Everyone knows Fluttershy is the kindest, most gentle, loving pony in all of Equesteria. What they don't know is that she's also a killer. To protect Equestria from the true monsters, Fluttershy has learned how to kill, to be ruthless, all in the name of protecting her friends from harm.

This is the story of Fluttershy, and how she learned to be cruel.

As far as great ideas go, Twilight stumbled across the best one of all - throwing Pinkie Pie a shocking, frightening horror birthday surprise party! But as the six friends walk into the old dilapidated house on the hill, and the moon rises high above them, pranks turn sour and tempers boil, and the six friends find out that perhaps, the best ideas might not be so great after all. As the gang succumb to the dark horrors of the house and fall to machinations of their own design, Equestria gains another sordid legend to tell.