Unlike the regular wyverns, which you have to risk your life stealing an egg and hatching it, then go find a female Wyvern to knock out and take the milk from in order to raise your own wyverns, the crystal wyverns are super chill with you, and you don't have to steal any eggs and die a lot. All you have to do is mine some crystals, hop on it's back, and feed them the crystals until they are tamed. Way easier to obtain than regular wyverns which take a lot of time to obtain.