Twilight's Transformation

What happens when Twilight Sparkle begins transforming into some ungodly monster? Only Celestia can tell.

Twilight Sparkle is no ordinary unicorn. She has recently gained the title of Princess of Friendship and has now earned herself a castle in Ponyville. She even is now an alicorn! Life seems to be going her way.

But since when was her hoof so... big?