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got a candy from feeding berry
I put my Blissey in a gym, then fed it one berry to max it. I got a candy for it. I tried feeding another mon in the gym, didn't get the candy.
Have you seen that? if that is systematic, like always get a candy for maxing a owned mon or maxing just after entering the gym, that would be awesome, expecially for Blissey, Snorlax...