Wyvern

Similar to the Drake, the Wyvern is encountered much later on. It bears many of the Drake's abilities and characteristics, but is more closely related with the Lightning element. It is able to let loose a stream of electrical and stormy energy in place of the usual Fire Breath. The stream itself does no damage, however it will incapacitate anyone caught in (since they'll try to protect themselves from the wind). Moreover, when the wyvern uses this from above at a downwards 45 degree angle, staying inside for too long will propel the victim high upwards, high enough that it will receive falling damage upon landing.

Like the Drake (and presumably the Wyrm), it can both shout to one-shot every pawn in your party, and try to grab you and/or your pawn. If it grabs you, it will smash you on the ground for high damage. If it grabs a pawn, it will hypnotize/brainwash them after a delay of 10 seconds (guesstimate, please confirm). During this delay, the arm holding the pawn can be attacked to make it release the pawn after damage. If he does succeed, the pawn will turn on you and your allies and try to damage you until killed. Halidom also seems to cure this effect.

The heart is on its back. While it can be damaged by attacking anywhere on its body, its hp will go no lower than 1 hp until the killing blow is landed on its heart. It is resistant if not immune to lightning damage and weak to fire.

While the Wyvern is aloft target its head with a strong ranged attack such as Mighty Bend. This will cause the dragon to fall to the ground making its heart an easy target. One can then grab hold before it takes off for more quick damage.

It is possible to break both horns on its head, which will result in Dragon Horn material drops. I also remember both of my kills dropping some kind of scale (the image of the object looked like a green Seeker's Token) and Indurated Dragon Blood.

The Wyvern takes approximately 7 in game day to respawn.

Locations (post-game)
Gran Soren southern gate at night. Two Wyvern can be seen flying in the distace.

Conquest Road north of Gran Soren close to Windbluff Tower. When you approach it will take flight, continue north and try to lure it down.

Atop Bluemoon Tower, where you once killed a Griffin with an expedition party.