Omegatale is an AU created by LunaIzMeh on December 2016.

W. I. P. (Work in Progress) This might look messy, since I don't know how to do coding and stuff. If you want to help, you can ask me in the comments.

I am really sorry if this AU offends or triggers anyone. I am also planning on making this a book on Wattpad, so beware for spoilers.


A long time ago, monsters lived in the surface with humans.

Both races lived in peace and harmony, until the monsters started to gain more determination.

Scared of the potential monsters had in destroying the human race, the humans declared war on the monsters.

After months, years, and decades of war, the humans were victorious.

The humans decided to cast the monsters underground.

A well-known warlock among the humans volunteered to create a barrier between the humans and monsters.

And thus, a new realm was born.

However, not everything lasts forever...

In this AU, each realm has a certain amount of determination it can handle before it collapses. The limit in determination is based on the creator of the realm, in this case the warlock. The warlock had a lot of determination, so he made the underground's cavern itself require a lot of determination. This way, monsters will only be able to have a small amount of determination.

But centuries later, the descendants of the warlock started disappearing. The warlock and his descendants were the only ones who could regulate the determination of the underground, so after they started disappearing, the Underground and it's inhabitants started to lose determination. This causes the entire realm of the Underground to gradually die.


  • Ask in my profile's message wall if you want to join the AU. Any request in the comments will be ignored.
  • If your OC doesn't have a page, I will think about it, considering my rules and the Wikia rules. If you don't make a page in a month, though, I will make your OC a minor character until you make a page.
  • If I don't reply right away, please be patient. I have many things preventing me from using my gadgets (SCHOOL WHY), so please wait and DON'T SPAM.
  • If you have any edits you want to add to the page, please just ask me in my wall. Just tell me the thing you want to edit, and I will edit the page as soon as I can.
  • Absolutely NO sexual themes or gore. Scratches, injuries, and disorders are fine, as long as it's not too major. I'm trying to keep this AU PG-13 at the most.
  • No OP and/or 4th-wall breaking characters, since it could ruin other people's experience.
  • No blood/romantic relationships with canon characters. I'm sorry, but this could conflict with other users and lead to a fight, or worse.
  • Character info (for people without character pages) should consist of HP, ATK, DEF, Area, Lost Determination, gender, powers, race, Major or Minor, and appearance. Follow the Wikia's OC rules for the info.


The Ruins

The Ruins are in a very bad condition. The walls, plaques, and pillars have crumbled down and are partly demolished. Paint is peeling off the Ruins' walls. The red leaves are now brown and crusty, and the golden flowers Frisk falls on are wilted, since the flowers aren't taken care of. Even Toriel's home is breaking down, dust, cobwebs, and crusty leaves in and out of the house.


Snowdin still maintains it's name, despite the condition it is in. The snow in the area is melting, and the trees in Snowdin forest have collapsed. Some of the houses in Snowdin Town has been vacant for a long time, and are broken and messy. The Librarby's and Grillby's' signs are barely hanging, The Librarby's books being scattered on the floor and Grillby's being filled with gloomy people looking for an escape to sadness. The "Welcome to Snowdin Town" sign is broken, and one of it's legs have collapsed.


Like Snowdin, the Waterfalls still maintains it's name despite how it currently is. The only things falling down are small trickles of water, as all of the holes connecting the Waterfalls to the Surface has been almost completely blocked by debris. Almost all of the echo flowers have lost their petals and have wilted, and they only make small whispers of some parts of the things they hear. The few echo flowers that are intact have been sent to Hotlands for cloning, some determined monsters attempting to make them bloom again.


The Hotlands, too, retains it's name, even though it's not as hot as it was before. All of the lava in the area has cooled down, and the heat vents work very rarely. The lab is smaller, and the true lab has dead goops of what were amalgamates. Only some of the amalgamates have kept their determination and continued to live. The DT extraction machine is one of the only things in the entire Underground that is still intact. The MTT resort is almost empty, except a few monsters.


The CORE doesn't have it's power working very well. The Ice Wolf throws ice less frequently, making the power shut down sometimes. The pipes and walls on the core are being naturally chipped off, and the nodes are the only parts of the area completely intact.

New Home

New Home still maintains it's monochrome color scheme. The flowers in Asgore's home and castle have wilted, only a few of them surviving. Asgore's home is in similar condition to Toriel's, but not as bad.


Canon Characters


Flowey is the only canon character that wasn't affected by the Determination drain, since he doesn't have a soul that could have it's DT drained out of. He is fully composed of soley Determination, so the end, or Omegallia, as the monsters call it, can't get his will of anything. He was originally intended to be given a soul, but after Alphys started losing her Determination, Flowey was left in the True Lab, unfinished. He could still live, but couldn't feel any emotions. He eventually found a way to escape, and retreated to the Ruins.


Toriel is losing her Determination to protect and preserve things. She still takes care of the human children, but will give up and attack shortly afterwards. She doesn't take care of the Ruins anymore, thinking that there is no point to it. This is the reason why the area is very broken.


Sans is losing the determination to keep his sanity, but tries to keep what is left of him. He acts like everything is okay when other people are around, but will go mad when alone. He usually goes to Grillby's as a form of escape, like all of the other people who go there.


Papyrus is losing the determination to stay positive and optimistic. He is developing symptoms of depression, but tries to believe in his brother, Sans, not knowing that he is in the verge of insanity. Papyrus uses his remaining determination to try looking at the bright side of things, but often fails.


Undyne is losing the determination to protect and free others, and thus becomes more and more selfish. Aside from Flowey, Undyne is the canon character with the most determination. She is slowly losing her grip, but tries to think of the people that needs her help or has helped her, mostly Asgore, Papyrus, and Alphys.


Alphys is losing the Determination to stay alive, but is still holding on. She is sending the determinations from the amalgamates and the human souls to the CORE in times of emergency. She is hanging on by thinking of the things she hasn't confessed yet, and believes that she shouldn't let the secrets die with her.

These are all of the characters I have for now. As I said earlier, this is a WIP.


  • This AU was inspired by Omega Flowey's name. I was thinking about random stuff at class, and the word "Omega", which is a Greek Letter and a word meaning "The End", came to my mind while I was thinking about the Neutral Route. And I also got some inspiration from the Bible's book of Revelations... Sorry if that offended some of you, but it's my religion. (I'm gonna get so much hate for this)
  • The Delta Rune is replaced with the Omega Rune. I'm done with the concept; I just have to do the sprite.
  • In the original concept, all of the connections to the Surface was supposed to be COMPLETELY blocked. But then I though, "How would the humans fall?"
  • All of the Warlock's descendants have a soul of pure Determination. (Hint, hint)
  • I made some concept art for my OCs, but STILL didn't make any for the canon characters.


Creator of the AU: Me, LunaIzMeh

Inspiration: The original Undertale, Revelations of the bible (As mentioned earlier)

Support: My friends. One of them has a Wikia account, and they go by Skaitleen03.

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