Not sure if I'm late to the party on this one, but I revisited someone whom played with my dragons (A community member who's island name is Varos)and after I played with three of them I saw a bizarre egg in his nest. I would speculate it is a some kind of "Broken Heart" dragon, and as far as colours are concerned all I can think of is red/blue. If anyone can say what they used wehn they bred this dragon please post it below. Here's a pic of the egg I saw.(You'll have to click it to make out the egg design)
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