DELTARUNE c5+ D.I.G.I.R.?
I'm starting a trend: "DiGiR?" or "Did i Get it Right?"
I will list the theories i subscribe to (or even came up with myself) no matter how big or small they are with links to better descriptions of them if i have them, and once chapter 5 comes out i'll come back here and see how well i did in terms of my guesses. feel free to give this idea a try mewrself and reblog and tag mine if mew want!
General Theories
The Angel represents escapism and total and unhealthy suspension of disbelief. (Player Angel, also)
Deltarune will have a Chapter 0 or a playable section of game that takes place before the events of Chapter 1.
At some point in Deltarune, a Lightner will give up their SOUL (or whatever makes a Lightner a Lightner) to a Darkner, and we'll find out what object a former Lightner becomes, as well as what happens when a Darkner is able to come to the Light World. This exchange may have already occurred by this point in the story.
The Sword Board Movement Sequence (Up Up Left Right Right Down Right) will show up again.
The Pointed Tail is the mouse cursor in some way or another.
Asgore meets Ralsei and spends a decent amount of time pretending that he is actually Asriel, even though he's well aware this isn't the case.
Gaster is the window used to play the game (not just deltarune, but also UNDERTALE). He may or may not be a Darkner. He is simply, in one way or another, the screen we use to see and interact with the game. This could also mean that Gaster is the "LORD OF SCREENS" who is "CLEAVED RED BY BLADE". (I call this theory "Window Display Gaster")
The Prophecy as seen in Chapter 4 is "meaningless" in that any possible outcome that is accurately described by the Prophecy Panels is a valid outcome. In other words, any situation that can be described by The Prophecy is a valid interpretation, even if it changes depending on player choices or even from moment to moment.
We will be made to play through the entire game again, but everything is slightly different, re-contextualized, or changed by our knowledge of what occurs in a later chapter, or a previous version of a late chapter. The gameplay between a repeat chapter and a non-repeat chapter will be different in some tangible way.
There is a missing part of The Prophecy we have yet to see (and may never see) that implies that the Second Hero is a monster due to Ralsei stating as much, but the actual words of The Prophecy do not strictly limit the Second Hero to being a monster. (similar to how Ralsei stated the First Hero was a human)
The reason why "... need... soul... Without... soul... Kris... will..." is the same reason why the narration describes our body moving on its own when Kris acts without our input, which is the same reason why "THE FIRST HERO" is the "CAGE, WITH HUMAN SOUL AND PARTS!": Our wonderful creation at the start of the game is supposed to be the first hero, and whoever is on the phone is desperate to put Kris in that position and believes that getting Kris the Soul is all it takes to do so. In spite of that, we were never supposed to control Kris, which is why their actions are referred to as our body moving on its own. The Soul never registers Kris's speech for us to read: our wonderful creation was only ever supposed to talk when we told it to, so there was no point in "adding" that feature.
The Dragon Blazers Theory Set
Each different interpretation of the prophecy (i.e. Lord of the Hammer, the Prophecy Panels, the Scripture, Dragon Blazers, etc.) are or represent a specific character's view of the prophecy.
Cyber world is the second dark world that Noelle has been to, she doesn't remember the first one/time
The first and third dark world that Noelle goes to are the same dark world, a dark world in the same physical location, and/or both contain an "Ice Palace".
Alternatively to the previous point, "Ice Palace" is to "Dragon Blazers" what "Dark World" is to "deltarune". In other words, "Ice Palace" simply means "Dark World" when it comes to Dragon Blazers's interpretation of The Prophecy.
Ex-Human Dess Theories
Dess made a "deal" and gave her SOUL to a Darkner, and now becomes an object in the Light World where the Darkner she gave it to is able to exist in the Light World.
The Knight is the Darkner that took Dess's SOUL. No one is presently aware of this. This Darkner is pretending to be Dess to Kris and Carol, and is guiding them to open Dark Fountains (and start The Roaring) under the guise of "finding my original body", i.e. the Darkner that Dess became after losing her SOUL.
The Unused Dialogue within the source code is Dess's experience as a Darkner in the Light World, she's currently an object rather than a Lightner.
"LOVE FINDS ITS WAY TO THE GIRL" refers to Dess regaining a SOUL (as a result, Dess is the Second Hero). This may or may not be her original SOUL (it could be Kris's).
Any of the above theories in this section but with non-human/monster Dess if anything confirms that this can be done with a monster SOUL or some other part of a monster.