After having her parents violently taken from her, Twilight Sparkle, succumbed to unknown magic and influence, turned her back on harmony and declared war on existence itself, until the combined power of the princesses, the remaining elements of harmony and the pain of a broken heart finally crushed her power in half and sealed her soul into the Moon, while isolating the dark influence far away, in the frozen north.
Now, after twenty years since her banishment, the tides of fate have turned once again, as the tainted, primordial magic known as hatred finally shatters her bonds. A Crimson Dawn emerges, ready to devour the very life of the world."
Disclaimer: I DID NOT WRITE THIS, Femto DID.
He deleted his story while ago and he didn't have the chapters anymore on his computer, but I did so I requested him if I could upload Hour of Twilight on account so everypony out there who liked/loved the story can read it once again! I got only up to chapter 14 and I will release a chapter every two days.
His own words in private message (proof): Femto: Alright, you have my permission to upload it, finish it, continue it, do whatever you like with it. But Silverghost and Crimson Dawn are 'copyrighted' XD