents, with small changes being detected by the two antennae on their head. Once prey is detected, velvet worms sneak in and attempt to ‘measure’ the size of their prey by tapping it with their antennae very stealthily. Hungry velvet worms sometimes won’t bother and will just attack the first bit of prey they find. With our version, this could include humanoids.
Once the prey is located, the worms use two high pressure orifices on their head that emit a sticky glue-like substance. These two streams hit each other in midair and turn into a ribbon-like net of organic glue that quickly hardens. They’ll even target limbs on larger creatures, pinning them down before they can escape or fight back. Once ensnared, one worm will bite a soft part of the prey and inject its saliva, killing the prey and starting to digest it.
Our Giant White Cave Velvet Worms hunt this way as well, taking any prey they can find inside their caves. Countless treasures and magic items could collect in their lairs, completely useless to the worms, but quite valuable to anyone smart enough to get in and out without getting eaten as well. Of course, the worms themselves could be prey to something even nastier, so retrieving the treasure may be impeded by the…
The Great Grandfather-Long-Legs
Did you know that Opiliones are often confused with spiders, but are actually more related to pseudo-scorpions? They have a single fused middle section and only a single pair of eyes. There’s also the misconception that they’re super venomous and would kill you, if only they could pierce you with their tiny fangs. In truth, they have no venom and they lack hollow fangs for injecting anyway. That doesn’t mean they wouldn’t be dangerous if they stood five feet high with a leg span of nearly 10 feet.
Omnivores and scavengers, The Great Grandfather-Long-Legs has been seen eating giant velvet worms, amphibians, fungi, and even some cave plants. They’ll converge on a larger dead corpse and scavenge on its soft bits, although they are rather skittish and won’t stick around if threatened.
The real danger comes from a recently mated male Opiliones, who will viciously guard their nests from predators. Often a male will have several clutches from different females he is responsible for. While Opiliones are not as social as velvet worms, they will still form colonies that tolerate each other’s presence. So kicking the nest may not result in a hundred coordinated attacks, it would still not be a smart move.
This huge version of the real world creature still doesn’t have venom or the hollow fangs required to inject it, but they do have their grasping, claw like mouth that could easily grab and remove chunks of flesh before you can even react. In a rather odd contrast to this viciousness, they will often take time to calmly clean their legs with their mouth, much like a cat.
The Large Shelled Snake Snail
These snake snails are not exactly based on real world creature. They are more of an amalgam of different land snails, the idea of a land snail itself, if you will. So it is a shell-covered, hermaphroditic, air breathing, land dwelling mollusk that can be either herbivorous, omnivorous, or carnivorous. This fantasy species lives in the edges of caves, where it can find food and prey more easily, but retreats further under ground to mate and lay eggs.
Snails form their shells from calcium they digest from their environment. Our snails, who only grow to the size of an adult human’s head, create quite large shells that require a large amount of calcium to create. This means that some cave walls may have been smoothed not by water, but by snake snails. Because their shells are so large and heavy, snake snails have evolved to have a longer body than normal that allows them to quickly leave their shell, grab prey, and return to the safety of their home.
These large snails are not a direct threat to people, but their rows of tiny teeth can break the skin, leaving itchy bites. If enough snails were to attack, say, a sleeping adventurer, they could cause some damage. The slime the snails exude is also a threat, not just from slipping and falling, but some cave snake snails have been known to have slime that had psychoactive substances which humans do not react well to. Similar to ergot poisoning, the extreme hallucinations can lead to panic and death if the victim isn’t monitored closely.
An amusing, although still terrifying, aspect of snails is in their mating habits. Snails are hermaphrodites, which means they contain features of both sexes, and during mating there is an odd thing that happens. The ‘male’ snail fires what is called a love dart, a hardened spike that can be up to 1/5th of the snail’s length and contains hormones that increase the ‘femaleness’ of the receiving snail. What this means for people is that you might get a 3 inch long spike fired into your skin from a sex-starved snail. This could also be used as a defense mechanism, and love darts from a large group of snails could prove fatal.