Pinkie Pie's abilities have confused ponies for as long as she's been around. Her very existence is an oddity, and maybe there's a reason for that after all.

From the strange way she showed up to her parents, to the moment something went wrong when Twilight practiced a new kind of magic around her, Twilight has found one thing consistent in her new studies of Pinkie Pie:

Things are not always what they seem to be. Neither are ponies.