Discord is now reformed but the Mane Six never needed to lift a hoof after their first confrontation with him so what made him change and, more importantly, why is he roaming free around Equestria at night when no one's awake?

That's right this is the story to what it was that caused Discord to change without the need of the Mane Six...well at least without ALL six of them ready to turn him to stone with the Elements of Harmony.