To share my thoughts on the knight.
I feel like the knight didn’t create the first dark fountain. Not exactly. It’s existed in the shelter from either before dess disappeared, or at the moment she did.
The children followed the pointed tail — Kris and dess, or maybe even Kris, dess, Asriel and Noelle, and maybe even Catti, since apparently she had tried to summon a demon with Kris
The pointed tail, perhaps most likely friend(but interestingly, what if it was catti?), led them to the forest, to the shelter. Where they maybe tried to summon the “demon” like mentioned a few times/implied, and something went wrong, and catti ran away as mentioned. Perhaps the fountain could’ve been created here, as a part of the summoning ritual? Maybe that scared her off?
Something happens, and dess gets stuck in the dark world. Asgore somehow gets to the scene, and sees enough to later understand that what had happened was a dark fountain. The rest of the gang manages out but dess is left behind in the shelter, and it’s closed.
I don’t have concrete evidence just vibes, but I feel like a lightener cant survive in a DW for such a long time. I think the darkness corroded dess or something, leaving her body to turn into whatever the knight is. Something something “you’ll see her once, then move on” could also be a hint to the fact once they see dess once and recognize the knight as her, they’ll understand nothing can be done but move on. She can’t be saved anymore.
Or Maybe her soul and body separated somehow, her soul getting stuck in the code of the game while her body turns into the knight.
Ahh so many thoughts and theories this lq makes no sense . Big fan of how in the WR Noelle and Kris are implied to have gone past the lake, through the ground maybe even, into a new place. We get to skip a whole chapter, and move onto the second half of chapter 7, because we’re going straight into the shelter. Chapter 6 is probably the holiday house, chapter 7 the shelter.
Then thinking about the whole deltarune is gasters creation theory, I’m a big fan of it. Huge huge fan of how people theorize that he created a dark world in undertale and fell in. It’s so strongly implied it’s something similar.
God I can’t wait to find out what the true answer is. I feel like so many ends are going to be tied up, things we’ve been wondering since when undertale came out. Things I’ve grown up pondering. It’s going to be monumental for a whole generation I’m so excited