Undertalecrossover Stories

30 Stories

Sans-sational Venture in Tensura  by DontAskImN0body
#1
Sans-sational Venture in Tensura by ImN0body
Sans was sick of the endless resets that haunt his world, knowing full well that is the player's fault. As repeating cycle continues something odd happens at yet another...
Judgment of the Demigods: Demigod Karma by xxx_Crescent_xxx
#2
Judgment of the Demigods: Demigod...by Crescent
This is a crossover between Percy Jackson and Undertale After a genocide route, Sans is somehow not dead, and Chara has broken the barrier and mysteriously disappeared...
Completed
👎︎♏︎♋︎⧫︎♒︎ ♋︎■︎♎︎ ⬥︎♓︎■︎♑︎♎︎♓︎■︎♑︎⬧︎ by Firehedgehog
#3
👎︎♏︎♋︎⧫︎♒︎ ♋︎■︎♎︎ ⬥︎♓︎■︎♑︎♎︎♓︎■︎♑...by Firehedgehog
Harry Potter was master of death, he was use to ending in other universes/timelines. This time he ended up as a skeleton monster Remake of Death and wingdings om ao3 201...
Society's Contrive [BNHA X Undertale]  by DontAskImN0body
#4
Society's Contrive [BNHA X Underta...by ImN0body
Life itself is unfair. People are lost in the blissful deception, believing everyone is treated the same. But there are those who got it worse, Sans learned that the har...
Universe Tale by Jaybird_Dragon2021
#5
Universe Taleby }Dunked_on_24/7{
Remember when Chara killed Sans? What happened if instead of him dying, Gaster pulled him into a different dimension and was able to heal them with a healing pink founta...
Undertale x Mixels stuff by CandyLovely148
#6
Undertale x Mixels stuffby CandyLovely148
Here is all the stuff for my new Undertale & Deltarune AUS, Mixeltale & Taxlimel (which is an anagram of Mixeltale). I do not own Mixels, Undertale, or Deltarune in any...
Into the Darkness ‖ GF X UT by StarFallerXD
#7
Into the Darkness ‖ GF X UTby much regrets™
While exploring Mount Ebott(which was one of the mountains that surrounded Gravity Falls), the Mystery Twins Dipper and Mabel accidentally fell into a huge pit, which le...
The multiverse (Book 1) (+me and @Krystal_GlitchGirl) by Kitty_catpup
#8
The multiverse (Book 1) (+me and @...by Kitty_catpup
Book cover created by @Krystal_GlitchGirl A collab book series with @Krystal_GlitchGirl This book series will be about the aphmau smp meeting different fandoms, I'll be...
Here we are by lizzyAfton0634
#9
Here we areby lizzyAfton0634
Undertale x Ninjago This is not my original idea, it was a one shot, that is on fanfic.net. It is under the same name. There's a lot Nya didn't tell the ninja about wh...
klee meets undertale ; ᵃ ᵘⁿᵈᵉʳᵗᵃˡᵉ ᵃⁿᵈ ᵍᵉⁿˢʰⁱⁿ ⁱᵐᵖᵃᶜᵗ ᶜʳᵒˢˢᵒᵛᵉʳ ( ◠ ·◠)ა by ryshuko
#10
klee meets undertale ; ᵃ ᵘⁿᵈᵉʳᵗᵃˡᵉ...by ryshuko
♡ : 𝘯𝘢𝘵𝘴𝘶𝘬𝘢𝘴𝘩𝘪𝘪 - 𝘢 𝘸𝘰𝘳𝘥 𝘶𝘴𝘦𝘥 𝘸𝘩𝘦𝘯 𝘴𝘰𝘮𝘦𝘵𝘩𝘪𝘯𝘨 𝘦𝘷𝘰𝘬𝘦𝘴 𝘢 𝘧𝘰𝘯𝘥 𝘮𝘦𝘮𝘰𝘳𝘺 𝘧𝘳𝘰𝘮 𝘺𝘰𝘶𝘳 𝘱𝘢𝘴𝘵. ... 𝘣𝘶𝘵 𝘯𝘢𝘵𝘴𝘶...
Universe Tale Future by Jaybird_Dragon2021
#11
Universe Tale Futureby }Dunked_on_24/7{
Everything sure has changed for the better, not only has all the gems been uncorrupted and the war with the diamond authority has been dismissed but now, all monsterkind...
My Hero...Verse?//MHAxUnderverse Crossover// by Cosintany
#12
My Hero...Verse?//MHAxUnderverse C...by Cosintany
Seconds before disaster, and the end of all AUs, Ink managed to grab the Perseverance Vial. Quickly, before his enemies managed to snatch it from him again, he unleashed...
Max and the Monsters- a crappy Undertale fic by MaxwellJacksWrites
#13
Max and the Monsters- a crappy Und...by MaxwellJacksWrites
I started this while bored during the FSA, and my friends wanted me to upload it. I know it's cringy, I don't really care, lord help him.
Fallen Countries by AlyChng123
#14
Fallen Countriesby MARSHYCAT
Art ain't mine.I only used it to make le cover.Countryhumans highschool, elemantary and kindergarten au all mashup together cos why not?Other than that this was mosty ma...
How Bea Afton met the CreepyPastas... by BeaTheFanGirl06
#15
How Bea Afton met the CreepyPastas...by BeaAprilGirl
Hi 👋🏻! I'm Bea. This is my crazy story about my friends, who are known as the CreepyPastas. I have a few other friends besides them, buuut let's focus on the CreepyPas...
Louds In Pun-derland by Cantthinkofonr
#16
Louds In Pun-derlandby ThatOneGuyAtHome
One camping trip gone wrong and here they are. Who would've thought that Mt. Ebott is actually in Michigan and it so happens to be in Grand Venture State Park with the g...
The Misadventures of Sans Undertale by SadManMcGee
#18
The Misadventures of Sans Undertaleby SadManMcGee
Sans Undertale goes on wacky misadventures throughout the known multiverse.