This Is my guess/hypothesis if you leave a wyvern egg sitting on its nest for a long time and you get it after so long you have a big chance of getting triplets. Trust me I did it my first wyvern egg and I got triplets. Up so people know if they dont know they wont do it and get triplets
I got a level 150 lightning egg and I was so excited to hatch the egg...that when I went to put the egg down I accidentally ate it instead. :( ps4 users: R2 ISN'T GONNA DROP THE EGG YOU'RE GONNA EAT IT LIKE ANY OTHER EGG. REMEMBER THIS. LOGIC BEFORE EXCITMENT.