#lore docs

Dark World: Waterfall

Because the Dark World was opened outside in the darkest part of the Underground, the Dark World begins to quickly expand and balloon in size, taking in multiple parts of Waterfall.

Sublocations:

Club Cathode (MTT’s House): Fosfer’s Theatre/Night Club.

Ghost Town (General Neighborhood)

Thunderdome (Snail Farm)

Gerson’s Study (messier and less well-furnished than his Deltarune study)

Somber Springs (Expanded Dark World)

The Floodplains (Path to the Dark Fountain)

Story Events

PUAS/Skeleton Crew open the Dark World outside of MTTs house while he watches

The group wakes up outside Ghost Town and are drawn to the town by the sound of Fosfer (MTT’s TV) singing in the rain

Fosfer introduces herself (shes especially excited to see Alphys and MTT again) and invites the Lightners into Club Cathode

Fosfer starts rambling about she was expecting Alphys to bring a certain Darkner with her, prompting confusion until Spamelia crawls out of Alphys’s satchel and reintroduces herself as Fosfer’s old friend and former business partner

Fosfer also introduces Melpio and Thalamene (MTT's Musical Poster) as the directors of Club Cathode's theatre productions and they beg Mettaton to perform a show rehearsal with them which he cooly declines, but promises to come back for later after the party's finished exploring the Dark World

The party explores Ghost Town and discovers that Napstablook was accidentally dragged into the Dark World.

Napstablook wants to go check on the Snail Farm but when they arrive at the Thunderdome, there’s more Lightner NPCs that were drawn into the Dark World, which Alphys realizes is very unusual and potentially very dangerous if the Dark World is expanding in the Light World

Undyne catches on and tells them that her mentor, Gerson Boom is nearby and probably needs help

Looking around though, the party realizes that the Dark World is way too big to easily traverse but Kia appears from Sans’s inventory and says that Fosfer’s “Scene Changes” can help them warp around the Dark World

Sans: “you got shortcuts too?”

Fosfer: “-and smash cuts and paper cuts and salary cuts-”

Spamelia: “As your lawyer, I’m going to need you to [Stop Talking].”

Fosfer: “Hey! I’ve been cutting my salary first! How else am I supposed to keep the LIGHTS on around here?”

To fast travel “in-game” Alphys can message Spamelia to tell Fosfer to warp the party around

The party also keeps passing Shadow Gals around the Dark World who are rehearsing for the Theatre performance be reenacting scenes from Undertale and Deltarune

Fosfer warps the party over to Gerson’s study who is mostly just minding his own business. Gerson asks them what all this Dark World business is about and Alphys gives him the run down.

Gerson says that if the Dark World is expanding in the Light World, he’s been keeping track of all the Monsters he’s seen pass through Waterfall today and gives the party a checklist of Monsters to rescue.

Offscreen, Flowey enters the Dark World and speaks to Melpio and Thalamene, convincing them to capture all the Lightners that the party is rescuing behind Fosfer's back

Undyne, Alphys, Sans, Papyrus, and Mettaton start rescuing various monsters. One of these monsters is Suzy, but nobody gets her name the first time.

After rescuing the last monster, the party reconvenes at Ghost Town to go check up on all the Lightners at Club Cathode. When they do, Fosfer is unable to find them and Sans and Undyne accuse her of trying to keep all the Lightners captive as an audience.

Mettaton jumps to Fosfer's defense, positing that the Darkners are in an unfavorable position of having their existence be dependent on whether or not Lightners are entertained by them. Fosfer however still denies any wrong doing at all which is when-

Plot twist! Melpio, Thalamene, and the Shadow Gals were the ones who kidnapped all the Lightners! Cue escape sequence.

The Theatre Crew chases the party out of town and the party splits into 2 groups

Group 1: Papyrus, Sans, and Napstablook just get into funny antics with the Thunderdome (think like Susie and Ralsei leaving the party in Deltarune Ch2)

Group 2: Undyne, Alphys, and Mettaton make their way back to Gerson. Undyne blames MTT for the situation, saying that all the Ghost Town Darkners are probably bitter that MTT left them behind like he did his family. MTT argues back but eventually Undyne accuses him of abandoning Alphys too which really strikes a nerve and forces Alphys to intervene

Undyne, Alphys, and MTT make it back to Gerson who is acting oddly scared. Gerson explains that he "thought" he saw the King and Queen's dead son speaking to some of the Shadow Gals but has no idea how this could be the case. Thinking on it a little, Alphys realizes that this could be The Flower and immediately tells Undyne and MTT that they need to find the others and book it to the Dark Fountain

Group 1: While Sans and Papyrus are casually talking about everything that has happened before, Papyrus makes a vague allusion to a talking flower that prompts Sans to press for details. Papyrus eventually admits that the flower wanted him to help Alphys with the Dark World experiments which causes Sans to get serious and tell the others that the need to go the Dark Fountain

Everyone meets back up the Floodplains, where they're stopped by Melpio and Thalamene who are holding Fosfer hostage (dangling her by a rope above a pool of water which will probably cause her to short-circuit)

Cue bossfight and the party wins

Mettaton consoles Melpio and Thalamene, telling them the reason why he even asked Alphys to open a Dark World here was because he needed to find a new spark of inspiration and promises to take his poster and other belongings back with him to the MTT Resort

Flowey interrupts revealing that he still has all the captured Monsters and that he's GOING to see what happens when the entire Underground is flooded with Darkness, no matter what anyone does

During his monologue, Alphys and Sans clock that Flowey is the golden flower that disappeared from the True Lab and is the Anomaly they saw messing with the timeline.

Flowey almost wipes the party when Spamelia sends Alphys a file for the Mettaton NEO body which transforms Mettaton and allows him to sway things in the party’s favor and beat Flowey.

Going back to Club Cathode, Alphys confesses to the party about the Determination Experiments and thats why Flowey took on the appearance of Asgore and Toriel’s dead son. MTT apologizes to Alphys for pressuring her so much to work on his body while she was handling such stressful circumstances. Undyne is a bit more conflicted but is still supportive of Alphys, understanding that she was stuck in an unfavorable position.

The party seals the Dark Fountain and Carol immediately calls them, saying that the Underground is in a panic and that she demands to speak with Alphys immediately.

Introduction:

Post-Family Ending (Flawed Pacifist). The fallen human never killed any monsters and befriended Papyrus and Undyne but didn’t go to the True Lab. Asgore is killed by Flowey and the 6 Human Souls disappear. Toriel returns to become the Queen of the Underground and instates a new policy of mercy to any future humans that fall down.

Alphys, desperate to prove herself and make up for her past mistakes calls Sans and tells him to finish his broken machine project so she can see how it functions using the DT Serum as a power source.

Because the Human Souls are gone, Alphys technically has a limited supply of DT left, but she still has enough to run several trials

The power to reset the timeline is still held by the Player and not Flowey. The Player simply hasn’t restarted the game yet since Frisk left the Underground

Gaster is interested in simply observing this timeline to see how his successors' own Dark World experiments go. Being scattered across time and space is very useful for multitasking.

Undertale Characters experience deja-vu of other timelines; select Darkners experience deja-vu of their Deltarune counterparts but to a more subtle extent

The Underground's secluded nature and comparatively limited media network causes the monsters live there to engage with fiction, media and escapism differently. Because their own freedom is not guaranteed, more monsters tend use escapism as a coping method.

The Underground's Digital Media landscape was very limited before the Undernet was popularized and Mettaton became the central brand figure of a media empire. Cable television is new in the Underground and TV streaming and Digital Marketing are very primitive compared to how they exist on the Surface and in Deltarune's Light World.

Backstory Timeline:

Alphys and Mettaton first become friends and start hosting Human Fanclub meetings

Alphys finds a CRT in the Waterfall dump and repairs to gift to Mettaton (Fosfer appears in the Ghost Town Dark World, as Human Fanclub Meetings continue, she becomes the hostess and proprietor of Club Cathode)

Alphys recieves and ignores messages from Catty, Bratty, and other friends (Spamelia forms and is eventually spotted by Fosfer at Club Cathode)

Sans and Papyrus arrive in Snowdin and "assert themselves". (Arriving in the Sea of Silver and Gold for the first time, Kia uncovers the Sky Mantle)

Alphys begins working on the DT experiments, isolating herself except to occasionally work on MTT's body. (Spamelia stops visiting Club Cathode, half of Shimmer City is transformed into "Dimmer City" and Veilance becomes ruler of the Dark World.)

The DT experiments fail except for Flowey's creation. In searching for him, Alphys meets Sans who's an expert in quantum physics. Together, the two discover an "anomaly" that is causing timelines to "reset". (Kia visits Shimmer City.)

Undyne becomes Captain of the Royal Guard and meets Papyrus

Alphys meets Undyne at the Garbage Dump for the first time and shows her "human history books"

Alphys starts working more heavily on helping Mettaton with his entertainment career and he moves away from Waterfall permanently. (The real Mike leaves Club Cathode and the Club starts losing attendance)

Chapter 2 (Shimmer City and Dimmer City)

Dark World: Alphys’s Lab

Two distinct sections: Shimmer City (Alphys’s Main Lab) and Dimmer City (The True Lab). After PAUS open the Dark World, Flowey opens the elevator door to the True Lab, causing the Dark World to expand to that area.

Shimmer City: Retro Anime/Cyber Themed. Similar to Cyber City but with a bit more natural foliage and generally more lighthearted and inviting. More shojou and magical girl inspirations

Dimmer City: Retro Anime/Cyber Themed. Takes more inspiration from mecha, horror, and thriller anime.

Sublocations:

Shimmer Field (Starting Location)

Shimmer City (First City)

Watchtower (Veilance’s Tower)

Garbage Zone (Near the Watchtower and Dimmer City)

Dimmer City (Second City)

Spamelia and Co. Law Offices (Spamelia’s Shop located in Dimmer City)

Powerplant

Story Events:

PAUS/The Skeleton Crew go to Alphys’s Lab for the second Dark Worlds test

Sans has both Kia and Rubble in his inventory

Alphys talks about what Undyne has been doing as her lab assistant and its very cute

They open the Dark World which both Mad Mew Mew and Flowey watch happen

The crew wakes up in Shimmer City and eventually come across some Plugboys who immediately greet Alphys and tell her that the Watchtower has been malfunctioning since the Dark Fountain was made, and that she should go fix it before Shimmer City’s security systems start malfunctioning.

Early on they encounter Engar (Undyne’s Broadsword) who challenges them to a friendly sparring match but Undyne accidentally throws a spear into a wall which causes Veilance to show up

Veilance is in a panic, talking about how the walls between Shimmer City and Dimmer City are falling apart and threatens to capture Papyrus and Undyne to “protect Alphys”.

Undyne takes this as the threat it is and tries to start a fight against Veilance who flees and says that they will initiate an emergency lockdown if they Lightners don’t willingly meet them at the Watchtower.

Outside the Watchtower, PAUS/The Skeleton Crew are stopped by Mad Mew Mew who demands to have a fight with Undyne. Sans and Papyrus realize that they never told Alphys that her Mew Mew Doll was possessed by the ghost previously possessing Undyne’s training dummy.

During the fight, Undyne says something about having to help Alphys no matter what which sets Mad Mew Mew off and leads her to use an attack that knocks the party towards the Garbage Zone.

Noticing the fight, Veilance initiates the emergency lockdown, shutting the party in on the Dimmer City side of the Dark World.

On the way through the dump, Alphys and Undyne reminisce about their first meeting in Waterfall

Arriving in Dimmer City proper, the party visits Spamelia’s office who is very surprised to see Alphys visit Dimmer City

Spamelia explains that there’s bypasses for Veilance’s lockdown by going to the Powerplant and shutting off everything to go on back up power. However, the way is very dangerous as all the Dimmer City Darkners are supposed to capture the Lightners and take them for “extraction”.

Eventually, the party makes it to the Powerplant and shut down the main power, but on the way out their chased by Deedee (DT Extractor) through the darkness

Once their close enough to Shimmer City, Alphys recognizes what it is and helps calm it down, while promising to explain what it is to Undyne and the others later.

Swinging back by Spamelia’s, they see that Mad Mew Mew has calmed down and is just hanging out with Spamelia

Mad Mew Mew: “-I’ve put myself through so much for Undyne! I know that doesn’t mean she OWES me anything , but it just makes so mad, mad, MAD!!!” shreds up a stack of papers in Spamelia’s office

Spamelia: “Oh, [trust me], I get it, sister!” sips her coffee

Spamelia: (This girl is doing a better job then my paper shredder!)

The party makes it back to the Watchtower entrance. Spamelia starts sending messages to Alphys about how scary shit from Dimmer City may be trying to follow them inside to the Fountain

In the Watchtower lobby they’re immediately stopped by a locked door, but Kia hops out of Sans’s pocket and opens it for them

Kia: “This has already gone on long enough, let’s just get to good part already!”

Miniboss fight against a prototype for Mettaton’s old robot body (box form)

The party makes it to the top where Veilance is waiting for them, cue boss fight and they win

The Darkners coming from Dimmer City fuse into a giant Kaiju but Alphys comes up with a plan to turn all the Watchtower’s surveillance camera into a lazer. All the recruits and Mew Mew show up to help out. The gang has a shoot’em up boss fight and they win.

Undyne: “Hey, wait why is Sans weirdly good at aiming these things.”

Sans: “it’s all just comedic timing.” shrugs

The party seals the Dark Fountain and comes to back in Alphys’s lab. Alphys immediately panics when she sees that the elevator to the True Lab is open and runs to close it.

Undyne initially asks Alphys about whats up with the True Lab, which causes Alphys to panic so Undyne backs off and tells her not to worry about it right now.

Alphys then gets a text from Mettaton who has just invited everyone to come meet him for dinner at the MTT Resort

Intermission 2 (MTT Resort)

Story Events

Alphys, Undyne, Papyrus, Sans and Mettaton meet up and have dinner where they catchup on what everyone’s been up to

Mettaton quickly believes what everyone says about the Dark Worlds but wants to see it for himself so he requests Alphys to try the machine near his old house next time

On the way out, they bump into Dess who was painting graffiti outside the hotel of everyman cryptid. They have a lighthearted mock battle about it.

Chapter 1 (The Sea of Silver and Gold)

Dark World: Sans and Papyrus’s House

Pirate-themed because of Papyrus’s Jolly Roger flag and general skeleton imagery

Sub Locations:

Silver Shores (Sans’s Lab, starting location)

The Golden Isles (General Dark World)

The Crimson Cruiser (The Milkbone Pirate’s Ship/Papyrus’s Racecar Bed)

The Socket (The cove where Kia’s ship is anchored next to the Dark Fountain)

The Tidetreader (Kia’s Pirate Ship/Sans’s treadmill)

Kia: “The truth is you got owned, landlubbers!”

Sand Dollar Casino (Dog Shrine/Dog Casino)

Story Events

Alphys, Sans, Papyrus, and Undyne all meet up at the Skelebros house and boot up Sans’s machine with the DT Serum, creating a Dark World

Alphys, Papyrus, and Undyne wake up separate from Sans and immediately set off to go find him

Sans woke up earlier and was immediately greeted by Kia (Sans’s Silver Key) who convinced him to use his shortcuts to more quickly traverse the Dark World.

Pap, Undyne and Alphys run into the Milkbone Pirates and Undyne immediately tries to fight them until Papyrus reminds her of Toriel’s nonviolence policy.

The Milkbone Pirates tell PUA about the Dark Fountain and the old sea shantys that warn of the Dark Fountain’s potential to flood the whole world in darkness

The Milkbone Pirates also explain that Kia has a dangerous fascination with the Dark Fountain, wanting to use it for some experiment to “change her own fate”.

PUA boards the Crimson Cruiser and go island hopping so they stop Kia, and hopefully find Sans.

Pirate shenanigans, the Basockslisk miniboss encounter.

At some point, Alphys probably digs through her satchel and pulls out an “Odd Letter” hinting that Spamelia is technically present.

Kia explains to Sans that she wants to help him break the Barrier and admonishes him for giving up on his original goal of “going back” and generally squandering his many talents

The Milkbone pirates encounter Kia’s underlings and get shipwrecked near the Socket. From there, PUA go on foot towards Kia’s ship following Rubble.

Sans manages to slip away from Kia and re-joins Papyrus, Alphys, and Undyne, who were led to him by Rubble

“in-game”, Sans still has 1 HP so he automatically dodges any bullets until he’s the last party member standing

PUAS (and Rubble) go on the ship and eventually reach Kia. They fight and they win!

After the battle, Kia confesses that she doesn’t want to destroy the World or anything, but she instead tries to convince Sans to promise that he’ll keep experimenting with the Dark Worlds until they find a way to turn their dreams of breaking the Barrier into a reality.

Sans: “you know i don’t make promises anymore…but i’ll think about it.”

Then they seal the Fountain and come to in Sans’s very disorganized and chaotic room.

Sans recieves a call from Toriel asking how the experiment went

Intermission 1 (New Home)

PUAS go to New Home to report to Toriel

Toriel is teaching her class at the new school, so PUAS reports to Carol first. Would it surprise you to hear that Carol is very cold towards the band of misfits and is the straightman of this scenario

class is dismissed and Undyne benchpresses 7 children

Alphys and Sans tell her that the experiment worked, but don’t know how to tell her that they also potentially created a portal to a different plane of reality in the process.