DELTARUNE / Revised Multiversal Theory 

"Sans becoming a God is an extremely valid option." -Jaru 22/7/2022

I had a Deltarune thought about W.D. Gaster Gaster is generally thought to be the person who talks to us in the goner creation at the start of Deltarune, one thing that’s bothered me is that they speak in Wingdings so how come they are speaking normally in Deltarune? Well that’s fairly simple, Gaster was shattered across time and space, not split across it. So if Gaster was shattered that would imply unevenly or with differing segments. Think of breaking a mirror, it isn’t a whole bunch of identical shards, some are far larger. Gaster in Undertale was either only a small fraction or somet to do with their identity, perhaps a part of their hands. In Deltarune Gaster speaks fluently so perhaps the part shattered to Deltarune was the mouth And in the real world Gaster runs a survey (Deltarune) so perhaps a fragment of say his brain was sent here, Toby Fox helped Gaster speak to the public to help with this experiment for some reason. Other parts of Gaster fall into other realities and in varying sizes so say in the reality of dnd not enough landed for them to be able to manifest themselves Does that make sense?

The man gives so much attentions and efforts into his theories that he goes back and corrects/reworks the old ones when needed. How can you not love this channel?

the multiverse can best be described as: "For every world you didn't, there's a world you did." my guy you were right this entire time, the problem is, there's no difference between an alternate timeline or and alternate reality because alternate timelines are what make up the multiverse which form the alternate realities.

Also, remember meeting Sans in deltarune in the first chapter and there was a dialogue option to say. “ hey sans, how’s it going?” And Sans reply’s “ good, but that’s weird considering I’ve never met you before” and then winks. He also says he’s from out of town. Could this sans also be from another timeline?

You actually work like a scientist. You always rely on evidence and data to arrive at the most logical conclusion, and can even recognize when you think you were wrong. Just an amazing channel, thank you so much for making videos.

I like the idea of Parallel Realities as a concept. It feels like a large scale evolution of the idea of Convergent Evolution in speculative zoology. For people who don't know Convergent Evolution is the idea that different species in similar groups could potentially fill the needs when some species die out. The most well known example is in After Man where in a future where animals like deers, wolves, and whales all die out other animals evolve to fill their needs. (In this case Rabbits filled the deers slot, weaseles and rats filled out the wolves, and penguins filled out the whales). I'm not a good explainer but I found it funny how similar these ideas were in concept. Amazing video!

Ever since chapter 2 was released I've always thought that the ending of Deltarune would be an apocalypse, something where everyone dies, and nothing matters. Otherwise, there's no way there's only one ending if you can choose to kill relevant characters. And I guess your reset theory could also work for that. HOWEVER, does that count as one ending? It doesn't really end there, it just goes back to the beginning. So, what if there is the reset "ending", and an actual ending where you defeat the Angel? Maybe one where you get all the shadow crystals and secret boss weapons? I only find one problem with this theory. When you die in chapter one, it says: "IT APPEARS YOU HAVE REACHED AN END.", so if there is only one ending, then it is always that one, where you are defeated and the world is covered in darkness? Anyways, I hope we can have the two endings thing, but who knows. Knowing Toby, even with only one ending he'll make something great.

Seeing Jaru obsess over fanart is really heartwarming

It’s nice to see you understanding the parts where you may have gone wrong, it’s a pivotal part of improving as a theorist or even just as a creator in general I know some people are sometimes pretty rude about where you went wrong (hell, I probably was at some points since I am in agreement that some things you say do seem like a logical leap) but I’m sure that they have good intentions! And if not, then well, as I said, it’s still good to understand where you go wrong!

8:55 i think that the bad handwriting line not only alludes to alphys' involvement but is also an on-the-nose pun to further hint at the wingdings' hand symbols.

Probably, Determination cannot fully erase someone's memory because of them also having determination, yes, in lower quantities, but some at least, and thus, others determination "overpowers" some of ours, and make imposible to fully erase their memories. Doing a true reset, we use Asriel powers, 7 human souls, which is enough to completely erase their memory

you know, hearing this theory made me think of the line of the goner kid from undertale and made me wonder how it might relate if this theory is correct: "Have you ever thought of a world where everything is exactly the same... Except you don't exist? Everything functions perfectly without you... Ha, ha... The thought terrifies me."

As someone with a hyper-fixation on this game, your theories are very interesting to hear about and discuss! Keep up the good work! :D.

this channel never fails to amaze me! i love how in depth everything is, and i am so glad you’re able to revise your theories and make changes!

I think your theory videos are some of the most well put together - or the greatest evidence of brainrot, depending on the mood of the day - but I do want to disagree on one point. While I love engaging in these diegetic explorations of how the lore fits together, I think it’s a bit rash to say that Toby making the connection between Undertale and Deltarune merely a superficial coincidence would be a mark against him. In fact, I personally consider that the most likely answer. Toby loves being one step ahead of the player, setting them up to feel like they’ve bested him only to be brought down by the realization that he anticipated them in everything they did. Perhaps there is some actual in universe explanation for the connection between these two games, but I don’t think Toby will ever reveal it. I’m sure he knows it, but it’s far more fun to lead players in circles, chasing an answer just always out of reach. That’s literally what W.D. Gaster is, a carrot on a stick. None of this is to imply that there isn’t value in these theories, I think there’s a lot in them. But I also think Toby’s meta narratives warrant a smidge of defending.

hey man, i just wanna say how much i appreciate your videos. i have been looking for someone that gives extremely blunt theories with lengthy explanations on deltarune for a while, and your theories itch that part of my brain that has been desperate for it! i keep your videos on as a podcast of sorts, they’re extremely entertaining, keep up the good work dude!

2:13 - why are we able to reshape reality to previous state, but we can't use that power to shape that reality to anything else? Being able to travel back in time with determination seems simplier that being able to reshape whole reality to our will but it can only be to our previous safe point and can't be anything else.

Your FanArt is ALWAYS sick! :D Those artists are Killing it

Love how you build up your theories then in the middle of the video add a bombshell revelation like "its oberson smog" or "its parallel realities". It gets me every time and im all here for it. Appreciate the content!

Always love to see a new Jaru theory release. They're always so insightful and well made. Keep up the good work!

I absolutely love your theories, and I look forward to every single video. As always, this was a great one.

your amazing videos never fail to bring happiness to my day and you saved me at my lowest point so for that i can never thank you enough. it's clear how much effort and thought goes into each and every video you make. this video alone just proves why your channel is the best on the app. there's just something inherently special about the content. your morbid theories presented with such enthusiasm is so refreshing, and you are always so passionate about your work and theories and you aren't afraid to admit when things don't quite add up, PLUS you acknowledged the holes in the theory and patched them! kudos to you jaru for being the perfect theorist and creator 💜

It's always a good day when Jaru uploads. Anyway, I think this interpretation of the multiverse is the least flawed, but I still think Deltarune is an Alternate Timeline. I think the UT Timeline can't be reached by the Angel because a lot more Determination was used to split the timelines into UT and DR that what Flowey or the Angel have. Also, what Sans was saying could be remembering faint memories of the Angel.

its very wholesome you as a content creator actively out of your way showing artwork in your videos and praising it this will actively motivate those artists who look up to you and make them willing to go forward very kind

Man your undertale/deltarune theories are great! They're so detailed and well thought.

I do want to point out that as far as we know from in-game mechanics and events, DT can only change timelines within one's own lifetime. You cannot, for example, load a timeline where Chara never died. Because Chara died long before Frisk was around to use DT. It thus stands to reason that, if Sans is from an alternate timeline that branched long before he was born, he wouldn't be able to use DT to go to that different timeline. It simply wouldn't be possible

Quickly becoming my favourite channel on here, I get excited every time I see a new video and here that “hello”

I love this man’s videos he is honestly probably the only reason I have a RU-vid account anymore, another great video, as always

hi jaru ur videos are a lifesaver to me right now i’m hyperfixated on this stuff and your long form videos provide so much entertainment and distraction thank u so much

I just wanted to say thank you for all of your time and effort in every single one of your videos. This channel is always entertaining, interesting and calming to watch. I appreciate how you showcase people's fan art as well, it really shows how much you care about this community and your viewers. Keep doing what you're doing!! :D

the amount of effort you put into your videos is INSANE man keep up the good work

Two things (sry i have only watched this video so idk how these things were adressed previously): - Sans's room easter egg when he does the legendary fart master joke. The door has a rainbow smoke below like those in chapter 1 used to travel in the dark world. Also papyrus says when he enters the room that sans is pranking frisk across time and space. Who else is affected by "across time and space"? Gaster!!! And gaster has entry 17 who clearly depicts how a dark world behaves when opened like the closed, making photon readings negative!! (darkening the screen). - *Also something shocking is about clam girl's dialogue.* She states that "suzy" might be the reason Frisk/Chara or the player is "here", but where is "here"? shortly before the release of deltarune clam girl turns into a goner (black and white lost gaster followers). It might be that the reason Frisk or the player is in undertale is because of the events in Deltarune. (next up my theories and questions) But if im up to speculation and theory crafting, maybe not the player themselves, but the SOUL. Mabe Kris's soul, since its stated that Chara died, their determination infused into flowey, but where is the soul of them if its supposed to stay like the others? If that kind of death meant that chara's soul was shatered, and frisk had fallen into the underground, why was Frisk chosen as a vessel? what if the vessel making game in deltarune made Frisk in the first place? *or maybe if deltarune has different rules, if its a human soul from deltarune, it means it can shatter?* After all, if deltarune monsters bleed, who is to say that humans have monster traits and shatters when the human dies. Or maybe, undertale itself is a dark world? And toby is pranking us because after all, undertale has tale in a name, so maybe its a dark world opened in a story book about the deltarune. Would also make sense because save and loading is aviable only in dark worlds on deltarune. I can say gaster had a hand in this save load feature, and maybe the player too, since Deltarune appears to be made because gaster invited the player in. Whatever he did, maybe gaster from undertale did the experiment to save and load, but as a monster he is weak in determination so he scattered like that, and because save and load is a videogame term, it called in a player to fill that power or something. IDk. im really confused, and there is a lack of answers.

Now I need some sort of “End Game” sorta collaboration where every Undertale/Deltarune AU comes together to battle the Angel

Excellent, another theory video. I'll put my reading on pause for now to watch the video.

When Jaru uploads, you know it is going to be a good day. Love your theories man, keep up the great work!

I was literally just watching your another video. Keep up the good job, mate!

I always enjoy your theories, your voice is so nice to listen to. I also love how much you appreciate the fan arts and the community. You're definitely one of the best Undertale/Deltarune content creators. Keep up the great work and as always stay determined!

I've just about finished bingeing all your Deltarune theories, and after your Sans video I can't wait for you to make a Gaster video! Especially love that artwork at 18:31 too!

I really love your videos! Always an exciting day when a new one gets dropped. I know you probably have lots that you're working on, and this would take a long time to do, but I'd love to see a chapter 2 lore playthrough from you! I really enjoyed your chapter 1.

Neat analysis video! Thanks for uploading!

I've been binging these videos and i realized im not subscribed yet, Here you go my friend. You deserve it

So one thing about your theory that the monsters in deltarune have physical bodies. When your making your vessel at the beginning of the game, you have the option to chose its blood type. You can choose A, AB, C and, D. The thing is the blood types C and D don’t actually exist. Why wouldn’t they know this if they themselves have blood? Edit: now that i think about it, I can safely say that gaster is the one making the vessel. My reasoning for this comes from multiple pieces of evidence. 1) many people have theorized that the deltarune universe is an experiment created by gaster. This is proven by entry 17. Darker yet darker, photon readings negative ( witch means he would looking at something made of pure darkness like a black hole (or a dark fountain perhaps) and this next experiment will be very, very interesting ( something that has been mentioned many times regarding deltarune by Toby Fox) 2) one of the gaster followers said he fell into his own creation. Maybe he doesn’t mean the magma core but the deltarune universe. 3) the reason the creator of the vessel would not be familiar with blood is because he has a magical body and is from a universe were he has no experience with blood. However there’s one major hole with this theory: gaster has been shattered across time and space. But I think I have one thing to explain this, the shadow crystals. The shattered remains of gaster. Shards of forbidden knowledge that drive people crazy. Knowledge like alternate universe and timelines or that their reality is just a game. Maybe our goal is to collect them all to reassemble gaster. What do you all think?

I really wish youtube would notify me when these are posted, hit the bell and still doesn't do anything, great videos man, love your theories

when you mentioned parallel realities i half expected you to pull out the super mario 64 file select theme lmao "but first, we need to talk about parallel universes"

Got to say a little proud of myself since I did mention the idea of parellels universes in your original timeline video.

glad to see you've revised the theory so it picks up on distinctions laid out in a few spots across the UT/DR multiverse- i remember watching the original video and feeling that something was Wrong with the conclusion that undertale and deltarune belong to the same universe, even if what sans says about timelines isn't what came to mind for me. if you're curious, susie's "everyone bleeds" line sort of tipped me off, though it really has more to do with the fact that i see monsters in deltarune as being much less literal than monsters in undertale as a means to further establish kris as a character. after all, if you aren't a monster, and even seeing pictures of other humans (creatures KNOWN for attachment and connection to each other) makes you viscerally uncomfortable, then what exactly does that make *you?* someone who has a motivation to be making dark worlds in order to be around darkners (who are distinctly Not Human Or Monster), that's who.

Great video as always, never could've guessed the answers were infront of us lol

It's a little ironic how thorough analysis can do you in like this. I thought of UT and DR being parallel realities right away, just on intuitive level and didn't really question it. Mostly because the first time I ever heard of multiverse theory was in the context of quantum particle observation, the entire point was the the two realities could be practically identical, yet this one detail (the state of the particle) is the one difference. You made such elaborate effort into research and rationalization and yet it backfired. Doesn't undermine the work you've done however, it's still amazing content and it's cool you keep it a possibility to be wrong!

Hi! I know that is A BIT too late for questions, BUT. I really like your theory and want it to be true, although some of facts do not add up. PLEASE could you share your thoughts on it? 1. Sans remembers us in Deltarune. When we talk to Sans in the end of the 1st chapter he obviously lets us know that he recognises us (probably not Kris, but the player). He winks and gives massive hints that he has already met us, and in the second chapter jokes about the fact that we know about his brother, although he did not tell us about him. How is it possible, if Deltarune is his original universe? Does that mean that he came FROM Undertale TO Deltarune instead and that is why he recognises us? I don't like this idea myself, because we know that our Undertale universe is also not Sans's original universe. Also during the battle with Sans he claims that he CANNOT RETURN TO WHERE HE CAME FROM and that he has already given up. Moreover, Toby said that the “time machine” in Sans’s secret room cannot be repaired. Thus, Sans simply could not have come FROM our Undertale TO our Deltarune, at least based on what we know about him. BUT it's clear that Sans had already met us BEFORE the events of our Deltarune. How did he know about the player if Deltarune is his original universe? If Deltarune Sans is a fake one, the one who created him (the angel for example) must know about us AND Undertale events to trick THE PLAYER into thinking that it's the same Sans from Undertale. But why? Why is it so important to fool us into believing that this Sans is OUR Sans? I'm so confused. Based on Sans's words during his battle and the fact tham the machine can not be repaired, we have to consider Undertale as the last stop for Sans. Then how does he recognise us in Deltarune? Could it really be just an easter egg for those who played undertale before? 2. Papirus is NOT the original Undertale Papirus (and actually knows a lot). Another thing is the INTERVIEW WITH PAPIRUS, where the last question for Papyrus was: "What was your life before you moved into Snowdin?", to which Papyrus replied "There was green grass...", and then Sans interrupted him and closed the question. If this QnA is canon, this means that Papyrus is also not from the original Undertale, because there is no green grass in Undertale (unless we attribute everything to some kind of magical grass or algae, but that would be completely stupid). Moreover, this means that Sans knows where Papyrus used to live and does not want to reveal this secret. Also the dialog during Papyrus's date reveals that Papyrus knows about cars, highways and sun. Either these things exist in his original universe or Sans told him about them. It gets more complicated in the end of the pacifist route, where Papyrus is confused over the sun in the sky. If he knows about it and wants to feel "wind in my hair, sun on my skin", it means that either Sans told him about the sun and that's all, OR that sun, cars and all existed in his home universe, so he understands the concept of the sun, but does not remember how it looks (HE FORGOR). Also Papyrus has a line of dialogue about Sans pranking us through time and space, so it seems that he knows a lot about Sans and his space-time stuff. So we know for a fact that Papyrus is aware of a lot of stuff, but Sans is very good at keeping an eye on what Papyrus says. 3.Regarding the fact that Papyrus disintegrates when dying. Sans also disintegrates, but before that he bleeds, and the idea that Papyrus is a magical monster and Sans is a physical one is based on this fact. However, Sans also disintegrates, we know this because of the sound effect. Moreover, it is Chara who delivers the final blow to Sans, so the blood that comes from their blow can be explained precisely by the fact that at the time of the battle with Papyrus, it was Frisk who delivered the final blow, and it was not so strong as to cause an open wound (on the other hand, his head falls off, which can also be considered an open wound, also Frisk oneshots Papyrus, so...). If Papyrus is truly a magical monster, that means he is not the original brother of our Sans. But considering that Papyrus lived in a place with green grass and Sans DOES NOT want us to know about it, it at least means he is not from the universe of our Undertail. If we stick to your theory, it would mean that Sans changed more than one universe, and in one of them he met our magical Papyrus, with whom he later moved to our Undertail and the time machine broke so they stuck there. This complicates things. 3. How are Sans, Papyrus and Gaster connected? There is also a question about gasterblasters which Sans (and probably Papyrus) know how to use. If it were the original Undertale Sans (and Papyrus) who worked with Undertale Gaster, and then got merged/shattered, and OUR Sans and Papyrus arrived in Undertale AFTER that incident, that would mean that they would not have a way to learn/get gasterblaster. (Unless they used Gasters blueprints, but i feel like it's a stretch). So either they used blueprints to get gasterblasters, they had them to begin with, or THEY were the ones who worked with Gaster but did not merged with him. In that case we don't know ANYTHING about the original ones at all. Interesting fact: the Windings font was created by merging 3 fonts together or something. So the idea of Gaster being an amalgamate of Gaster, Sans And Papyrus is really coming together. Or it's just a coincedence. So we are left with these facts: 1.Deltarune Sans has already met the player either in our Undertale, (which means that he managed to escape it after all), or he has met the player earlier in a different universe/time which we are yet to visit (so for him it has already happend, but for us it will happen in the future). So these hints are either showing that our Deltarune Sans IS our Undertale Sans, OR Toby is tricking us into thinking that way for some reason. 2. Both Undertale Sans and Papyrus are not from our Undertale universe. 3. Our Undertale Papyrus is from a universe with green grass, possibly sun, cars and highways. However he does not recognise the Sun when he sees it in the pacifist ending, which means that he understands the concept of the sun, but haven't seen it or does not remember how it looks. (This idea compliments the theme of forgetting and not forgetting in Undertale and Deltarune). 4. If Papyrus is a magical monster, that means Papyrus and Sans are from different universes (both of which are NOT our Undertale). That would mean that Sans changed more than one universe, and in one of them he met our magical Papyrus, with whom he later moved to our Undertail and the time machine broke so they stuck there. 5. That lives the question: what happend to the original Undertale Sans and Papirus? If they died/went missing during Gaster experiment before our Sans and Paps arrived to Undertale, then how did our Sans and Paps got their gasterblasters? 6. If our Sans and Paps did not have gasterblasters and are NOT related to Gaster on some family-level, that means that they came to Undertale, worked with Gaster, got gasterblasters from him and then Gaster fell into his creation and shattered alone, leaving Sans and Paps to live in Snowdin trying to fix the machine. So they DID NOT MERGE with Gaster. In that case we don't know ANYTHING about the original ones at all. 7. If Sans and Paps had gasterblasters as their own thing, that means they ARE related to Gaster on a family-level, and they had gasterblasters to begin with, that's why original Sans and Paps merged with Gaster into W.D. Gaster, and our Sans and Paps still have gasterblasters just because it's their own thing in general. Also that would mean that Deltarune Sans and Paps could be also heavily connected with Deltarune Gaster. I'm sorry for any misspelling, I'm not a native. I hope you will see my comment, cause I love your theories so much, it would be awesome to get your opinion on my thoughts!

Hey jaru. It's me. You might remember me as a big critic of some of your theories. I gotta say, I don't disagree with a large amount of what you said in this video, in fact it made me rethink a theory of my own that I had been working on for upwards of 8 months. However, I do have one big criticism to put forward here: In your video here, you have stated that Undertale and Deltarune are basically "next door neighbors" in terms of being parallel universes, and I fully agree with that idea, however, this presents a problem; *if the two parallel universes are nextdoor neighbors, wouldnt there only be a single fundamental difference between them?* In your theories, you have stated that differences between UT and DR include enormous fundamental changes, such as the functioning of magic, monsters being made of matter instead of magic, and normal monsters possessing a much higher amount of determination. Now, I understand that you chalk most of these changes up to the "Angel" directly altering them, but you must understand that this doesnt make sense either, as the "Angel" on its own is not a character that exists independently, rather the Angel is merely a title given to the character who fulfills the Prophecy. For example, if one were to do a true pacifist run in Undertale, then the Angel would be Asriel, but they wouldn't gain said title of Angel until they had fulfilled the prophecy by freeing the monsters. The angel isn't a character that exists independently, which is why it doesn't make sense for the angel to be treated as some kind of all powerful entity from the get go. Anyway, getting back to my main point, it doesn't make sense to say that the two parallel realities are neighbors if so much is different between them. On the flipside, if you were to take a look at my own theory, it does in fact follow that there is only one fundamental difference between the two parallel realities, thereby making them "next door neighbors" to each other, and this fundamental difference between the two boils down to just *whether or not Chara exists,* with the other apparent differences (no magic/monsters made of matter/monster DT) all chalking up to Toby intentionally playing word games to confuse theorists, on top of other butterfly effect borne (ie, not fundamental differences) being caused by Chara not existing, for example, Asriel being alive is a direct result of Chara not existing. If you really believe this theory is crackpot PLEASE PLEASE PLEASE look up Goner Kid's dialogue in undertale. He literally talks about a different world in which the only difference between here and there is that a single person doesn't exist, and coupling this with other Goner dialogue about meeting "Suzy" soon, it becomes really interesting.

Ive actually been saving your recent videos for later because my watch later playlist has like 50 unfinished videos that I need to get done lmao. No matter how hard I binge I can't get rid of them all. Anyway hope you understand.

bruh i already thought that video was perfect! jaru at it again. being an absolute CHAD of a human being

This is like the first thing I've heard you say that actually makes sense

So excited for chapters three, four, and five. It's going to have so much text to read...I can't wait!

I always want more after listening to ur theories!

Has it really been that long since the first theory video? I appreciate the scientific method that went into this. So many people are afraid to change their minds when faced with "new" information but it's silly, I feel, to be so rigid. Thank you for being a great role model for changing one's mind

My man’s sounds like a mom when they see their child make anything In a good way

10:15 "But to answer this question, we're going to have to talk about parallel universes"

Jaru, it's really admirable of you that you accept the mistakes and flaws in your theories and try to rework them!

Parallel realities implies the existence of transversal realities. A transversal is a line that intersects with two or more parallel lines.

YES yes!!! Another video!!!! Thank you!!!!!

It is impossible to tell and as you said it doesn't matter. Imagine that Deltarune takes place in an alternate Undertale timeline where a monster gained 8 human souls and became a god. They used their power to reshape their universe into Deltarune, removing magic from humans and monsters by restricting it to the dark world and what-not. Now compare that to a Deltarune universe that was always the way it is in game (separated into light and dark, history, etc). The two would still be running "in parallel". Theres no difference. In both scenarios it would have been possible for sans to use gaster tech to travel from Deltarune to Undertale then get stuck there due to the machine breaking. Saving and loading only effects one's current reality, so that is consistent too.

12:30 if Doctor Who takes place after 1936 (idk never watched) that might be because the Hindenburg Zeppelin never crashed in there resulting in it becoming not an universe but an a alternative timeline

Except that, even with a lot of determination, you can't go back further than when you obtain the power. Frisk can't go back before you fall into the underground, Flowey can't go back before he becomes of a flower. So Sans literally wouldn't be able to go back to the branching point of the two games. He wouldn't even be alive back then. The machine is able to go laterally to another timeline, which is not something determination can do, or at least we don't know if it can do.

Couple things. A: Your videos are stellar as always. Love your content, as I feel like you're one of the best at finding details in every corner. B: this interpretation also aligns with something Toby Fox stated during the interview after Chapter one. "All the characters from Undertale are exactly the way you left them." They're the same because the Deltarune cast are literally different individuals. C: your telling of events also, ironically, fit the old "Sans is Ness" theory in a thematic way, since what Sans would have done is literally what Ness did. Just found that interesting.

How convenient, literally just finished Chapter 2 for my first playthrough. So happy I can finally watch these.

Long day with friends, get home late at night, get a good buzz going, see fresh new Jaru video.... This is the perfect way to enjoy the rest of the night. Thank you Jaru.

" there will be major spoilers for both deltarune and undertale, so please play them both before watching this" *speedrunning noises* "but first, we have to talk about parallel realities"

This a comment of the fan art section it took a whole second watch through to notice the Obereon by MakeYourOwnDeals1997 had a hour glass as the hammer.

Some of the riverman's dialogue from undertale directly foreshadows deltarune. There's a ton of lines about water, and one about "the song that comes from the sea". I haven't done enough research on it to say what every line of dialogue means, but could you do a future video about it?

the james webb telescope picture being the thumbnail makes me happy

I realized something that I'm not sure if anyone else has, and it lines up with the sans theory. Notice how UNDERTALE's title screen font is all caps while inversely deltarune's is not capital, just like how papyrus speaks in all caps while sans doesn't use capitalization. It could be a coincidence, but it could mean something big if we meet papyrus in a later chapter of deltarune and he either does or doesn't follow his undertale capitalization pattern

7:09 Minor problem, sans likely couldn't steal one of the existing souls from Asgore. Flowey makes it very clear that he could never manage it himself even with his godlike powers. The only reason flowey gets them is because asgore reveals the souls when the fight starts. As for killing a human, he probably could. However we are likely the first human to show up after sans did, and since we can't permanently die...yeah that would make obtaining our soul rather difficult.

I've always thought "alternate universe" because a key twist in Undertale's narrative is learning that the year is not 201X, but rather 100 to thousands of years in the future. Meanwhile, Deltarune has the far future (main storyline) characters like Alphys, Undyne, Sans, etc. AS WELL AS 201X era characters like Asgore, Asriel, Toriel, and Rudy. Remember Rudy is long dead by the time of Undertale, and Asgore and Toriel only haven't aged because they are Boss Monsters. The only way for those characters to exist at the same time is for it to be alternate universe. Edit: Hey!!! Your parallel universe thing uses my exact reasoning for disagreeing with your last theory on this. Spider-Man and Doctor Who are great examples of it.

I always assumed this was the case because Toby has pulled on fandom stuff before when he does extra content (like the Kris Red Eye rumor resulting in him adding that to the animation in Chapter 2). The biggest concept in the fandom, derived from Sans' dialogue and Alphys' statement about alternate universes, is Parallel AUs with alternate undergrounds with gimmicks like everyone being edgy, or everyone's roles being swapped, or Sans doing off the deep end and farming everyone for EXP to stop Chara, etc. So in a way you can easily look at Deltarune as Toby Fox officially joining the fandom and making his OWN AU of Undertale. (Or, really, Undertale being an AU of Deltarune since Deltarune was written first but you know). The interpretation of him making Deltarune as an Undertale AU fits with the vibe of some stuff he worked on in the past too, like Homestuck, where referencing and integrating fan concepts (like the Beta Trolls being parodies of what people who hated certain characters thought the characters were like etc) was very common, and self-referential stuff like having characters in the world that were interacting with the comic like the readers did IRL to comment on reader tendencies was also heavily a thing from the beginning. So similar concepts being applied and explored with Deltarune checks out completely tbh. Taking that concept even further I wouldn't be surprised if once we start getting old Undertale characters in Dark Worlds (Like Toriel in Chapter 3) Toby uses it to comment on fandom biases and incorrect "Fannon" of the characters. Like how everyone stereotypes Toriel as perfect goat mom when shes actually kind of overbearing, bad at addressing her children's mental health concerns, and an implied alcoholic.

One thing that may also be possible is that timeline manipulation only allows for the modification of existing timelines, rather than a return for one’s home timeline.

Fantastic video! It's so nice having a big Deltarune theorist say, "hey, Toby DID say that these are separate worlds, but maybe there's a point to that beyond just characters." So many people seem to disregard the thought that there's any connection to Undertale at all story-wise. "Gaster isn't involved" they say, in a game full of Gaster easter eggs. "The story of Undertale is done, it won't be expanded upon here" they say, when Toby said years ago on his Kickstarter that his next project would expand the world of Undertale and it's characters. It legitimately makes my head hurt. Toby is obviously lowering expectations for a greater impact, but it blows my mind that people don't even consider the connections. Gaster literally promotes the chapter releases on Twitter and people shrug it off. Ugh. Weird to me how part of the community finds things like shipping Berdly and Spamton more interesting than the speculation and deep lore. These are insanely well-written games, and are way more than just goofy, Earthbound-inspired comedies. Anyway. Again, fantastic video, always a treat to see a new upload from you.

Honestly, after I watched your original theory video, I immediately came to the conclusion that Undertale and Deltarune were set in parallel universes, and watched the rest of your theory videos with this in mind. I was huge Doctor Who fan around the ninth-tenth Doctors era, so that's probably why I instantly thought of parallel universes. To be fair, whether the two games are set in alternate timelines or parallel realities doesn't make any real difference, since their consequences are functionally similar, so don't feel bad. You still made a lot of really good points, and parallel realities are a kind of in between of the other two possibilities, so you were kinda right anyway. It reminds me of your Shadow Crystal video, where your theory that Deltarune is stuck in a time loop meant that you had the benefits of both the "show the past" and "show the future" theories. The real answer was both and neither!

I have a theory. What if the underground in Undertale is actually a dark world, and the Surface is the light world? This would explain how there is magic in Undertale because Undertale takes place in a dark world. The Core could be a machine that harnesses the power of the fountain to provide other forms of energy other than magic. And perhaps the monsters when on the surface lose their magic, but are able to continue life due to the Core providing just enough energy to keep them alive while on the surface.

Great video as always ☺️ I actually have a theory to share! I theorise that Kris killing Asriel was intentional, as part of a plan to change something (there are various possibilities, but likely something angel related) like an inverse of Chara and Asriel.

Good video 👍🏻♥️ Totally agree in this always thought about Deltarune as a AU despite your first video even though I go with all your theories so far. Just because I came to the same conclusion you did now. And STILL can go with all your theories. :D (because I really love your ideas and pray they'll become true 🤧👌🏻) though I admit I never thought of parallel AU more of Universes which are like extremly "close by" or near to each other But thats just basicly the same in the end 🤣 now I am happy you are sharing now this idea with the same conclusions :) Btw really impressiv fanarts. Shout out to all those crazy talented artists :)

My understanding of timelines in a multiverse is that every choice can spawn a new timeline that gets progressively more distinct from the original with every deviation, until it becomes unrecognizable from its original. This leads to infinite timelines placed on top of one another with the smallest differences, like pasta in a boiling pot, all vaguely similar but distinct from one another despite how they tangle up. Then there are more drastic cases, like a world where Earth never formed and intelligent life had to develop elsewhere in the solar system for one example of an infinite number. Undertale and Deltarune are alternate timelines with differing starting points leading to differing outcomes. In one, Monsters are made of magic and turn to dust upon death. In another, Monsters have physical bodies, blood, and Determination.

What if the Roaring is when parallel realities crash together?

My personal theory is that by the end of Deltarune’s story some kind of cataclysmic event will occur that leads into this world being shattered and reshuffled into what becomes undertale and possibly other reality’s. Would also explain why we’ve seen normal versions of Gaster followers in deltarune. These could’ve just been normal people that something unfortunate happens to or they chose to follow the wrong guy.

Jaru, in your knight video you told us some people were calling you cringey back en the ralsei video. And honestly, I disagree SO MUCH from these people. It felt super natural bc the video had been building up to this, we all knew something REAL BIG was coming, and we were not disappointed. The part where you got all excited was the best part to me. I enjoyed it much more than the rest of the video. So if you feel like getting dramatic like that again, go for it! Its really endearing. I hope you keep making these videos, theyre truly amazing. Thanks for all your hard work!!

I would love to see a theory on what the lyrics in the background of the World Revolving part in BIG SHOT are saying and what they mean, would be interesting to see

The fact that he's not saying "Parallel Universes" means he's aware of the Super Mario 64 jokes that would follow.

most underrated youtuber

I cant belive how only if we are in chapter 2 we can already decuct plot twists and endings in chapter 7,

I think that it's possible that in the Undertale timeline, W.D. Gaster accidentally fell into his DETERMINATION Extractor, rather than the CORE, and was shattered into pieces, which is why in the intro scene when Gaster is talking to Kris, he is talking in a different typeface, as the Wing Dings part of him, the more fun, caring side of his personality was ripped away from him along with his morality, which is why he may be a villain. I think that he landed in the Hometown and went into the shelter and created his own little Dark World that only he knows about. After a bit of time, Kris stumbled into there and this is where the connection between Kris and Gaster was formed. After this, Gaster uses Kris as a vessel to open Dark Fountains (Dark, darker, yet darker perhaps referencing 3 dark fountains) and once he does, he'll become all powerful. What makes this tragic is that when Gaster is not controlling Kris, the player is, making it virtually impossible for Kris's true feelings to be realized. I think that throughout Chapters 1, 2 and likely the next few, it will be a battle between Gaster, us, and Kris themself. Or maybe I'm totally wrong, who knows.

Something that doesn't contradict the theory but is kinda related & just kinda bugs me because I don't think we have an answer yet & I don't know if we ever will: Why does Asgore know he's already killed you *before* you tell him? That's not like Sans' ability to read faces or Toriel's deja vu about a pie. Asgore was absolutely certain he'd already killed you as if he fully remembered it. Why? He obviously can't reset or else none of the plot would've ever happened. And why is it seemingly just that one instance? Does he have some kind of special awareness of deaths he's caused, even across timelines & maybe across dimensions? Is that why he has flowers in the colors of the human souls in Deltarune? Because he knows he caused their deaths in another reality & he's commemorating them out of guilt? He can't just have perfect memory of all resets because he's still surprised to see you even if you reset. Maybe that's even why he so quickly accepts that he has to kill you. Because although he didn't know you were coming right then, he knew timelines/realities existed in which he'd killed you even if it wasn't the same him yet or the same you.

Oh my god. The AU sans fans are going nuts right now

Theory The man behind the tree is the Riverperson meaning they are the Riverman meaning the eggs are normal eggs. Now I know what you are thinking, then how do you meet them between time and space. Because of their boat they got it from Toby Fox meaning they are friends and in deltarune he gave him admin commands. Hire me

Don't forget the bunny shopkeeper in snowdin, she literally says sans and papyrus "appeared" out of nowhere

Alrighty, so, I kinda predicted alphys being in this episode from the recent comments I made, which is pretty cool. But anyways, great video as always dude!! Something that I find really impressive is you can make a theory on these games that sound crackpot at first, then make me fully believe them by the end of the video, lmao. Keep up the good work man!

11:31 “To answer that… We have to talk “Parallel Universes”

And here I am, the final Deltarune video. I'm... caught up, huh. Interesting theory, I don't have much of an opinion of this one, since this is just a new revision. I'm impressed you had the courage to admit your mistakes and rework a whole theory, but other than that all I can say is I'm looking forward to that Spamton video! Hopefully all of my comments weren't a drag or anything, I think I left atleast one comment on every single video lol

gotta love the Jaru Cinematic Universe

The problem with the sans being from another world theory is that it can mean something else. It can simply mean sans was trying to go back in time and stop your genocide,but he realized there isn't a way to do that. Is it possible? Yes,i like to think anything is possible untill proven otherwise. Is it as obvious of a answer as you claim it to be?i don't think so.