Old players vs newer players
I've noticed today some of us that played before mastery are potentially at a disadvantage to those starting in the mastery phase. For instance, I made many of my birds, and especially my favorites, Master level with LCs back in the day. Mathematically this hurts you. You would take a bird from elite to master for a 20 % gain, but you are better off taking a "virgin" bird from egg to level 10 mastery. We had 3 chances to upgrade by 20% but the new method increases twice as often at 10%. These birds have much greater attack and defense. I recently picked up bard and SeaDog and by the time they reach mastery 10 they will be 50% stronger than my previous favorite birds. I've noticed you can restart your classes potentially, well at least the offer us there. Worth it? Does it start over your mastery for that class? Worth a though.