The Wyvern is a green dragon found at the end of Path A in the Old Capital. He will bite at you, shoot fireballs, and do a flying charge causing a knockback. When his health is reduced to less than half, he will then call for aid from some female wyverns. Killing the female wyverns will produce wyvern eggs for easy points.
Females have much less hitpoints and will spawn endlessly once the main wyvern has used its call. They will attack with their tails and a breath attack that leaves an acid puddle below its target. Touching the puddle even after the initial attack will deal damage, making the narrow bridge the fight takes place on even more dangerous. They are guaranteed to drop three wyvern eggs on death.
One sidequest has you to collect twelve wyvern eggs before killing the male wyvern.