Set on January 8th, 1988.The Main seven are teleported to one of the history's last stands when they go through the mirror for studying the Human world, but things take a turn for the worse.
I'm thinking on doing another one but maybe in Stalingrad, if this story goes well and this is my first story (Inspired by the story Battle of Agincourt by  dominatusimperator) and edited by Cerber

In the wake of the interrupted wedding of Princess Cadence and Shining Armor, the Royal Guard went on a changeling hunt, fanning out throughout Equestria to find any changelings living amongst ponykind. The captured changelings have been confined to a guard barracks in Canterlot.

Meanwhile Princess Celestia is finding herself swamped with petitions from ponies across Equestria asking for amnesty for their changeling friends, colleagues, and lovers. Princess Luna, who has been itching to regain some responsibility since her return, offers to take on the petitioners... and the changelings.

(sex tag for off-screen births and hinted baby-making)

One day the world took a turn for the insane. Earth and Equestria connected and now humans and ponies live together in harmony. Bronies are now a widespread culture and everyone is happy because of it. Everyone except me the only sane person alive. I know that this isn't right and I know that maybe one day humanity will wake up. They will see how stupid they've made the world and what they let into their hearts. One day I'll finally feel like I'm not an outsider. One day ponies and all pony sympathizers will perish in a violent spectacular marvel.

This story is a sequel to Steel Solstice

Continued in: My Little Apprentice: Apogee

Twilight Sparkle learns that the trust and goodwill of the Princess isn't always a good thing as she's given the trust of an important assignment. When that assignment turns out to be long-term, how will she handle taking care of a filly of her own? How will she handle this strange new filly, who proves to be much more than she appears. As a matter of fact, she seems to be from an entirely separate universe.

Meanwhile, Second Chance has kept only enough of her memories to know that she isn't what she should be. The wonderful world of Equestria has its own dangers, and she seems to have a knack for attracting trouble. The more of her memories return, the more she wishes she could just forget. But you can't forget when all of Equestria depends on you remembering.

Only one thing's for sure: The longer Twilight keeps this strange filly in her care, the stranger her own life will become, and things she thought she knew about Equestria will unravel before her eyes. Strange ancient devices, an eccentric mint unicorn and her so-called "Equestrian Precursor Society" are only the beginning for Twilight Sparkle as she begins a journey of her own. She too may wish she could simply forget. Unfortunately, it's too late for either of them.