Shriekers

''Above distant mountaintops, winged shadows flicker between massive storm clouds. The crew realize their mistake and the wind mages begin correcting course, but it is far too late for that. Hardened mercenaries shake as they ready their weapons and pray. In a flurry of motion, a swarm of leathery abominations descend upon the doomed vessel, and their horrific noise drowns out the sailor's cries. In minutes, only pieces of armor and shattered bones are left, cleaned of flesh and marrow.''

Leech-like flying predators, shriekers are a common threat to settlements and trade vessels across the known world. Their snake-like bodies and both pairs of wings are lined with razer sharp spines, and their mouths are thick, meaty suction cups lined with needle-like teeth. When they detect prey, their fangs vibrate to create a high-pitched whine that alerts other shriekers of the potential food source. They breathe through their skin and have a very low tolerance for the fog, and as such they will die should they come into contact with it.

Shrieker species come in many shapes and sizes, but generally fall into a few categories. Vipers are the smallest, barely larger than a small eagle, but they have the greatest tendency to swarm. Pythons are the next size up, with wingspans reaching up to 3.5 m. They are barely capable of powered flight and primarily rely on the strong storm winds for takeoff and maneuvering. There are rumors of larger specimens, known as cobras, but they are often dismissed as sailor's tales.

Combat
Shriekers display signs of a primitive intelligence and will simply swarm a target until either the target dies or enough of them die. The numbers vary, but they will start backing off when around twenty percent of them are killed. There are three ways to ensure some chance of survival when fighting shriekers directly.
 * Cover oneself head to toe in full-plate and hope they lose interest when they break their teeth on the armor. This can be risky, as there is always the chance of one of them slipping through the armor and consuming from the inside out.  They are too fast and agile to hit most of the time, but one can get lucky when trying to strike them.
 * Try to pick them off from a distance with projectiles or magic and hope enough of them are killed before they can close the gap. To increase survival odds, one should assume positions upwind of the swarm to add valuable seconds to the shrieker's travel time.  Apologies to those downwind of the swarm.
 * Then there is the candle approach, which is to have an empathic link to the shrieker's natural predator, the shadow moth, and weave in and out of the swarm as naturally as breathing, while drawing their attention away from others. Hope their combat fee is affordable.

Usage
Shrieker flesh can be safe to eat when cooked until charred, tough and rubbery, meaning the only people foolhardy enough to actually eat the stuff are either desperate or candles. The skin of shriekers is hard to work with and has a strong odor of putrid flesh, but it can be worked into bands of durable, yet comfortable leather. Many parts of the shrieker are used in alchemy and will fetch a decent price. From blood and venom to powdered bones and teeth to dried organs, hardly anything is wasted from the shrieker's body.

Varieties

 * Naga Viper

Environment
Shriekers make their rookeries in caverns high above the fog with access to strong winds for ease of takeoff. Passages are covered in scratches from where their spines rub against the stone. Lining the walls of the deepest chambers are thin, white egg sacs that resemble skeletal structures, surrounded by pools of regurgitated flesh. Once the eggs hatch, the shrieker larvae will writhe into the slurry and consume everything within reach. Within a week, they will develop into viperlings with dull ridges where their spines will be and fins that will develop into wings. After their wings unfurl they will join the rest of their kind in terrorizing the skies.