The Knight and Ralsei
Currently, I'm only focused on two mysteries in Deltarune. I don't care if Asriel or Papyrus appear in the last chapter (even though the thought is cool), I don't care where the next Dark World will be, I don't even want to consider the implications of how the Weird Route might end after this ending. I only have TWO mysteries that I'm desperately begging for answers to: What the heck are The Knight and Ralsei?
(This might be a bit long, as it's a mix of a rant and a genuine attempt to piece together an incomplete puzzle.)
We've known since chapter 3 (chapter 2 in Ralsei's case) that they aren't normal Darkners. Hell, some of us even doubt if they REALLY are Darkners, considering they almost completely break the logic and rules that other Darkners and Lightners follow.
Lightners are humans and monsters that live in the Light World, the supposed 'real world' according to Ralsei, where living beings exist and live normally. They are not affected by the Dark Fountains unless The Roaring occurs or they fall into a Dark World. If a Lightner enters the Dark World, they may undergo a minor transformation, but the most they gain is a cool outfit and weapon and the ability to use magic, perhaps gaining some superhuman abilities due to the Dark Worlds behaving similarly to a video game. Darkners are objects that come to life once a Dark World is created, and therefore are linked to their world's Dark Fountain and the work they are doing to continue living. If they are far from their Dark Fountains and/or can no longer do their work, they begin to petrify until they become complete statues. Dark Worlds made in the same place, but by two people with different mindsets, create different Darkners, and there's a good chance the Darkners from the first world won't manifest in the second and vice versa. So far, the only Dark Fountain where everyone can live together is the one in Castle Town, supposedly because it's made of 'pure darkness,' whatever that means, but it implies that the others aren't completely pure.
But Ralsei and The Knight don't follow that logic. Ralsei can appear wherever he wants, in any Dark Fountain he's in, and can stay there as long as necessary without risk. The Knight can shapeshift into various forms in the Dark World in an abnormal way, something impossible if they were human or monster, and they still have a very lively physical form in the Light World, something that shouldn't happen if they were an object. Ralsei seems like something that shouldn't be possible to exist, considering Asgore and Flowery's comments about them, and we LITERALLY saw The Knight create a fountain in front of us, something only Lightners should be capable of. And the worst thing? They not only defy the logic of what a Darkner or a Lightner should be, but they both know it, they know the rules, they manage to break the rules AND STILL TRY TO STAY WITHIN THE RULES!!!
The Knights were already somewhat famous for the fact that they could perform a 'Swoop' whenever they defeated one of the heroes (except Kris), with the last hit always, ALWAYS, dealing so much damage that it causes -999 HP, regardless of how much damage they were dealing before. And their battle against Flowery implies that it's because they know the statistics, since they reduce the 9 to 0 knowing the numbers weren't real. This could mean that they purposefully keep their attack at a high enough level to be powerful, but completely overshoot when they land a fatal blow on the heroes to ensure they fall and stay on the ground.
Ralsei has demonstrated several times how much he knows about the Player, and has shown several times how he can manipulate them to their advantage. I won't even comment on the many times he explains some game functions or how he manipulates their magic menu so that their fire magic can never be used unless it's an ACT, or how he basically kicks us out of Kris's sights to talk to them privately; that would make everything longer than it already is, but I will comment on a few things. He can cross the game's barriers. He did this once in one of the scenes after Spamton, and now he clearly did it when he helps Kris/us get past the spikes that he knows act as a barrier. Susie can get past the spikes because she follows the real-life logic 'If I don't step on them, they won't hurt me'; Ralsei does this while pulling Kris, following the logic 'If I get past the barrier while holding Kris, they can get past too because it would be the equivalent of a cutscene for them'. He also made it very clear that if he wanted to, he could not only force puzzles to solve themselves, but he also implied that the reason he has the stats he has is because he decided not to change any attributes. For all we know, we could have had a Buff Ralsei who could solve any puzzle with a simple kick, a cool animation, and an explosion, but he chooses not to. Because that's not in the rules.
And that's the thing: They both know the rules of this world, and can bend them to their will, and yet, they prefer to follow them as much as their naturally rule-breaking essences allow. And to this day, the only ones who seem to have a similar level of control to them are Gerson and Flowery. That is, a Lightner who died and returned as a Darkner, hence his contradictory nature which could help him understand and use the rules of that world to his advantage, and a flower, something that is neither Lightner nor Darkner but a strange middle ground, hence his great knowledge of the rules to the point of molding them as he wished.
Considering that the First Dark Fountain was apparently already active before the whole thing with Dess and Asgore and That Day, I wonder if it was The Knight who created it and was already active at that time. Considering that Ralsei seemed genuinely confused about it and commented that he thought The Knight and The Heroes should appear around the same time, I wonder if perhaps something else created the First Dark Fountain and ended up giving life to The Knight to fulfill the prophecy or something like that. Considering Flowery's numerous lines insinuating that Ralsei is something that is 'the impossibility himself', I wonder if Ralsei must be something similar to what The Knight is, made 'of the same stuff' or something like that. Considering how often Ralsei is strict with the rules around their and does their best to follow them, I wonder if he would actually be able to go to the Light World, but forces himself not to because something very bad would happen, either with their ability to stay in any Dark World or if he did, it would end up accelerating The Roaring.
I'm really curious to know more about them, but unfortunately, for now, this is all we have. Theories, and an absolute certainty that whatever Ralsei and The Knight are, it's something that doesn't follow the rules of the world they exist in, despite their attempts to follow it.
