When taming you do not need a crossbow follow one until ot lands and jump on its wing or tail and run up its body until your standing between its shoulders roughly where you would be if you were riding it there is some room for error in this from there you can feed it crystals and aslong as it doesn't fly into anything that would cause you to be pushed off you will not fall off i have tamed 6 wyverns this way and it is almost to easy

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