When stealing wyvern eggs always be on a griffin since griffins can out run wyvern with their dive and also take a bait bird that you don't mind losing.eg. like a pteranadon with high health. When stealing the egg take a whip with you so you don't need to dismount and when you get the egg fly out immediately check if any wyvern are chasing you if there are wyvern chasing whistle attack target with your pteranadon the pteranadon will distract and you can make a quick get a way. Hope this helps

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