*Have you thought about a world where everything is exactly the same...
*Except you don't exist?

This AU has no further presence online than this page.

For information to establish this AU's online presence, see the Template AU Page.
* Do you wanna have a bad time?

To meet the UTAU wiki's article standards, this article requires a standard Infobox. Please help by improving the article.

To see the standards for {{Infobox AU}}, click here.

* Umm... H-hey, I couldn't see a thing!

* This article would benefit from the addition of an image.

* B-but it's okay!

* You can upload a picture to this article by going to the Upload page and selecting the file you wish to add to the wiki. Images that are of the .JPG format cannot be uploaded, and the file must have a proper name to be admitted.

This AU is the first of a What if? series, following what could happen if someone else led monster kind.

A long time ago, Asgore ruled the Underground, like usual. However, Chara didn't fall down until much later, so he never started the anti-human policy. Gaster got tired of him not doing anything to free monster kind, overthrew him, and locked him inside his own castle after moving the path leading to the barrier. Eventually, the power got to Gaster's head, and now he rules like a tyrant.


Undertale characters


Toriel is the garbage cleaner of the new capital NEO Home. She's not allowed to leave the city due to the fact she's family of the former king. One of her horns partially broke off during a punishment, and wounds of dust cover her body.


Chara is the 7th fallen human, and one of the Snowdin rebellion leaders. She's the most active in combat, due to her physical strength and determination. She also faces Frisk after a genocide run.


Asriel is the son of Asgore and Toriel, and one of the Snowdin rebellion leaders. He's the mastermind of the organisation, and rarely fights himself since Gaster's constantly on the lookout for him. He's a lot older than in Undertale due to never dying. He trains Frisk, and never lowers their HP to 0, like Papyrus.


Muffet is the Snowdin rebellion's third in command. She was forced to lower her prices so much she could not make any profit, and got caught when trying to sell illegal lower quality products containing all kinds of junk. She has a different goal than Asriel and Chara, and tries to take Frisk's soul to either give it to Gaster in order to gain his trust and get her old life back, or destroy him if he refuses. She is also good at working with different kinds of poison after some training from Chara and Asriel.

Canine Unit

The dogs serve under Gaster to destroy any rebellion in Snowdin, but actually support them and in exchange for playtime and food help them hiding themselves for Gaster's inspections.

River Person

When his business got forbidden due to the Underground monorail system, he joined the rebellion as a spy.


Grillby isn't officially a part of the rebellion, but helped with making it so the rest of the town doesn't betray them.


Napstablook got taken away by Gaster to forcefully fuse with a robotic body to serve in his army. One day he managed to destroy his control chip and flee to Snowdin, but got almost completely destroyed by his own cousin Mad Dummy during the attempt. Now he's stuck in an improvised life support machine inside Sans' old basement.

Annoying Dog

The annoying dog now is a part of the Snowdin rebellion, but this doesn't change anything about his behavior.

Mad Dummy

Mad Dummy is the commander of the Waterfall section of the guard, and is very dedicated to his job, going so far to nearly kill his own cousin. He's not a fan of Gaster though. He just likes to stab people that don't listen to him with his knife.


Gerson is Mad Dummy's underling, and is forced to look out for rebellion. His age made him to weak to properly fight though, and Mad Dummy considers putting him on the list for Amalgamation, wich is the fate of people that are useless in Gaster's eyes.


The Temmies are forced to work in the Tem Flake factory that's build on their own home, which modifies them into a drug that stimulates obedience. Any Temmie that gets Hoives is executed as a possible threat to monster kinds safety. Thinking about college and their rich history is punished with torture.


Undyne was forced into an experiment which overflowed her with Determination in order to make her the ultimate weapon, but melted her instead. She now functions like an Amalgamate, and attacks Frisk immediately if she sees them. She often gets angry and attacks something or someone for no reason. She can't be killed in any route.


Papyrus was accepted into the guard and now has to keep an eye on Undyne. In an attack of Undyne, he was severely injured and many of his body parts had to be replaced by robotic weapon systems. He's now very afraid of her, and regrets his life decisions. When defeated in Neutral and Pacifist, he escapes to Hotland to report it to Gaster, and receives an upgrade from Sans to be able to defeat Frisk. When the player attempts to kill Papyrus in the first battle, Undyne blocks the otherwise fatal blow.


Sans is Gaster's first assistant. After the melting of Undyne and the Amalgamates, Gaster decided to test a low dose on him. This melted a part of his face, and sometimes he starts acting on impulses like an Amalgamate. Usually he's just Sans though, except he doesn't make puns, since Gaster threatened to pull out his eye if he made one more. After the experiment, his strength increased as well.


Alphys is Gaster's second assistant. She's harshly injured from a punishment for a past mistake, and is now locked up in a room in the True Lab to watch over the Amalgamates. In Genocide, Gaster almost kills her when she suggests evacuating everyone, before Sans manages to convince him.


Mettaton is the commander of the Hotland security guard. Despite hating his job and the control chip inside his body, he did everything Gaster told him to do and was rewarded with new upgrades and a new position. However, one single mistake, and he'll be downgraded to his first form. When first encountered, he is completely under Gaster's control.

Securitypants (Burgerpants)

Securitypants is the security guard of the CORE entrance.

Gaster Followers

Gaster's mysterious assistants. Not much is known about them, aside from the fact that they live in the CORE.


Gaster is cold, calculating and cruel. He does not care about anyone but himself. He does everything possible to break the barrier, with the goal of enslaving humankind. He doesn't look like the usual Gaster design, and instead has a white labcoat and glasses. Cannot be spared in any way, but in True Pacifist, he is captured by the rebellion.


Red is New Home's guard commander, and is tasked with guarding the old castle. She is secretly a member of the rebellion, and is Asgore's only contact with the outside world. Acts mean to him if Gaster's around.


Asgore is weakened from his imprisonment, and all his flowers withered away. He almost gave up all hope for monster kind's future, but Red's company helped him survive.

Dead characters

Monster Kid. Died in a experiment where Determination was injected directly into his soul. His soul still remains unshattered, but his body and consiousness melted away completely.

Ruins Dummy

Was killed by his cousin when refusing to serve in Gaster's army.

Jerry. Got executed after being a jerk to Gaster. Noone cared.

Bratty and Catty. Got executed after getting caught while trying to get into the Snowdin rebellion. This lead to the capture of Nice Cream Guy.

Shyren. Got executed after Praise Gaster day since he hated her singing performance.

Shyren's agent. Got executed for assisting Shyren on Praise Gaster day.

Nice Cream Guy. Got executed after getting caught doing activities for the rebellion.

All Whimsuns. Died when their homes got destroyed for the new city.

So Sorry. Got executed for existing at one of Gaster's more sadistic days.

Onionsan and Woshua. Died of Waterfall's pollution.

All Ice Caps. Gaster took their hats and used them cool down the CORE in one of his more sadistic days.

Bob and Tem Shopkeeper. Died after testing a highly experimental Tem Flake recipe. Recovered from it though.

Rock. Got pulverized when refusing to move away when NEO Home got constructed.

Half of Muffet's spiders. The spiders she couldn't take with her were all slaughtered after her escape.

Added characters


The result of an experiment where Gaster separated his postive emotions from himself, wich caused him to become the tyrant he is now. He has all the positive parts, and is very kind. He's the only one that doesn't get tortured by Gaster, as he's afraid his death would kill him, wich is untrue. Takes Flowey's and Toriel's role as guide trough NEO Home. Wears Sans' jacket and Papyrus' scarf.


A bunch of flowers brought to life the same way as Flowey. The dust of executed monsters is used to create a private army. The reason they listen to him is a device that'll pump weedkiller in them if they refuse to do his bidding. Due to the big amount of them, none of them have control over the timelines before Frisk fell down.


Undertale locations


The Ruins are completely different, since Gaster turned them into the new capital NEO Home. While the city has no security guard of it's own, it's full of camera's and can be quickly reached by the guard of any other region. Contains much more houses, and the area vaguely resembles the CORE.


Snowdin is the secret headquarter of the rebellion. They have multiple bases spread troughout the area, these being Sans and Papyrus' old seemingly abandoned house, wich is their main headquarter, due to the 2 hidden rooms below it, Papyrus' old cage, Grillby's, wich is their unofficial meeting point, and the Annoying Dog room.


Waterfall is very polluted and toxic gasses float trough the air, caused by the Tem Flake factory. Mad Dummy filled it with traps, and Undyne's rage bursts destroyed many structures. Temmie Village is gone.


Hotland is the second city of the Underground, after he made everyone abandon New Home. Most monsters here ae very poor, and their houses are very unstable. The lab also expanded massively, and Mettaton Resort is the center of the police department.


The CORE is Gaster's castle, and his own private lab.

New Home

New Home is crumbling down after it's abandonment, and only the castle is in a good state. The Judgement Hall is still the place where Frisk gets judged, but in neutral and pacifist, the road to the final challlenge against Gaster is somewhere else.

New Locations

Underground Monorail System

A high-speed train replacing the river, since Gaster thought River Person's boat wasn't fast enough, and it didn't connect to NEO Home, unlike the monorail.

Tem Flake Factory

A factory where Temmies are enslaved to produce Tem Flake drugs.

Misc changes

  • Omega Flowey and Asriel God of Hyperdeath are nonexistent.
  • Gaster is the final boss of the True Pacifist and Neutral routes.