LexDotHam reveals the Manhole Theory in Deltarune, linking sewers, Hometown, and dark worlds with deep lore insights.
Key Takeaways
- Jackenstein’s maze is a detailed sewer map that connects Hometown’s buildings to the dark world.
- Sewer overflow during heavy rain links the dark world with the lake, expanding the game’s environment lore.
- The cistern and sewer system explain various in-game events and locations, including the shelter and Castletown.
- Real-world sewer mechanics inspire the theory, providing a plausible explanation for game phenomena.
- The theory integrates symbolic and biblical imagery to enrich the understanding of Deltarune’s story.
What the video covers
- The video introduces the Manhole Theory, connecting Deltarune’s Hometown sewer system to the dark world and game lore.
- Jackenstein’s maze from the Jack and Stein fight is analyzed as a sewer map that aligns perfectly with Hometown’s layout.
- The theory explains key mysteries such as what lies beneath Hometown, the nature of Castletown, and the lake’s significance.
- It explores how sewer overflow connects to the lake, creating a continuous dark world during heavy rain events.
- The video links in-game events like Carol shutting down the city and the disappearance of Deaths to sewer system failures.
- A cistern beneath Hometown is identified, tying into game mechanics and story elements involving water treatment and overflow.
- The map includes every house in Hometown, with specific references to Asgore’s house and Chris’s house, suggesting deeper lore connections.
- The theory draws parallels between real-world sewer systems and the game’s dark world mechanics, including overflow and flooding.
- Biblical and symbolic references such as 'the roaring of many waters' and 'wormwood' are discussed to deepen the narrative context.
- The video encourages community discussion and critique, acknowledging potential holes and inviting theory refinement.
Chapters
- 00:00Introduction to Manhole Theory and initial observations
- 01:38Jack and Stein maze as a sewer system map
- 03:50Real-world sewer mechanics and overflow explained
- 05:59Linking game locations: key, tutu, and cistern analysis
- 07:58Mapping every house in Hometown to the sewer system
- 10:04Implications of the sewer map and Roaring Knight disappearance
- 12:35Symbolism and biblical references in the theory
- 14:49Conclusion, theory critique, and community engagement
Full Transcript — Download SRT & Markdown
Speaker A
Deltarune is solved, people. I'm serious here. I genuinely think this is going to blow the lid off the Deltarune theory crafting community, and I call it manhole theory. So I started thinking about this when I replayed Earthbound, and I found that the manhole in the supply closet
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of the four-side museum, the one that leads to the sewers. I just thought that was interesting. I thought this is the sort of thing that Toby Fox would totally have played, and it kind of, to me, explains why there's
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such a weird fixation on both closets and manholes. But then I saw the maze that really changed everything.
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But first, I'm gonna—First, I'm going to lead in with all the questions that this theory answers. Lead in with all the questions that this theory answered. It tells you what's underneath Hometown. It tells you what Castletown is. It tells you what's in
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the lake. It tells you what's going to happen in the Weird Reef. It tells you what's going to happen in Chapter 6. It tells you how Deaths went missing.
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It tells you what happened on that day. It tells you what E-Ram is.
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It tells you what the Roaring is. It tells you why Carol shut down the city in Chapter 4. It tells you how the night gets around Hometown. How Ralsei gets around the Dark Worlds. It tells you everything. Thing. So if you're still here,
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please drop a like and subscribe, especially if you're into—So if you're still here, please drop a like. Completely unhinged Deltarune theories like this one, because this is going to be a wild ride. And even if you aren't, do it anyway. Now buckle up. This is
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either the 8th or the 9th maze in the Jack and Stein fight. And when you're playing this in the game, you only ever see small bits and pieces of it. So it never really clicked to me. But it wasn't until I saw this
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full version that I thought, wow, this is funny. This looks like a sewer system, like how a sewer system would work in real life. And then I started looking at the arrangement of the lines. And I noticed that this looks
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suspiciously familiar. Hometown. You look at the arrangement of the streets and where everything is laid out. And now look at it with Jack and Stein's maze superimposed on top of it. You've literally got every building in Hometown directly connected to this sewer system.
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It connects to the shelter. We already know that the shelter contains a dark world.
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We've seen this firsthand. So this means, by definition, anything else connected to the shelter is also part of the dark world. So this whole sewer system, everything you're seeing here in pink, that's part of the dark world, and that includes the
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supply closet in the school, Castletown. Now obviously there's an entrance in the shelter, but what about the lake? So let's take a look here. What's this? A suspicious manhole-sized hole exactly where Jackenstein's sewer map predicted it would be?
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Huh, interesting. Very, very interesting. So all this seems kind of weird, right, and almost pointless? Well, let's start—let's look a bit at how sewers actually work in real life. So on Jackenstein's map, you have those two big pipes at the bottom. There's two big pipes at the bottom, and that's
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how things work in real life too. And that's how things work in real life. You've got sewage and stormwater. So under normal conditions, that water just goes to the waste facility and gets treated, but when it rains, the amount of water that is
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entering the system can really just exceed what it can process, and so that water, it overflows, and that little pipe, it goes straight out to the lake, and that's what those overflow tunnels are for. Okay, so now let's look at
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what this looks like when it's on Jackenstein's map. So we got Hometown up here, and the water treatment facility down here, and all the sewage comes down, and under normal conditions, it just flows to the treatment facility. Notice how what's happening on
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Jackenstein's map is exactly how it would work in real life. Same basic system, but when it rains, that's when things get a little interesting,
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because then the water doesn't have anywhere really to go. But what happens if it's like a lot of rain,
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like biblical Noah's Ark levels of rain, the kind of rain that the Bible describes as the roaring of many waters? Well, that wastewater doesn't have anywhere to go. And the place that you're trying to dump the water to, well, it's
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filling up too. Now, sewers are dark, obviously, but once you get deep enough underwater, Now, sewers are dark, obviously. A lake is pretty dark too.
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And when those lakes rise up high enough, there really isn't a meaningful boundary between the darkness of the lake and the darkness of the sewer. They really become one continuous space. The lake is now one giant dark world connected to an already very giant dark world.
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But something really didn't very... totally line up for me. And I was actually about to scrap this video because I couldn't explain this. This little nub here at the top. So when you're playing Deltarune Chapter 4, this little area is
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where you get the key and then Jackenstein takes the tutu and brings it back to you. And it didn't match up with anything else in Hometown or... did it? Spoiler alert: it does, because Chapter 3 provides us with the room that
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just so happens to literally be shaped exactly the same as that little nub, complete with a wearable garment that you need assistance in order to fetch—the shadow mantle, the tutu. It's the exact same shape. What does that actually say? Because
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that's my problem with a lot of my theories. If you've seen my shorts, I do a ton of very—that's my problem with a lot of my theories: unhinged shorts. And the reason I don't turn those into full-fledged videos is because they don't actually
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say anything. It's just, oh, this is pretty cool, this is pretty weird, these things are anagrams for those things, and it's fun for sure, but this is a cistern. So it's a large underground chamber for collecting water, and look at those
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those inconveniently shaped columns all around you. You can almost feel ERAM's bullet patterns firing down. So a cistern, it's like a big overflow tank, usually for a water treatment facility. It can actually be used for a lot of different
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things, because water, weirdly enough, is useful. Like, for example, a lot of times they'll use that overflow water to store radioactive waste, because it's a really good barrier for radiation. You've got your cistern and you've got your—your water treatment facility. You've got
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your cistern, and you've got your—that's that it's feeding and it's getting fed from, and we have the two exits: one down here, which is where little Chris comes in from, and one up here, which is where little Chris comes
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out from. And again, this isn't speculation; these are facts. We have seen these in the game. We have seen little Chris enter from the bottom and exit from the top. In a real sewer system, both of those exits would lead you up to
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the sewer, which in turn would lead you up to the streets. Now, you'll notice I did something fun here, because Jackenstein didn't just give us a map to the sewers. He gave us a map to literally every single house
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in Hometown, and they fit perfectly, even down to the little tree next to Asgore's house, even down to the fact that Asgore's house is the only one that has two—to Asgore's house, even down to the fact that Asgore's house is
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the only one that exits. Now this one up here, Chris's house, I'm gonna make a video about that because there's some stuff there. But notice exactly where the map predicts that manhole is going to be. Exactly where the sewer map predicts the cistern entrance is going to be. Also,
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makes a lot more sense now how the Roaring Knight was able to so quickly disappear with Asgore. Now just—How the Roaring Knight was able to so quickly disappear with Asgore. Now, just in case you're not convinced, I want you to think about
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the manholes near wherever you live. They've usually got some generic labeling slapped on top of them, like this one. Waste drain or whatever.
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on the manhole. Maybe there's four letters that kind of slip from your memory. With those letters that are left over, you can rearrange them a little bit and get a word. Shadow. So you can probably see where this is going here, because if you rearrange the rest of the letters
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that are left over, mantle shadow mantle Eram look I'm not saying this is definitive but like come on especially considering that the little orange thing that makes Eram it looks very suspiciously similar to the tutu that you're supposed to fetch in Jackenstein's maze the
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same part of the maze that is laid out identically to Eram's layer in the Eram's lair and the sword root, the same location that's literally predicted by sword route the same location that's literally Jackenstein's sewer map and Jackenstein's map of Flower King. But once you start stacking coincidence on top of coincidence,
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on top of coincidence, it doesn't sound so crazy anymore. Now, look, I didn't want to do this. I really, really did not want to do this, but I'm doing it. Look, I told you it was going to get
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crazy. I told you things were going to get unhinged. You knew I told you things were going to get unhinged. You knew. this was coming. W .D. Gaster is a perfect anagram for the phrase D .G .R. waste. Now, here's the thing.
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That is an actual term. It's waste that's stored in a deep geological repository. This is an actual method of storing radioactive dangerous waste deep underground in a sealed facility specifically designed so that nobody goes poking in or out around. there again
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this is a real thing you can google it and because these places are sealed and therefore they're hard to inspect directly one way of monitoring them is with a method called a digital twin d t it's a digital copy of the original system that you can monitor instead of the real thing
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sound familiar and the process for pulling information from a digital twin it's literally called dt extraction again this is not just some made -up thing you can google it you've got a waste storage method that exists in the real world that is a direct
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anagram for wd gaster and the accepted method of examining that waste is literally called dt extraction and it involves making a copy of a system and monitoring that copy. I mean again it's not definitive but it's pretty freaking weird especially when you look at the other
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radiation parallels within Deltarune and beyond. Obviously Toby radiation fox but look the original colors of the radiation symbol are pink and gold just or pink and gold just like the two colors of polonium which is one of the like the two colors of polonium which most deadly radioactive chemicals in
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existence pink and gold now there is a reason why I took this detour into crazy town because the the radiation imagery here is actually relevant beyond just oh that's cool because people love making things out of radioactive stuff it's glow -in -the -dark it's it's eerie it's cool there's a real
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-world company called the Finton glass company Well, there's a real world company called the Fintan Glass Company there. They're famous for their uranium glass sculptures, which glow in the dark because of the uranium. They're real collectors items. You can
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Google it. You can look them up. You can find them. And oddly enough, the two types of sculptures that they're most famous for are cats and eggs.
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And so when you turn out the lights, just like vanilla ice, they glow. this glowing cat already looks kind of like a hellish friend lookalike, and look at this egg. I mean, here's the thing. The Fenton eggs were almost always painted and decorated with flowers, and one of the most common
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flowers that would be used as decoration was the golden aster, G. Aster. So, we have these gaster eggs, but why are they relevant again? Yeah, yeah, I'm getting to it, don't worry. Because radiation disposal is really hard. It's why they make these big, giant, deep
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geological repositories where waste is buried beneath the earth. But, just like cats, people are very curious creatures. And as we learned in the Chapter 5 lore drop, cats... can bite very, very hard. And they're tenacious.
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Even a small bite can be enough to prompt a grave warning from a Hatsune Miku cat girl. And you know what else can cause a lot of harm with just one little bite? Radioactive materials. There's a reason why those
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radioactive capsules you see on Reddit and spooky images is have literally drop and run written on them because holding them even for just a few seconds have literally drop and run written on them. can cause enough radiation exposure to literally kill you either just right then and there or slowly
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and the symptoms of that whole killing you slowly side of radiation poisoning are suspiciously similar to the symptoms of rudy's illness and history is absolutely littered with incidents where people are snooping around areas that they probably shouldn't be snooping. incidents where people are snooping around areas that they probably shouldn't be
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Maybe it's a scrapyard worker, like in the Guiana incident in Brazil in the early 80s. Or, you know, maybe it's just a bored kid poking around their local town because there's literally nothing else to do. Maybe they find, just like our unfortunate
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scrapyard worker did, a glowing blue egg -shaped capsule just happens to be filled with deadly radioactive cesium crystals. It just happens to be filled with deadly radioactive cesium crystals. Now, maybe as a prank, maybe as a gift, they send
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that glowing blue egg to a friend, or possibly a neighbor. And maybe that friend, that neighbor, that something else. Maybe she's got a dad who's naturally a little bit suspicious of you. And maybe that dad opens the capsule, and then gets a full
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blast of radiation to the face. Maybe that bored kid realizing what they've done tried to get rid of the evidence by, I don't know, flushing it down the toilet. Maybe that bored kid, realizing what they've done. Fun fact here, cesium has an
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extremely violent reaction to water content, enough to really wreck the inside of your pipes. Certainly enough to dissuade you from trying it again. And so, maybe after your mom yells at you for putting a bath bomb in the toilet,
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little does she know. Maybe you just try and put it right back where you found it, right back into Eram's lair, the cistern, built to harvest overflow wastewater and use it to provide a barrier for radioactive material. Which, again,
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cisterns are used for that purpose. As long as the facility is well designed, it works. But if it's not? so let's talk about the roaring, because when it rains, especially if it rains heavily, it can do some pretty
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crazy things to a sewer system. When it rains, the water, it has to go somewhere. The water treatment facility. The water flows from the town and under normal conditions flows into the cistern that protects the entrance to the deep geological repository.
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You know, that home to ERAM that we just looked at. But when it rains, and it rains heavy, the waters start to overflow. And, well, we've got ourselves a flood. And this sort of thing, by the way, is why
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playing in and exploring sewers and cisterns is insanely dangerous. Like, don't do it. Because water can fill up and trap you before you even realize what's happening. And it might not even fill completely and drown you. well completely and drown you it might
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just fill up so much that all your exit It might just fill up so much. roofs are cut off and if it's dark so this is what that sort of thing looks like in the real world all that water overflowing
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and flooding into the treatment plant the water from the lake backs up into the overflow pipe and it floods into the treatment facility but what happens when the water gets even and higher higher than high some might say well the water doesn't have anywhere to go higher higher than high
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somebody but the sewers themselves and this is where the roaring really starts the roaring of many waters as the book of revelation might say because once the lake is not accepting overflow and once the facility floods the water doesn't have anywhere else to go
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it starts backing up into the sewer network itself and once the system is full completely pressurized the network itself and once the system is treatment plant is full the lake is high the sewer is full there's only one place for all that water
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to go up and out hell's roar bubbling up from the depths up through the drains up through the sewers up through the pipes up through the manholes through every opening that connects the town above to the darkness beneath
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it yeah flowery was right there is something dark this beneath it yeah flowery was right there is something dark growing underneath hometown and this is not some made -up hypothetical thing that oh how funny would it be this literally happens in real life
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you can google it manhole geysers and i mean they look pretty dark fountain coated don't they so think about what the roaring actually looks like the entire buried darkness within hometown just breaches the surface a literal rain of filth town just breaches the surface a literal rain of filth roaring from
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below complete with the darkened eyes of these drain valves look them up duckbill drain valves that just happen to look exactly like the darkened eyes but this is why all the radiation talk was important because let's be honest poop raining from the sky
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yeah it's a funny imagery but that would really be kind of an ignominious end to an otherwise beautiful story the radiation piece it gives it a level of gravity beyond just it creates real consequences from the roaring beyond just a gross out scenario because that water
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if it's been contaminated by improperly handled radioactive material that's an existential threat especially relevant considering the the cold water fell from the top of the sky prophecy. because cold water creed Because Coldwater Creek, that was a famous example of radiation
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-tainted water supply that literally rained cancer from the sky down upon its residents. Pressurized water tainted with radioactive waste bursting forth from the ground.
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That's a world -ending event. It's a disaster of frankly, biblical proportions. Now speaking of ham -handed segues, the book of Revelation repeatedly describes commanded segues the book of revelation repeatedly describes the roaring of many waters and revelation 19 in specific gives us then i heard what seemed to be
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the voice of a multitude of tones like the roaring of many waters crying out hallelujah a multitude of tones just like the chapter 4 prophecy panel the roaring of many waters This is the same book, by the way, that describes the fallen star that wept
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a river of bitter tears. It's the same book that talks about the dragon and the seven seals, and basically one allegorical mulligan stew that Deltarune and Undertale, and basically every other story, draws from. Like, for example, in that chapter 4 church book that talks about the fallen star, the one that
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wept the river of bitter tears, that's language cribbed directly from the book of revelation and that's language cribbed. that star that fallen star has a name wormwood would you like to know what the ukrainian word for wormwood is
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chernobyl you know the single most famous radiation disaster in modern human history and then we have that word hallelujah which when i hear it there is exactly one place that my mind goes.
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And that's the season one finale of the hit early 2000s teen drama, The O .C. But, second place it goes, is the haunting Tom Waitzian growl of Leonard Cohen's original version of the song Hallelujah. One of my favorite songs
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of all time. In vain, I don't even know the name, but if I did, well really, what's it to you?
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There's a blaze of light in every word, it doesn't matter which you heard, the holy or the broken, hallelujah.
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My superpower as a Deltarune theorist is that I'm a big old fart. I just turned 40 this year, which means I spent my entire life steeped in the exact same cultural references that have guided Deltarune so heavily. So the haunting
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duality of this song, a song that's so heartbreakingly sincere that it almost just almost loops around. Breakingly sincere that it almost just, almost loops around to irony, you know, just like Deltarune. It's a game that's almost defined by its emotional whiplash. One minute
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you're raging at Flowery for being a total jag, and then you're laughing at him because he's in a bathtub, fully clothed. And then you're absolutely bawling your eyes out when he straight up gets the Sayaka from Danganronpa treatment.
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And then you get to watch as basically all of his friends slash children die in front of you And then you get to watch is basically all. while thanking you for watching their dream. Yeah, Deltarune knows a little bit about emotional duality. And
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even this lyric, there's a blaze of light in every word. There's duality there. Just like the Deltarune prophecy, there's an obvious holy and broken interpretation.
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The holiness of bringing light. But do you know what the Latin term for light bringer? is lucifer the son of the morning hello ben shahar the shining one son of the dawn the morning star and it's not like the bible came up with this concept ancient mythology is stuffed
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full of this sort of duality the bringer of light who flies too close to the sun icarus phaethon prometheus etana bali atar zolotl orpheus and eurydice Ana, Bali, Atar, Zolotl, Orpheus and Eurydice, I mean, light or dark, holy or broken. We're not choosing sides here. The light shows up
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either way. So where does that leave us? Well, manhole theory, it tells us everything that we need to know about the past, the present, and the future of the light world. In the present, Jackenstein's map shows us the sewer
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network beneath hometown. That's the sewer network beneath hometown, and this map clearly shows Eram's lair. And this map clearly shows ERAM's light. Eram's lair is in the water treatment facility, and it's the entrance to the depths. is where the radioactive material is being
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stored beneath hometown. This entire network, the sewer, the treatment facilities, the depths, are all connected in darkness. When the lake level gets high enough, that darkness joins with the darkness at the bottom of the lake. This is why Ralsei can traverse
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through dark worlds so easily. world so easily this is how the night can get around town without being spotted this is why This is how the night can get around town without being spotted. the night had to flee on foot from chris's house
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because the pipes got destroyed that whole system is failing and this is why carol shuts down the city in chapter 4 after it rains and then we have the past someone found the radioactive waste beneath the surface of hometown that someone tried to
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make things right and that attempt to make things right went horribly wrong it rains the lake rises, the sewer floods, the exits get cut off, so they descend deeper.
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the lake rises the sewer floods the exits get cut off Something happens. Someone disappears. Des is gone. Asgore blames himself.
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And Eram's lair represents exactly where this occurred. And then the future, because that's what you're really here for, the theory. Well, I've got some theories for you. In Chapter 6, we get the shelter key. Chapter 7, Side A, the heroes
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enter the facility. through the shelter, Chris Susie Ralsei. In Chapter 7, Side B, the heroes enter the facility through the lake, Chris Noel Ralsei. Both routes converge in the same enormous underground dark world. And in the light world, it's going to rain so hard that the system
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fails. The roaring. And the roaring is when that hellish, irradiated water. brewing beneath the surface of hometown, it bubbles forth from the depths, it cracks the earth, it shoots dark fountains of fatal poison upward from the ground, and cold water
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falls from the top of the sky. And that's it. Now what's really interesting about all this is it answers so many questions, and yet it still leaves so many unanswered. because sure manhole theory tells you everything you need to
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know about the light world but it basically tells you nothing about the dark world itself which is a line that is so sharp so distinct that it feels deliberate we have hint upon hint coincidence upon coincidence upon coincidence to the point where
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you really can't look at all that evidence and think okay there's not something here maybe not exactly this but something and really to me the strongest retort the strongest argument is that it doesn't say anything it doesn't tell you who the knight is
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it doesn't tell you what the angel is it doesn't tell you what the angel's heaven is it doesn't tell you the meaning of the prophecy it doesn't tell you what Ralsei is what the shadow crystals are actually for what the eggs are what's
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friend who are the titans what are the titans what are the rules of the dark world who's talking to us at the beginning what happens to the vessel and yeah what does gaster actually have to do with any of this manhole theory
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can't answer those questions those are questions about the past present and future of the dark world which is for the best because it would truly be boring if every mystery of deltaroon were solved especially if it were solved with something
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so mundane i can't think of many things that would disappoint me about the end I can't think of many things that would disappoint me about the ending to Deltarune, but if everything came down to this and only this,
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I'd be a bit bummed. Because I didn't fall in love with Deltarune for a secret plot about accidental eco -terrorism. But that's the beauty of this, is it answers all those boring light world questions so that we can turn our focus
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to the dark world. Because that's the real heart and soul of the story. not not the traumatic events that happened out in the light world but rather how the individual characters process that trauma and how that trauma turns into narratives and how those
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narratives turn back into reality and look here's the thing about this theory it makes some really wild absolutely buck wild claims but they're actually pretty low stakes it's low risk high reward because if i end up being right i'm gonna look
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like a goddamn genius and if I'm not well none of this really tackles the stuff that's actually important so to that end take to the comments and tell me all the holes in this stupid theory because I got to be honest
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this started in one place and it wound up somewhere entirely different the basics of it the sewer beneath the town I believe that for a while now but it didn't seem interesting enough to make a video around because it didn't really seem to
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say anything. And it wasn't until I was researching for this video that the upshot of it all became clear, and it's been a wild ride. So yeah, hop in the comment section, tear me apart, or tell me how much of a genius I
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am. Either way, I plan on making a follow -up video where I address the comments in further detail, because there's been some really cool discussion on some of my other videos about who the night might be, people's personal reactions to the story.
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It's cool stuff, and I want to highlight that. So, while you're at it, while you're commenting, drop me a like. Because it helps the algorithm. And drop a subscribe, too. Bye -bye.
Topics:DeltaruneManhole TheoryJackensteinHometownSewer MapDark WorldCastletownLexDotHamGame LoreTheorycrafting











