Undertaleaus Stories

1.2K Stories

Mama Nootmare (A fanfic with the bad sanses) by Ravenpoint
#1
Mama Nootmare (A fanfic with the b...by Ancient Failure
A fanfic/story of Nightmare and children bad guys! All of the bad guys are children excluding Nightmare and Error. This is a story of Nightmare being a parent. I am ter...
An Interesting Reincarnation (Reader reborn as...) by AliceParadoxi
#2
An Interesting Reincarnation (Read...by AliceParadoxi
You wake up, finding yourself standing in a desolate grassy field, only the green grass had withered and died, leaving behind a dry, lifeless expanse. Above, the sky was...
Our Pen by R3myR3ad3r
#3
Our Penby R3myR3ad3r
You're the Ink of your multiverse, and you don't even know it. Well, until you meet the Ink of another, along with Error. -NOTES- I made the cover! This obviously isn't...
Out-Code Spawns in a different Multiverse (SCP Foundation x Alphatale) by adamabyss12
#4
Out-Code Spawns in a different Mul...by adamabyss12
There are 2 different multiverses that are next to each other. One that is made simply of Code and Data, being made by the Game Creators, used for entertainment by the P...
Threads of Balance  by Moonlight_Malaysia
#5
Threads of Balance by Moonlight_Malaysia
A young person wakes up in the endless Void, transported into the glitching, destructive body of Error Sans. With the power to erase entire timelines at a flick of his s...
My Anomaly (An Error Sans X Reader)  by nightmare597
#6
My Anomaly (An Error Sans X Reader...by Nightmare
When your sibling Chara goes missing you fear the worst, but life takes a surprising turn for the better when they release the monsters trapped underground. Living this...
Naturetale : reborn as lavender  by KarmaAkabane425
#7
Naturetale : reborn as lavender by Karma Akabane
(As far as I know, no one has made a story about naturetale like this so..and the only reason why I writing one like this is because of fatal error part 5? Or part 4, go...
Reincarnated as Dream with Differences by Xalatea_Zennia
#8
Reincarnated as Dream with Differe...by Zennia
(Discontinued) A random teenager dies, and no they don't get hit by the Isekai truck unfortunately. The 'driver' couldn't make it on time. This teenager wasn't really r...
In this world, it is Consume...or Be Starved and Consumed (Axetale Aliza x OC) by adamabyss12
#9
In this world, it is Consume...or...by adamabyss12
The Underground...once the home of the race of Monsters, now having turned into an infectious wasteland of starving-infected beasts, with the monsters horribly twisted a...
He Came to Stay (Blue x Bad Guys) by EmberAshTheFaithful
#10
He Came to Stay (Blue x Bad Guys)by EmberAshTheFaithful
Living on a steady diet of caffeine, sugar, and sheer will is not a healthy lifestyle. But how else can you keep up with teammates that need no sleep, no food, and who e...
~ Sans AUs x Reader OneShots ~ by AvocadoDragon
#11
~ Sans AUs x Reader OneShots ~by 🥑🐉
(Book gets better with each OneShot-) Requests are (Closed ❌), Thank you! I've started this when I was in 8th grade, because I've seen a few x Reader books and was like...
As ready as I can be since I'm dust...wait hold the phone! Pregnant!?  by KarmaAkabane425
#12
As ready as I can be since I'm dus...by Karma Akabane
(You know how it goes, someone from our world Ends up dead and becomes dust sans..but somehow pregangt, different things, different personalities etc
New Purpose (US!Papyrus x Female!Reader) by OreoDaSkeleton
#13
New Purpose (US!Papyrus x Female!R...by ~Oreo~
Y/N, meets a new coworker that changes her life forever. A monster, doing his best to make a living after moving out of the underground. Sans is this ecstatic, cheerful...
To Kill A Killer by RosesHaveThorns16
#14
To Kill A Killerby Rose Aurum
Nightmare's gang always knew that their job was risky, but they never expected to actually die. Then Killer was killed. Nightmare found a replacement quickly enough, bu...
Darkness Is Nicer Than It Seems (Nightmare Sans x Reader) by Lollipopswirl99
#15
Darkness Is Nicer Than It Seems (N...by Lollipopswirl99
(Y/N) had a regular life. A normal job, home, everything. Sure she had her own problems like insomnia, nightmares, and no friends but that wasn't anything to special. T...
Sanscest Pics~ by OnlyAiko
#16
Sanscest Pics~by Aiko but Stupid
Okay I'm only doing my Favourite ships so I won't be any taking requests. I stand my ground and would like it To stay that Way for as long as I stay on this App. ⚠️ALSO...
Jaune Error by CCKGISKMKGSRAD
#17
Jaune Errorby Core Jaune
Jaune Arc this man always wanted to be a hero like his ancestors but fate decided to mock the blond knight Jaune saved Cardin Winchester from the Ursa Major but Cardin d...
Completed
Perspective by Fandom_Glitch
#18
Perspectiveby Off-Track
Try seeing things from another point of view... Fresh wants to feed off of a long lasting host, he wants to exist longer. How will he do this and how will he survive? On...
Completed
The Teenage Guild To Reincarnation by oO_GOLDRUSH_Oo
#19
The Teenage Guild To Reincarnationby ☆GOLDRUSH☆
Never did you picture yourself in this situation. Sure, you dabbled in the Undertale fandom and it's AU's, and you knew basic things about the more popular ones, but her...
Reborn as Error by Kiwi_Seal
#20
Reborn as Errorby Kiwi_Seal
Cover image made by me. Someone meets their end too soon and meets someone who gives them another chance to live a more fulfilling life. One that they would enjoy despit...