I would have changed a few things based on my own personal preference.

Presentation: Toss out all the tags except Tragedy, because that is what 90% of the story was about. All those other tags were just off-putting and confusing.

The point of the story: I felt it missed out on the point it was making (if it had any). Yes, the ponies found out that they were actually some nice changelings. That's very tragic, but would it have made any difference if they had known that beforehand? They would have defended themselves from an attack regardless.

Maybe they would have taken this Changeling prisoner, if they had known, and that would have been a good point to make.

It was a good tragedy, but it needed a tiny bit more for me to upvote it.