Fire Emblem: Keys of Truth was a Fire Emblem fanfiction, featuring an AU of the Future Past DLC from Fire Emblem: Awakening crossovering with Fire Emblem Fates. It used to be found on Fanfiction.net, but has since been deleted.
Twenty years have passed since Lucina had performed the Awakening and dealt the final blow against Grima. Since then, she and her friends have been hard at work, rebuilding Ylisse from the verge of humanity's destruction. Since then, they have married and started their own families. But this fragile peace is threatened when Princess Soleil, the daughter of Lucina and Inigo, discovers a girl named Kanna who can transform into a dragon. And then Kanna's buried memories about her blood family begins surfacing...
Examples:
- All Just a Dream: The story opens up with Kanna dreaming about the Ylissean royals and her brothers and cousins demanding to choose a side, much like in Fates.
- Alternate Universe: The Fates kids come from a world where the Fates' Generation 1 had failed to reach Valla in time and they intended to try again when the Bottomless Canyon opened up but... Anankos found them.
- Always Someone Better: Siegbert continues to put Xander on a pedestal, probably even more so since Xander died when he was six.
- Ascended Extra: So far, Lilith is more involved in the plot than in Fates.
- Badass Family: The exalted family, which probably is half of the Awakening cast, along with the Hoshido and Nohr royal cousins, along with Kanna and Shigure. They all end up being combined anyways, through several of the ships.
- Battle Couple: All of the kids' ships are developed by fighting together, as in Awakening and Fates, but Soleil and Kanna especially stand out.
- Big Damn Heroes: Ophelia, Mercutio, and Eleanor all pull this off during the chapter where they rescue Luna.
- Birthmark of Destiny: The exalted brand, as in Awakening. So far, only Aurora, Celio, and Luna's brands' locations have been revealed.
- Blonde, Brunette, Redhead: The spouses of the first gen Hoshido royals. Scarlet and Elise have blonde hair, Kaden has brown hair, and Tsubaki is a redhead.
- Bodyguard Crush: Olivier is one of Luna's retainers and they end up together.
- Break the Cutie: Poor Luna...
- Childhood Friend Romance: All of the Awakening kids' parents have this, along with some of the kids. The Awakening second gen ships are: Inigo/Lucina, Owain/Severa, Marc/Noire, Yarne/Morgan, Gerome/Cynthia, Brady/Nah, and Laurent/Kjelle.
- Climax Boss: King Phairdon, the bastard son of Gangrel.
- Cool Sword: Falchion, Yato, Raijinto, Siegfried...
- Embarrassing Nickname: Siegbert is sometimes called Sieggy by his cousins.
- Family Theme Naming: Inigo and Lucina's children all have a heavenly connotation to their names. Soleil is "sun", Altair is a star, Aurora refers to aurora borealis, Celio means "sky", and Luna is "moon".
- Marc and Noire's kids all have a name that start with an A.
- Owain and Severa's children all have Shakespearean names.
- Gerome and Cynthia's two children, Royse and Olivier, have a plant theme. Royse means "rose" and Olivier is derived from "olive".
- Generation Xerox:
- Soleil ends up falling in love with Kanna, who has a connection to a dark dragon god. Soleil's maternal grandmother is Robin.
- Royse and Olivier are the grandchildren of Cherche, who was Virion's retainer. Royse serves Celio, Virion's grandson, and Olivier serves Luna, Virion's granddaughter.
- Asugi's parents are Saizo and Kagero and they served Ryoma. Now he's the personal retainer of Shiro, Ryoma's son.
- Midori mentions this to Kanna, when she states that she and Dwyer wish to serve her, because their fathers served Corrin.
- Half-Identical Twins: Chrom and Robin's twin children, Marc and Morgan.
- Happily Adopted: Kanna was adopted by a farmer couple. This doesn't end well.
- Heel–Face Brainwashing: Both Shigure and Kyo get hit with this early on, causing them to side with Plegia.
- The High Queen: Lucina, even though her title is technically exalt.
- Hot-Blooded: Soleil, as an inheritance from Chrom.
- Interspecies Romance: Kinu and Velour are the results of one, and Rayon is the son of one. Ironically, Rayon and Kinu end up together.
- Irony: It has been commented that the Nohrian siblings look more alike than the Hoshidan siblings who are full siblings. The Hoshidan cousins all have some kind of blonde hair, save for Matoi, who inherited Sakura's hair. Meanwhile, Siegbert and Kisaragi are blond, while Eponine has Camilla's lavender hair and Laurel has pink hair from Felicia.
- Keet: Olivier and Kisaragi are both this.
- Kissing Cousins:
- Shigure is engaged to Matoi, who is the daughter of Sakura, making them step-cousins.
- Corrin and Azura, though it's revealed in this fic, they're only adopted cousins.
- This is poked fun at with Altair, who finds his second cousin, Mercutio, attractive.
- Like Father, Like Son: Most of the Fates children have the same class as their canonical parents.
- Massive Numbered Siblings:
- Lucina and Inigo have five children and Lucina ends up getting pregnant again some time after the attack on the castle.
- This is explored in Kisaragi and Siegbert's support, as Kisaragi wishes to learn more about his Nohrian heritage.
- My Sister Is Off-Limits: Shigure is rather... protective of Kanna, and isn't pleased that Soleil, who is the same age as him, is interested in her. Never mind that Kanna likes Soleil back.
- Red Oni, Blue Oni: Shiro is the red, Siegbert is the blue.
- Sibling Yin-Yang: The most prominent example is Altair and Aurora, Lucina and Inigo's twin children. Altair is easygoing and flirtatious, while Aurora is serious and studious.
- Take Up My Sword: Well, swords in Siegbert, Shiro, and Kanna's cases. For Laurel, it's Leo's tome and for Kisaragi, it's Takumi's bow.
- Taking the Bullet: At Lucina's attempted assassination, Soleil pushes Lucina out of the way of a falling boulder.
- Would Hurt a Child: Soleil was nearly killed by Risen when she was four years old, all while trying to protect her two year old sister to boot. Soleil also states that she, Altair, and Aurora probably would have been killed if her parents hadn't returned to the castle in time.
