Can Equestria handle the impact caused by Wild Pony, who is actually the somewhat scrambled and ponified martial arts prodigy and weirdness magnet otherwise known as Ranma Saotome?

Set after the failed wedding at the end of Ranma ½ and approximately three years before the return of Nightmare Moon, then rapidly skips ahead to just a few months prior.

Now has a side story: My Little Sphinx

On a side note, like MLP:FiM itself, the story will mainly be Slice of Life, with the occasional sections of Action/Adventure popping up now and then. I mention this because I couldn't choose both tags, and of the two, this story weighs in more on the Slice of Life side.