Equestria is a land of magic and mystery and ponies. They have a vast and rich history and secrets of all kinds, some good and some bad. One legend was of the SinEater... Lost to all but a few raggedy tomes, the legend of the SinEater told of a being chosen from a race not known to any of Equestria.
And now, the SinEater has been brought to Equestria, with no memories and instructions from an engimatic pony. His path crosses with those of the Elements of Harmony and the cataclysm of a great change is on the horizon.