On Saturday's two-part finale of My Little Pony: Friendship Is Magic (10 a.m. ET/7 a.m. PT, Hub Network), Twilight Sparkle isn't feeling so great about her princess-y worth after Princess Celestia bypasses her and chooses Discord instead to track down a villain. Having identity issues is tough for any pony, but fortunately her fellow princesses are there to give her a boost.