All that Twilight Sparkle wanted was to be closer to her brother.  This little quest of hers leads to a much larger one as she learns the dark, hidden secrets of the Mind Merging spell from Star Swirl the Bearded himself.  This single spell and how it is used could easily decide the fate of all of Equestria and, indeed, the rest of the world.

I had a story.  It was a great story.  Then Twilight Sparkle decided to go ruin that.  Why did she have to hear me?  Why couldn't she just assume she was going crazy like any other pony would have?

Wait, I'm getting ahead of myself.  I, the mighty writer of this very story, was narrating as usual when Twilight Sparkle happened to hear me.  Now, it would be in bad storytelling form to spoil what happens next, but suffice to say, hilarity ensues.

Twilight Sparkle is bothered by the state of the world.  Not a single pony is concerned with anything but themselves.  If she ruled, things would be different.  Equestria needed change, so she would make it happen herself.

Castlevania: the home of the fearsome Count Dracula.  It is full of perhaps the darkest, most terrifying creatures ever to walk the planet.

Apparently Rarity frequents the place for gemstones.

What if Discord had defeated Twilight Sparkle and her friends?  What if he was unimpeded in his neverending search for chaos and disorder?  What if he ruled Equestria?  How will the Mane 6 cope?

WHO CARES?  It's not supposed to make sense!  This story is all about Discord and the crazy chaos he oh-so-loves to spread!  Watch as he makes Equestria his own.  There will be many laughs to be had!