Adult Content Warning

This work could have adult content. If you continue, you have agreed that you are willing to see such content.

• Yes, Continue
• No, Go Back

If you accept cookies from our site and you choose "Yes, Continue", you will not be asked again during this session (that is, until you close your browser). If you log in you can store your preference and never be asked again.

1. Dualtale AU: Two sides of truth by ED_Soul

   Fandoms: Undertale (Video Game), Underverse (webcomic)  

   • Mature
   • Creator Chose Not To Use Archive Warnings
   • Gen
   • Work in Progress

   29 Dec 2025

   Tags

   • Creator Chose Not To Use Archive Warnings
   • Monster Kid (Undertale)
   • Asgore Dreemurr
   • Toriel (Undertale)
   • Mettaton (Undertale)
   • Papyrus (Undertale)
   • Frisk (Undertale)
   • Undyne (Undertale)
   • Alphys (Undertale)
   • Grillby (Undertale)
   • Napstablook (Undertale)
   • Original Undertale Character(s)
   • Sans (Undertale)
   • Underverse (webcomic) - Character
   • Dualtale AU
   • Underverse (Webcomic) - Freeform
   • Nightmare Sans - Freeform
   • Alina Kaiser (Original Character)
   • Alternate Universe - Canon Divergence
   • Faked Death
   • Mourning
   • Grief
   • Funeral
   • Aftermath
   • Revenge
   • Grieving Frisk
   • Manipulative Gaster
   • Guilty Toriel
   • hidden identity
   • Dark
   • Plot Driven
   • Angst
   • Emotional Manipulation
   • Xtale Sans | Cross (Undertale)
   • Something New Sans | Killer (Undertale)
   • ink sans - Freeform
   • Dreamtale Sans | Dream (Undertale)
   • Slow Build
   • Multiverse
   • Alternate Universe
   • Hope and Despire
   • X-Gaster - Freeform
   • Pat Hicks (Original Character)
   • Equil (Original Character)

   Summary

   Description:
   This story is based on the distant and little-known Dualtale AU,where nothing is as simple as it seems. In this world, unlike the original Undertale, monsters were never trapped underground. But what was the price for peace between humans and monsters? And how is it connected to XGaster, when these events unfolded long before the X-Event?
   (Features characters from Underverse and Undertale,adapted for this story.)

   Author's Note:
   In the Dualtale AU,the famous rule "Kill or Be Killed" is replaced by another:
   "Speak out, and you will be silenced."
   This is a universe built on lies and dark secrets that everyone holds.Every character has their own agenda and their own rules and it's better not to try and learn them.

   Series

   • Part 1 of Dualtale AU: Two sides of truth

   Language:

   English

   Words:

   32,123

   Chapters:

   19/?

   Comments:

   9

   Kudos:

   3

   Hits:

   165