My Little Pony XXIX: The Spoilers have been DOUBLED!

[Deadly]

I haven't read Esper's 'fics yet (I need to, eventually), but could Starswirl the Bearded be the original author of the book that is rather important to the storyline?

And puns? We should know by now to leaf well enough alone.

Well, "amniomorphic" would most likely suggest some transformation of the womb or fetus, rather than genderbending a grown pony which is what's done in that story. Still, if Starswirl fathered one foalbirth-related spell, why not others? So, I say yes, he'd make an obvious author of said book, but I'll leave that up to Esper, of course