There's something important about SOULs and Determination to the plot of Deltarune - which may be evidence for Kris being the Vessel
One aspect of Deltarune that has not been discussed very often yet among the comunity is one of Undertale's main lore elements - Determination as a substance that provides SOULs with much of their power. I believe this theme is once again going to be an integral plot element within the game.
1. A quick recap of how Determination and SOULs work in Undertale
Determination is mentioned nearly everywhere in Undertale - it's mentioned in flavour text every time the player saves the game. This makes sense - it's vital to the story. The entire reason Asgore is harvesting human souls is so he can absorb them and their Determination and break the barrier between the overworld and the Underground.
We know that every soul possesses a small amount of Determination, but that human souls possess by far the most. Monster souls normally possess so little determination that they immediately shatter upon death - Boss Monsters being a notable exception.
We also know that it's possible to extract a certain amount of Determination from a given soul, as shown by the DT Extractor and the existence of the Amalgamates, the byproduct of an experiment conducted by Alphys into rejuvenating Monsters who had Fallen Down by injecting them with Determination extracted from human souls. Alphys figured out how to do this via the help of a series of 'weird tapes' described in ENTRY NUMBER 5. It is unknown who made these 'weird tapes', but it's widely presumed to have been Gaster due to his secretive nature and role as the former Royal Scientist. For the sake of this discussion and theory, we will be assuming that this is true as there appears to be no other possible candidate.
Regarding SOULs, there are two other important aspects that we as the player learn from our interactions with Flowey¹. A being without a soul can end up animate and alive if injected with Determination, and in their conscious state they can also absorb other SOULs - as Flowey does at the end od the Neutral and True Pacifict route.
But as we see during the Omega Flowey fight, even after death, the SOULs remain with a degree of independence and control with which they are able to influence whatever host body they find themselves in. They can act independently, even directly against the wishes of their host. Even the less powerful Monster SOULs can do this to some extent - as shown in the end of the True Pacifist route.
2. What do the people in Deltarune know about Determination and SOULs?
Yet, in spite of it's near constant mentions in Undertale, Determination is conspicuously absent from Deltarune. The word itself is only used once in the entirety of the game, when Queen states that it's necessary for one to possess Determination in order to open a Dark Fountain. In every other place it would make sense for the term to be used it's replaced with the word 'will', but 'will' is so far not nearly as defined inside the game as Determination was in Undertale.
In fact, it is not defined at all. It has no known function - it appears that when referring to one's 'will', whoever is writing about it is moreso referring to a person's individuality. It is defined strictly through it's relationship to the SOUL - defined in one of the library books as the 'culmination of one's will'. Yet it also states that 'the SOUL's true function 'remains unknown.' What's going on? In Undertale nearly everyone has at least a working grasp of how SOULs operate - but here they're a total mystery.
The answer is that all the info that we know about SOULs comes research conducted while Monsters were trapped in the Underground. The disparity in power between human and Monster SOULs was known even prior to this research due to the Human - Monster War, and so was the instable and fragile nature of Monster SOULs and bodies. But since in Deltarune there was no conflict between the two, this disparity is not known and obvious - if at all².
And since the Monsters were never pushed into the Underground, there was never a reason for anyone to develop the schematics that Alphys used to develop the DT Extractor - and as such Determination as a substance was never discovered and named⁴.
I also think this is somewhat intentional from Toby in order to mislead the playerbase. By shifting the focus away from already established lore mechanics he's able to hide certain aspects of the plot in plain sight - even when he's incredibly conspicuous about doing this , such as with normalnpc seemingly being at two places at once where he can block off access to some potentially illuminating lore text and interactions
Regardless, there is essentially no one in the narrative that knows about the existence of Determination and its' power.
Except for one person.
3. W.D. Gaster
Being the previous Royal Scientist, and a brilliant one at that, it is not surprising that Gaster could design the Determination Extraction Machine. The similarities between it and the Gaster Blasters used by Sans in the Genocide Route also suggest a strong connection between the two.
We also know that Gaster is involved in the world of Deltarune in some way. The game so far remains cryptic about the extent of his involvement, but given how blatant the narrative has been about his presence - going as far as to have him directly communicate with the player if they lose to the Knight.
Similarly, Gaster is widely assumed to be the one talking to us during the Goner Maker sequence - before telling us that 'no one can choose who they are in this world' and we start the game in Kris' body. This seems to be a double entendre - Kris has no choice but to be under our control and we have no choice but to control Kris.
But why does Kris not have this choice?
4. Whatever it is that we're in control of is not Kris's soul
Because what we think of Kris's SOUL is not actually their soul. It belongs to someone else. This is why we - through the SOUL - are able to exercise a certain level of autonomy and control over Kris's body, just like how the 6 Human SOULS are able to exercise their autonomy while part of Omega Flowey's body. Similarly, no character in the entirety of Deltarune or Undertale is shown to be able to manipulate their own SOUL in the way Kris does with 'theirs' in removing it from their body - but manipulating the SOUL of another in regards to whether it'll be part of your body or not appears to be more or less fair game.
5. But why is Kris in possession of this SOUL in the first place?
It is because Kris is the Vessel. Kris is the 'CAGE WITH HUMAN PARTS AND SOUL'. Kris is the Goner we create at the start of the game.
Kris is said to be the only one who can close the Dark Fountains. I do not think this is the case - I don't think Kris can close the Dark Fountains by themselves. Closing the Fountains requires the SOUL to go out and shine a light onto the Fountain. They are not shown of being capable of doing this without it. One of the sentences said by the mystery caller fairly explicitly says that Kris should not go into a Dark World without the SOUL - likely because they would not be able to get out if they did so.
The SOUL being a requirement to close the fountains also seems to suggest that Monsters do not in fact hold the same amount of Determination as Humans, much like how crossing the barrier in Undertale is only possible for humans or those who possess a human soul⁵ - so either a Monster, or a soulless being that has acquired the soul of another⁶.
There are also other hints that suggest that Kris is the Vessel. The very first thing the player sees when they open up Deltarune is the Goner Maker - a character creator where it seems like they're designing their own grayscale copy of a Frisk-like human being.
It's an overused bit of analysis at this point but - sigh - copies are monochrome and the Vessel's colour scheme resembles that of the Goners, who amongst other things seem to reveal themselves as either deteriorating versions or near replicas of already. But it's also said in the Chapter 4 egg room that Kris has a 'gray smudge that they can't wash off'.
The immediate response to this (as seen in SpookyDood's video on the topic that, although quite superficial, did have an influence on the writing of this theory) could be that this is happening because Kris's natural skin colour is actually gray rather than yellow, but that they were 'coloured in with care' by the love of their family which caused them to develop a healthier, yellow colour. The 'smudge they can't wash off' could represent their knowledge about their creation and identity being a permanent blight on their mental health⁷.
6. Thematic relevance
A lot of theories seem to overlook whether they would make sense not just with the established canon, but the themes that are already being discussed and developed in the plot.
Kris being the Vessel does meet this criteria because it adds another layer to their identity crisis - it's not just that they're not a Monster unlike everyone else in Hometown or their family, but they're being forced by a higher power to take on a burden and role that they don't want. Especially given that they don't seem to be able to function properly without it inside them. It's why Kris despises the SOUL so much - they need it to survive.
It also adds another layer to the theme of fighting for one's freedom and individuality. Kris is currently a kid reckoning with having a body they don't fuck with that occasionally gets possessed by a foreign entity - but if Kris were the vessel, that would mean that they had even less of a choice in the matter given that they were created primarily for this exact purpose.
It would also address the currently locked and loaded Checkhov's gun that Deltarune currently has in the form of the Vessel - which has so far been totally unused past the initial Goner Maker sequence.
For a much more in-depth piece that provides a lot of thematic analysis and evidence that doesn't revolve around trying to figure out how check out this post by Baldur: https://www.tumblr.com/kenomacreature/811530603618025472/deltarune-meta-memories-made-in-grey?source=share)
7. But if not Kris, then to whom does it belong to?
As far as I can tell, everything lines up. Except for this. This is the main thing I can't figure out.
SpookyDood opines in his video that for Kressel to work it needs for the SOUL to have been manufactured. The problem with this is that it explicitly goes against established Undertale canon - as ENTRY NUMBER TWO states: "This power cannot be recreated artifcially. SOUL power can only be extracted from what was once living." And since there don't appear to be any dead humans (not) running around, there don't seem to be any possible candidates⁸.
Quite literally the only thing I can think of is that this is somehow Frisk's SOUL that Gaster helped import from the Undertale universe, but that's stupid and the sort of thing a 13 year-old would come up with.
I'm sure Toby will cook something up regardless of whether I'm right or not - and that I'm much less likely to be wrong than I am to be right. Nevertheless it's very fun to speculate and I can't wait for chapter 5 to come out - I'm kinda salty that I didn't sit down to write this earlier.
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¹ And to an extent Mettaton and the Mad Ghost - but ghosts, despite being Monsters, appear to play by a different set of rules in regards to their bodies. Napstablook says as much if you try to kill him in Undertale.
² A lot of people, including the Wiki editors, seem to think that the fact that Monsters are able to open Dark Fountains means they have similar amounts of Determination as humans. We don't know if this is the case or if the Monsters in Deltarune just barely pass the minimum threshold required. We don't even know if the Determination referenced by Queen is Determination the substance. However, they do not seem to be able to close the fountains, unlike Kris. More on this later.
³ Similarly, there is no mention of Boss Monster SOULs being different to those of regular Monsters.
⁴ ENTRY NUMBER FIVE shows that it was Alphys who made this discovery and gave it the name we know it as.
⁵ There are a few more parallels between the Dark Worlds and the Underground which are worth analysing.
⁶ Flowey being the other example of this - howecer it must be noted that even though Flowey is soulless, he is not a Goner. These appear to be two different types of creatures within the canon.
⁷ I have a sort of crack theory that Kris is actually in the process of becoming a Goner again and reverting back to their original form due to them keeping their soul outside of their body for so long. We know from Flowey that this can happen as he's unable to maintain his form as Asriel for very long after he lets go of all the trapped SOULs, and he can't maintain Omega Flowey without the human SOULs either. We also know that soulless creatures are generally very weak - and soulless Kris walks with a stammer, is unable to speak clearly or in a raised voice and in general does not appear to be very eloquent, similar to how Jockington and the weird bird in the library appear to be becomig Goners based on their declining speech patterns. However this is a huge stretch at best and a massive leap at worst because we currently don't know shit about how Goners function - and I suspect it'll remain a mystery forever.
⁸ Is it not suspicious that the only human we've ever seen or even heard mentions of is Kris?













