First only the Lord of a castle can ride a Wyvern freely in the sky.
Wyverns can be mounted speaking to the Wyvern Manager that is on the top floor of the castle.
To ride a Wyvern, the clan leader must be riding a strider when speaking to the Wyvern Manager, noting that to ride it you consume Crystals B-grade.
To ride a Wyvern, you can attack no mob, but you can use the special ability of the Wyvern Breath attack to attack other players.
You can not pick up items while astride a Wyvern, nor use skills.
When you dismount Wyvern it will disappear soon after.
If the Lord’s Castle change while you’re riding the Wyvern, you will be automatically dismounted from his dragon.