As cool as Nightmare Moon and Discord are, it's unlikely we'll be seeing them again. If you could create (or already have created) another villain for the FiM universe, what kind would you make?   It can be a simple bully like Trixie, a serious threat like Discord, or even a psychopath like the infamous Pinkamena. Don't worry too much about whether it is kid-friendly or not. Just make it interesting!