Wyverns are draconic creatures artificially grown by ancient, powerful dragons to serve them for a variety of purposes, most of them related to war. Wyverns along with dragonborn retainers constitute the main invading force of most dragons, and their presence heralds the imminent coming of a conquering wyrm. Primitive civilizations who know about the existence of dragons often confuse them with lesser versions of them, however while wyverns do possess high intelligence, they do not have the ability to communicate with creatures other than their masters and other wyverns, sharing hive-like consciousness between themselves. They are living weapons, their only purpose being to serve their masters without fear, hesitation or mercy.
Wyverns, unlike dragons and other draconic creatures, do not have a base anatomical structure. They reach potential slave-worlds as pods, crash-landing and burying themselves into the ground. They may lay dormant for years, even centuries until they sense their master’s proximity and become active. During this time, the bio-mechanical pod gathers information from the planet’s environment and grows a suitable shape for the creature. The only features wyverns share in common are a breath weapon, the capability of flight (ranging between anything from merely hovering to super-sonic flight), draconic features such as scales, talons and horns, and their repulsor field: an invisible, force-field barrier that protects the wyvern from most conventional attacks save for brýgh weapons, as well as magic weapons and effects. Once a wyvern’s repulsor field is neutralized, there is a limited time window in which it is susceptible to conventional weaponry before the creature generates it again.
Wyverns whose master is destroyed continue to carry out the task they were last appointed to complete to the best of their ability, or remain inactive until the conditions to continue such task are met. They no longer possess a hive-mind connection and their perception is limited to their senses.