What if the 10th Doctor regenerated into a pony?

Just like probably every Doctor Whooves story on this site, except it's Who not Whooves. The Doctor crashes in Equestria and has to find out why.

Never really had time for friends until that one faithful day that she showed up, then my whole world went upside down (In a good way).

A brony in Equestria, no memories, yet he is destined for greatness from the start.