Congrats Olds on your first diamond egg. It's interesting that you only needed to use lower level dragons. I think we have smashed the theory that level 15 dragons and higher give you a better chance of getting rare dragons, and even more so, using level 20 dragons. As they say on myth busters: "myth busted!"
I wished I had have kept my collection of eggs rather than sell them off, as I have lost count of my total fails. I've probably only used a total of 50-60 gems since the quest began for diamond, however, my two crowned dragons are not proving as profitable as I would have imagined. I'm still grateful to have two more crowned dragons, and I only sold off the egg fails as I am working on crowning my level 19 river dragon next. (And I honestly didn't think it would take this long)

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