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1. The Omnipotent Demon by TheBellflowerWitch

   Fandoms: Fire Emblem: Fuukasetsugetsu | Fire Emblem: Three Houses, Ben 10 Series  

   • Mature
   • No Archive Warnings Apply
   • F/F, F/M
   • Work in Progress

   08 Apr 2026

   Tags

   • No Archive Warnings Apply
   • Edelgard von Hresvelg/My Unit | Byleth
   • Bernadetta von Varley/Hubert von Vestra
   • My Unit | Byleth
   • Edelgard von Hresvelg
   • Dimitri Alexandre Blaiddyd
   • Claude von Riegan
   • Jeralt Reus Eisner
   • Caspar von Bergliez
   • Hubert von Vestra
   • Bernadetta von Varley
   • Dorothea Arnault
   • Linhardt von Hevring
   • Petra Macneary
   • Ferdinand von Aegir
   • Azmuth (Ben 10 Series)
   • Self-Indulgent
   • Crimson Flower | Black Eagles Route (Fire Emblem: Three Houses)
   • rated mature to be safe
   • My Unit | Byleth Has Emotions
   • Byleth has the Ultimatrix
   • Fire Emblem: Three Houses Spoilers

   Summary

   Byleth Eisner was always know as the Ashen Demon . A mercenary who was feared all over Fódlan for how they showed no emotions while coldly cutting foes down. Now, a chance encounter with three youths and a strange mystical gauntlet from the skies has changed Byleth into something more, something Omnipotent. How will Fódlan deal with the changes this new Byleth brings forth? And more importantly, how will Byleth herself deal with the changes both good and bad these strange new powers will bring her?

   Language:

   English

   Words:

   302,041

   Chapters:

   18/?

   Comments:

   54

   Kudos:

   93

   Bookmarks:

   35

   Hits:

   7,279