Yep. Can't remember the story, but the idea is the human turned pony is in a time loop (maybe?) and his first instinct is to kill Applejack with a plank while she is sleeping. He eventfully 'dies' when Rainbow Dash murders him when the Main 6 find him which restarts the time loop.

That's all I can remember, so, anyone know?

7677699
No clue as too the story but that sounds funny and would also love to know that story as well