While Twilight Sparkle is in Canterlot, she overhears the truth, and she doesn't like what she hears. Faced with knowledge she never thought about until then, how will she react, and how will the speaker explain how the world is much harsher to some than others.

Cover art can be found here http://th08.deviantart.net/fs70/PRE/i/2012/321/9/0/king_sombra_by_tsitra360-d5lacsv.jpg

And of course, all rights to My Little Pony Friendship Is Magic belongs to Hasbro and their respective owners.