The entire Mane 6 is transported back in time and have to live their. They eventually become the physical elements of Harmony to stop Discord. Luna's real name is Lulamoon.

Anyone know the fic I'm talking about?

1947921 Que sera, sera

1947921 Que, Sera sera
Here's a link to it.

1947928>>1947958

thank you both for the quick response

1948113 Not a problem, it's a wonderful story. Although I would love a follow up to this story. It would be interesting to see Celestia informing the families of the main 6 of what has happened. Especially seeing her tell Luna who their mother is. To see Celestia tell Twilight's parents, Shining Armor, and Cadence about Twilight. And to reveal to them that she is their grand-daughter and niece, respectively.

1948626
Spoiler free version
Or a happy route where the (plot device) are reverted back to there original states

Spoiler version
Where the elements revert back to the mane six like a stasis pod, and story wise it could make sense, i mean past twilight drawing on the power of an alicorn through her element

Dear god I love that story one of the few ones to ever actually get me to cry.

"I know, so beautiful."