Sudden Changes

170 reviews
Content rating
Everyone
10K+
Downloads
Content rating
Everyone
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About this game

This is a completely free to play fan-made unofficial project based on the original Undertale™ game created by Toby Fox.
All rights, characters, and assets belong to their respective owners.
This game is a fan work that is not affiliated with Toby Fox or the official Undertale team.
For any copyright inquiries or asset removal requests, please contact me directly at kywoo0130@gmail.com. I respect intellectual property and am fully committed to resolving the issues!

* Undertale By Toby Fox
* Created By xiaoQ
* Android Port By Ilka
* Released By KYwoo

This game is about the Sans boss fight in Sudden Changes.

The Story:
【NO AU】Sudden Changes is a role swap following the basic rules of Storyshift with only the lost souls, along with Mettaton, Napstablook, Chara and Asriel changing positions.
Welcome to Sudden Changes! An UT AU where Sans got a GUN!
Updated on
Jul 13, 2026

Data safety

Safety starts with understanding how developers collect and share your data. Data privacy and security practices may vary based on your use, region, and age. The developer provided this information and may update it over time.
  • No data shared with third parties
    Learn more about how developers declare sharing
  • No data collected
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Ratings and reviews

157 reviews
Debra Burks
July 16, 2026
this game is good but it has the lack of options like switching the joystick and buttons l was hoping if you could also add debug mode for those who struggle at some of the hard parts of the game
2 people found this review helpful
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JJ NoName
May 20, 2026
I think there should be joystick and more options but the bones sans uses are to op there stronger than blasters there way to op making attack 3 extremely hard due to the bones doing a quarter of your hp being in the bones for a quarter of a second edit: I found out why in normal sans fights being in one bone doesn't make other bones do damage so let's say there's 2 bones really close together instead of getting damage from 1 bone like normal you get hit by both making you just die in a instant
2 people found this review helpful
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Oliver
November 9, 2025
The fight itself is good, but the QoL is awful. There's no way to configure anything. Wanna play in English? Nope, gotta translate Chinese. Wanna control yourself with one hand? Nope, gotta use both in a way that makes no sense. And lastly, there's no way to change the difficulty like you can in any of KYwoo's other apps, leaving it nothing but painful to play in few faults by the player.
3 people found this review helpful
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What’s new

Latest Release of Sudden Changes! SANS HAVE A GUN!