This is a prequel to undeliverable. Why did Derpy go missing? Where did she go on vacation? Only one pony has the answer, the same pony who is dictating the letters. She is Twilight Sparkle, the Princess of Friendship.
I am the author. I write words. You are the reader. You bring the words to life, along with my messages. All I ask of you is that you bring my words to life...and learn from my life.