After a thousand years in exile, an ancient prince and elder brother to the royal sisters returns, along with the comrades he fought side by side with 2000 years ago. But it seems with his return, the enemies of Equestria have returned as well, along with an even darker threat that threatens to change the ways of the world forever. Now that he's returned, his comrades must band together alongside the student of princess Celestia, the sister that he blamed for sealing away their youngest sister out of greed. But alongside this young unicorn student, he will adventure through the path she has now chosen, the path of friendship and harmony. He will protect her, and fight this threat alongside her, as she embraces her destiny, and tries to fight against this evil for Equestria's future.
Ponies all across Equestria have sought the help of the princess-goddess sisters who rule them. Time dictates whether one princess or two was available to aid them, and if one was ever held in favor over the other.
Princess Celestia has dedicated her life to helping every good pony.
But there are always ponies who cannot be helped.
Original version: https://www.fimfiction.net/story/396330/forever-mare
TW// Suicide, gender dysphoria, homelessness, miscarriage, mentioned rejection, and very bad magic