BSGS: Birthday Scenario Games Stories: Taking your birthday, or a character's birthday/premier date, putting it into the numerous Birthday Scenario Games, and trying to make a story out of the insane results. Mine turned out an alicorn because of that, despite trying to avoid that. Not a Gary Stu or a self insert.
Verdant Flare. To the castle staff and guard, he's a strange unicorn that showed up not long after Princess Luna's return. To a very select few, for now, he's known as the Alicorn Son of Celestia, returned from wandering and exploring. To the Mane 6, he's a pony with less social skills than Twilight Sparkle.
But no one seems to know anything about him: Where he's been, when he was born, why he left, or even who the father is. The answers will be more confusing than shocking, sans the final one.