Beautiful. The song is pretty... if kinda spooky... and this is just the sort of thing I can picture Princess Luna doing. (I'm sure she won't let the little colts come to any harm... creepy as she seems to be here.) Silk-smooth animation, too with some very nice effects.
Only... did Luna look a little cross-eyed in places to you? Kinda like she was channeling Derpy?
Beautiful. The song is pretty... if kinda spooky... and this is just the sort of thing I can picture