Board Thread:Questions and Answers/@comment-1577342-20150619232645/@comment-24577221-20150620014459

You can get a rare that way: if A + B can give you A as a result, for whatever reason, it can give you a Rare A instead if it's available when you do the breeding. But so far as we know, the odds are no better than if you were to breed a T-Rox by any other means. I don't recall... does, say, Noggin + Maw ever fail to give you a T-Rox? If Noggin + Maw is guaranteed to give you a T-Rox, you might as well just do that than T-Rox + Noggin, which might take a few extra (brief) breeding rounds.