Travelers in the wild sometimes look to the skies to see the dark-winged shape of a wyvern carrying its prey. These cousins to the great dragons hunt the same tangled forests and caverns as their kin. Their appearance sends ripples of alarm through the borderlands of civilization.

Cousins to the great dragons, a wyvern has two scaly legs, leathery wings, and a sinewy tail topped with its most potent weapon: a poison stinger. The poison in a wyvern’s stinger can kill a creature in seconds. Extremely potent, wyvern poison burns through its victim’s bloodstream, disintegrating veins and arteries on its way to the heart. As deadly as wyverns can be, however, hunters and adventurers often track them to claim the venom, which is used in alchemical compounds and to coat weapons.

A wyvern doesn’t fight on the ground unless it can’t reach its prey by any other means, or if it has been fooled into a position from which aerial combat isn’t an option. If forced into a confrontation on the ground, a wyvern crouches low, keeping its stinger poised above its head as it hisses and growls.

A wyvern intent on its prey backs down only if it sustains serious injury, or if its prey eludes it long enough for another easier potential meal to wander along. If it corners a fleeing creature in an enclosure too small to enter, a wyvern guards where the quarry hides, lashing with its stinger whenever opportunity allows.

Although they possess more cunning than ordinary beasts, wyverns lack the intelligence of their draconic cousins. As such, creatures that maintain their composure as a wyvern hunts them from the air can often elude or trick it. Wyverns follow a direct path to their prey, with no thought given to possible ambushes.

A wyvern can be tamed for use as a mount, but doing so presents a difficult and deadly challenge. Raising one as a hatchling offers the best results. However, a wyvern’s violent temperament has cost the life of many a would-be master.

Aggressive and territorial, wyverns will engage in brutal aerial combat to defend their nests. One of a mated pair will travel very long distances to hunt while the other defends the aerie. 

Once trained, a wyvern can be a dangerous and tough steed. It does not form lasting bonds with its riders and can turn on the rider if it senses weakness. Wyvern riders typically must begin a regimen of drinking a diluted dose of wyvern poison so that over time they develop a resistance to the toxin. Alternatively, they will drink an anti-toxin potion for temporary protection if they do not have the time to develop a resistance.

A wyvern speaks its own language and can learn its rider's language with time and training.  Typically chosen by the Hobgoblin elite due to how tough they can be to bring down, but they can be raised and trained by anyone willing to take the risk. 

They are extremely strong with excellent endurance and carrying capacity. With a small sized rider, they typically have an 18-hour flying duration before needing an hour of rest. Medium sized creatures have a 15-hour flying duration. Like Griffons, they can't be trusted to carry anything other than prey in their talons.

They are not nearly as comfortable on the ground as they are in the air. They are passable walkers with poor endurance on the ground. Their walking can be sustained for an hour at a time (1 hour max with or without a rider)

These mounts hunt to sustain themselves only when necessary and eat meat exclusively.  The easy meals provided by their riders are the biggest reasons they can be tamed. A medium-sized animal is sufficient for a day's worth of sustenance. When fed or allowed to hunt larger game they can go for several days before needing to feed again. The rider cannot free the mount, but must hunt with it or it may choose to wander off and not return.  Typically, a large supply of meat is brought along on longer travels to allow the rider to get some rest and to encourage the wyvern to stay close. Wyvern mount stables are typically open top pens located on the top of fortress walls with an open supply of meat in cages to nearby to encourage these creatures to stay.