new au idea js popped into my head :]
So Noelle commits a suicide pact with Kris in-the Weird Route during chapter 5, and the two are implied to have drowned in the lake.
Now, I saw a theory that the flowers have already been in a dark world, as did Asgore, due to his mention of another fountain Now, This theory also had Carol be in that dark fountain/world, and thats why she has a sword collection
ANYWAY enough backstory here's the au barebones: basically Toriel, Carol and Susie enter a natural dark world in the lake to find Noelle and Kris, without Ralsei or any other help.
Susie came back after Kris and Noelle do their Suicide Pact thing, and panics after not finding them. She runs to find Ralsei, but crashes into Toriel, who makes her explain. She takes Susie to Carol's office, and though it takes a lot of back and forth, she gets Susie to explain. Carol asks Toriel to leave, and makes Susie explain the dark world stuff, and she resolves to solve what happened by barring the lake and deciding to investigate herself. She takes Susie with her, but Toriel asks to join as it's her child too (Kris).
Even though there is no fountain, there is a dark world because of the thing that they are created by anti-light and the eyes filling that in. So they try to get to the bottom of the lake, and succeed (WITHOUT DROWNING) and begin their search. Susie is confused about no Ralsei, but obviously he can't be there because no fountain.
The dark world is a strange, warped waterland, covered in deep mist. It's... cold. It's so cold. There's dark stone all over the walls, covered in wet patches of algae and mould. It's... so cold.
Yet the three push on. They have to find Kris and Noelle. They have to. They keep going, until a pair of familiar figures show up. It looks like Kris and Noelle, facing the mist away from the trio. Susie reaches out a hand to Kris' shoulder-
Their face is contorted, stretched with anguish, their eyes covered by wet streaks of dark hair. They cling to Noelle, who turns around with a similar expression. They are both covered in algae, mould, and their faces were sunken in. Something was wrong. Something was seriously wrong.
But... they have to fight them. Don't they..?
(Feel free to ask questions about this au!!)