He came from another world. He claims to be the Alicorn of Fate. Events inexplicably turn out in his favor. Ponies adore him for reasons they can't express. He counts bearers of the Elements among his friends, and one of them his lover. It seems he can do no wrong, and no evil befalls him.

Luna knows a threat when she sees one—and it has been allowed to go on long enough already.

(One of the three stories I was choosing between for Obselescence's Most Dangerous Game contest. I was trying to include as many of his prompts as possible in a single story with this one, but eventually decided to submit "Fading" instead.)