Based loosely on TBBBAP's review on Hearth's Warming Eve.

Phantom Horn has always been a bit different. He's a unicorn in an earth pony's body, he just knows it. Why couldn't he have the horn he was supposed to have? It's his destiny! But destiny, like his brother, comes just a bit sooner than expected when he's blessed with a horn of his very own! What will this unicorn supremacist do now that he has the power he's always wanted?

Spoiler: Not good news for non-unicorns.

Warning: This story has heavy use of profanity. Like, a lot.