Get nosey with Celestia? Check. Marry Celestia? Check check. Run and defend a prosperous country, be a Prince, lead millions in wisdom and might, and not commit a huge social faux pas in high society? Gonna have to get back to you on that.
Ponyville, Equestria. Fallow Meadows, Indiana. Two towns torn from thier worlds and deposited together on a third. Can Human and Pony work together? They'd better hope so, because they're not alone...
A human soul is stuffed into King Sombra's body. Having no idea what's going on, and thinking he is in some kind of coma, he just casually strolls into the Crystal Empire.
Right before the Elements struck, the Nightmare unleashed a spell out of desperation. A substitution spell. Otherwise known as the correct use of Kawarimi.
Nightmare Moon banished Celestia, only to be defeated by Ahuizotl. Ponykind were made the scapegoats to blame for her scourge. 1000 years they pray for a saviour to deliver them. Anypony will do. Enter the last hope, a pizza delivery dude.