Equestria lost experiment(Mlp Eg x male autistic reader)

Back in Equestria long ago. Humans and Pony were living together in harmony. But in the human people there was a scientist who saw the magic of poney's for the worst. As a weapon. So buy using human science and poney magic she created a being. An homonculus fueled by the power of the magic. But instead of receiving love. The being received hate and pain. One day the being snapped and killed his creator. He then unleashed his magic over the world. It was such a catastroph that pincess Celestia and Luna were obligated to ally to queen Chrysalis, Cozy Glow, Lord Tirek and even King Sumbra to try to stop him. But unfrotunately it wasn't enought. Only the intervention of Discord was able to stop him but this costed his teeth and a part of his powers he could never have back. The being was sealed in another dimension where he was chained supposed to be stuck here forever. After this event the humans and the poney's started to argue about who's fault it was for this destrcution and the humans decided to move into a new dimesnion. A thousand years later the story got lost in time as in Canterlot High when the element of harmony was stole and used to destroy the world the binds between the human and the dimension the being was sealed became thin enought for him to broke free. He then appear in the human world and beated Demon shimmer without any effort