What would happen if a villain called Fluttershy's bluff? You know, she says something like “why don’t you pick on someone your own size?” or “You do not hurt my friends!” and they say “Oh yeah? And what are YOU going to do about it?!” or just pull a Moe from Calvin and Hobbes and say something like “They’d hit back” or “You ARE my size.”

Well if their in that position she's pulling that card I'm guessing lose horribly I remember the time she pulled that on a dragon if he didn't care about the stare they would have run or became lunch usually that's like her trump card so I don't see it ending many other ways