Cheez, wanted to suggest a mug for Glim, "Twi's #4 redeemed villain." but not sure if the right number. Nightmare Moon I discount as not reformed but a vanquished possession of some kind. So #1 Discord, (not Gilda, that's RD's), #2 Trixie, #3 Sunset Shimmer. Nopony else I can think of fits the criteria.