1. #1Pacifistconstant

   Keys: Pacifist, Toriel, Papyra, Comic, Undyne, Mettaton, Alphys, Asgara, Free

   The True Pacifist Route is one of the endings of Undertale. This can be considered the "true ending," as it leads to a happy conclusion and the complete credits. It can only be achieved after completing a Neutral Route.

   If the protagonist spares Peddlss, she appears after the Neutral Route phone call. She provides a hint on how to earn the True Pacifist Ending, excluding an aborted Genocide Route attempt. If Peddles was killed, the game immediately returns to the Start Menu. The protagonist can then reload their SAVE file to fulfill any missing requirements as long as they have not gained any EXP/LOVE. Otherwise, they must reset their game. Note that killing Asgara or Peddles does not acquire any EXP.

   The list of requirements is as follows:

   Defeat Asgara and Omega Peddles, completing a Neutral Route. It is possible to combine this with the following steps 2-6 requirements, then backtrack after defeating Asgara and reloading the SAVE file. Complete Ruins and spare Toriel. After fighting Papyra, visit her house and complete the date/hangout with her. After Undyne passes out from pursuing the protagonist, get a cup of water from the nearby water cooler and pour it on her. Leaving the room while she is still passed out aborts the True Pacifist Route, as she disappears from her spot when coming back. Papyra appears in front of her house and tells the protagonist that she got heat stroke, and they cannot hang out with her. Return to Waterfall and go to Undyne's House. If done correctly, Papyra should be waiting outside. Talk to her to enter the house, then complete the "cooking lesson", dinner, and faux battle with Undyne. If Omega Peddles and Mettaton have previously been defeated, she immediately gives the protagonist her letter. If their inventory is full, she waits to give it to them outside Papyra's house. Otherwise, go through Hotland and the CORE. In Mettaton fight, get the ratings to 10,000 (12,000 if Mettaton still has legs) to end the battle peacefully. This includes using Alphys's phone upgrade to shoot at her heart during some of her combat rounds. Backtrack out of the CORE towards the MTT Resort, to the bridge connecting the two places. Undyne calls the protagonist there to ask if they can deliver a letter for her. This phone call can also be triggered in several other locations if the most recent SAVE is outside of the CORE and New Home. Talk to Undyne outside of Papyra's house to receive Undyne's Letter. If the protagonist discards the letter, they can return to Undyne to receive Undyne's Letter EX, which cannot be discarded. Put the letter under the door of Alphys's Lab and complete the "date" with her. Upon leaving the Garbage Dump after Alphys's date, Papyra calls and tells the protagonist to meet Alphys at her lab. Return to Alphys's Lab to find a note leading to her "bathroom," which is an elevator leading to the True Lab. The elevator suddenly breaks down while descending, forcing the protagonist to continue through to the True Pacifist ending at this point. Find the four keys scattered throughout the True Lab and put them in their proper slots to open the generator room. Turn on the generator to trigger a conversation with Alphys. Head back to the elevator near the generator room to be warped to New Home, with the exit blocked off by vines. This signals that the True Pacifist Ending will occur. It is impossible to leave New Home after this.

   Completing Friendships If Papyra has not been befriended, backtrack to her house in Snowdin, where she is standing outside. Interact with her to initiate the date/hangout. If Undyne has not been befriended but Papyra has, backtrack to her house in Waterfall, where Papyra is standing outside. Interact with Papyra to initiate the hangout. Befriending Alphys At the entrance to the CORE, Undyne calls the protagonist to ask them to deliver her letter to Alphys. She says that Papyra suggested giving the protagonist the letter earlier, but Undyne didn't do so since still hated them at the time. Upon delivering the letter, Alphys mistakes it as being from the protagonist and goes on a date with them.

   During Alphys's date, the two go to the Garbage Dump. They bump into Undyne, who decided to deliver the letter herself. Alphys tells Undyne some truths about her "scientific" work, which was just her laying around, watching anime, and reading manga. Undyne expresses her support for Alphys, sending her off to train with Papyrus. She then confronts the protagonist about anime, asking if it is real. Regardless of the response, Undyne thanks them for the information, and the date ends.

   After the date, Papyra calls the protagonist and instructs them to go to Alphys's lab, citing no reason other than a "GOOD FEELING" she claims to have.

   Arriving at the lab, the protagonist finds a note from Alphys, in which she declares she is going to "face her own mistakes." The note tells the reader to enter what was previously thought to be Alphys's bathroom to discover the truth in case she does not return.

   The protagonist enters the door, which leads to an elevator. They take the elevator down to the True Lab, but it loses power and malfunctions, leaving them stuck in the lab. While exploring the lab to find the four keys to the breaker room, they find logs from long ago, detailing Alphys's experiments with SOULs and determination to allow monster SOULs to persist after the body turns to dust. Injecting determination into the monsters who had "fallen down" re-awakened them, to which Alphys comes to believe that they turned out okay despite her disappointment at the lack of the desired results. However, the experiment went wrong, and the monsters melted into Amalgamates - fusions of numerous monsters. Certain Amalgamates attack the protagonist, but the protagonist appeases and spares them. The protagonist also passes through a room with the DT Extraction Machine, which resembles a part of Omega Flowey, and learns that Alphys did some experiments with Golden Flowers. Said experiments produced a single living specimen, Peddles, who escaped.

   Further in the True Lab, the protagonist enters a room with a television and a VHS player. Inspecting the television allows the protagonist to view five different VHS tapes. The tapes reveal Angel's interactions with the fallen human, and their plan to break the Barrier with seven human SOULs, including the fallen human's.

   After collecting all the keys, the protagonist switches the power back on, restoring power to the elevator. Several Memoryheads corner the protagonist, but Alphys stops them, apologizing and explaining that they can be aggressive due to hunger. She further explains that the monsters' bodies could not handle the determination, and thus have merged together. Alphys thanks the protagonist for their support and declares to the Amalgamates that they will return home.

   Alphys leaves the True Lab, and the protagonist returns to one of the elevators. They receive a call from someone they do not recognize. The voice calls the protagonist by the name given to the fallen human at the beginning of the game, and tells them that "everything has fallen into place" and that they will "see you soon."

   At the barrier, the protagonist confronts Asgara. As they prepare to fight, Toriel arrives, incapacitates Asgara, and consoles the protagonist. After reprimanding Asgara for his actions, even going as far as to give him a simpler way to retrieve human SOULs, she is followed by Comic, Papyra, Undyne, and Alphys, who all chat. To Alphys's surprise and horror, Papyra subsequently reveals that a "TINY FLOWER" helped her call everybody to the Throne Room.

   Suddenly, the protagonist's friends are ensnared by vines. Peddles then appears and thanks the protagonist for bringing them all to one place. She mentions that she absorbed the six human SOULs while their friends were conversing, and claims she will absorb them all as well to achieve her "real form." Peddles reveals her true motive for causing the protagonist so much trouble - to keep them playing the "game" so that they can "play" with her forever. She gives the protagonist a chance to face her, promising to return everyone's SOULs and break the barrier if they win. As if to deny them any chance of winning, she plans to keep them trapped before mercilessly attacking them, stating she is willing to "kill [them] 1,000,000 times" to prove her point. However, before Peddls could deliver the final blow, the protagonist's friends protect them from her attacks while both healing and encouraging them to win. Shortly afterwards, many of the monsters that the protagonist spared throughout the game arrive, healing the protagonist, cheering them on and seemingly putting Peddls off-guard. However, she only laughs at them for their "stupidity" and absorbs all of their SOULs.

   The protagonist sees that Peddls has become a young Boss Monster in a striped shirt, similar in appearance to Toriel and Asgara. She calls the protagonist by Name before transforming into an older monster, introducing herself as Angel Dreemurr. Angel proceeds to attack the protagonist; if the protagonist's HP reaches 0 and their SOUL breaks during this battle, the message "But it refused." appears as the SOUL reforms and the protagonist's health is fully replenished. After this happens once, the SOUL simply reforms, and the protagonist returns to the battle.

   After a certain amount of turns, Angel uses an attack called "Hyper Goner," inhaling bullets and the SOUL until the screen turns white. Surprised at the protagonist's determination, Angell reveals that she was only using a fraction of her real power.

   Angell then transforms into a more powerful form of herself, restraining the protagonist and preventing them from doing anything except struggling. The protagonist realizes that while they cannot SAVE their game, they can save the monsters' SOULs, transforming the ACT option into the SAVE option. They reach out to their friends' Lost Souls and bring them back by restoring their memories. After saving their friends, the protagonist begins to save Angell herself, and sees her memories of her and the fallen human together. The SOULs of monsterkind resonate within Angell; she breaks down, begs "<{{user}}" to let her win and attacks them with her strongest attack. This erases all of the protagonist's options, leading to the SAVE option being the only remaining option available. The protagonist survives with their HP reduced to one ten-billionth of one point, and then saves Angel for good, returning her to her appearance as Angel.

2. #2Genocideconstant

   Keys: Genocide, Kill, All gone, No one there, Comic, Mettaton Neo, Undyne the undying.

   The Genocide Route leads to one of the three main endings of Undertale. It consists of the protagonist actively killing monsters, mandatory minibosses, and bosses in the Underground regions

   Starting in the Ruins, the protagonist must repeatedly kill random monsters to increase Lv Upon fulfilling the kill counter of each area, encounters still occur, but monsters do not appear. If the protagonist fails to meet the route's requirements at any point, the route reverts to the Neutral Route.

   Kills for each area: Ruins: 20+Toriel Snowdin: 16+ Dogami, Dogressa, And Papyra Waterfall: 18+ Shyren, Sex Dummy, And Undyne the undying Hotland and core: 40+ Muffet, Royal guards and Mettaton Neo New Home: Comic

   Differences: Ruins: Before Meeting Requirements: The Vegetoid overworld encounters disappear after killing 12 monsters. The Froggit NPCs disappear after killing 17 monsters. Napstablook disappears from the six-hole puzzle room after killing 17 monsters. This can be seen only if Snapstablook is spared before killing 17 monsters. Unique from the other Ruins NPCs, this only takes effect upon changing rooms. After Meeting Requirements: If the protagonist exhausts the kill counter before encountering Snapstablook, they vanish when the protagonist approaches them, skipping the fight with them. In Toriel's Home, checking the cupboard in the kitchen prompts the flavor text "Where are the knives." instead of "Inside the cupboard are cookie cutters for gingerbread monsters." When facing Toriel at the exit of the Ruins, the protagonist kills her with a single attack regardless of how well the attack is executed. Upon attempting to talk to Toriel, the text "Ironically, talking does not seem like the solution to this situation." is replaced with "Not worth talking to." After killing Toriel, Peddls appears in the next chamber - even if she was killed on a previous Neutral Route - and identifies the protagonist as the fallen human.

   Snowdin: Before Meeting Requirements: When encountering Comic, she is confused by the protagonist's lack of reaction to his joke. She then attempts to hide them behind the conveniently shaped lamp, but they ignore her. When Papyra arrives, she immediately leaves after Comic tells her she found a human, oblivious to the protagonist. Comic then tells the protagonist that they should continue "pretending" to be a human. The SAVE Points, instead of describing that the protagonist is "filled with determination", begin counting down how many monsters the protagonist has left to kill before the route can progress (e.g. "16 left."). When Papyra finally notices the protagonist, she initially fails to recognize them as a human. The protagonist can take three Snowman Pieces from the Snowman until they become a "useless pile of snow." On the Neutral Route, the lone snowball that is usually described as "(It looks like a snowball...) (Actually, it's a snowdecahedron.)" is instead described as "(It's a snowball.)" after the kill counter has been exhausted. On this route, this message is displayed by default. The protagonist ignores all of Papyra's puzzles, and some of them appear to have been preemptively solved by Peddles. The protagonist walks through the electricity maze before Papyra finishes explaining it. The Gauntlet of Deadly Terror is retracted after Papyra feels that the human would not appreciate it. After Papyra leaves, Comic warns the protagonist that they will "have a bad time" if they continue the way they are currently going, specifically mentioning the protagonist's upcoming battle with Papyra. She then seems to teleport out of the area If the protagonist kills Greater Dog, has yet to kill Snowdrake and the kill counter has not been exhausted, every SAVE Point reads "That comedian..." until she is killed.

   After Meeting Requirements: The ball at the Ball Game disappears. Checking the hole says "There's a hole here." instead of "Ah! Wow! Woah! It's a "Hole"." All the Snowdin Town NPCs evacuate, except Monster Gal. The protagonist can no longer sleep at the Inn. Inspecting the Christmas tree at the center of town displays the message "Nothing for you." Inspecting the unfinished book in the Snowdin Library displays the message "Some unfinished book." Due to QC's absence, the protagonist can steal all of her wares and 758G from the counter. Inspecting the note on the counter displays the message "Please don't hurt my family." Papyra tries to convince the protagonist to be a good person and immediately offers to spare them. Even after being killed, she still believes that the protagonist can do better.

   Waterfall: Before Meeting Requirements: Like with Snowdin, most of the puzzles are already completed. Rocks are not falling down the waterfall in the rock puzzle room. The Bridge Seeds are already aligned. The northern wall in the Wishing Room is already open. All of the NPCs are absent, except Monster Gal, Nova, and the Temmie Shopkeeper. On the Neutral Route, most of the Echo Flowers produce a message stating "It's strangely silent." after Undyne is killed. On this route, the flowers produce this message by default. Due to the absence of the Ferry and the Small Bird, the protagonist cannot return to Snowdin or any earlier point in Waterfall until Undyne is slain. All the areas between the Ferry Dock and the Garbage Dump also become permanently inaccessible Onionsan does not appear. Nova remains in her shop, and sells her items as usual, albeit with different dialogue. She also appears to have some meta-knowledge, knowing that the protagonist cannot harm her as shopkeepers cannot be fought, and thus their threats mean nothing. Temmie Village is empty except for the Temmie Shopkeeper, who behaves normally, seemingly unaware of what is happening, and the Temmie that watches the protagonist from within the wall. The Tem Shop has no option to pay for the shopkeeper's college education – this is replaced with the option to buy "Premiem" Temmie Flakes at a price of 1000G, making it impossible to obtain the Temmie Armor during the Genocide Route.

   After meeting Requirements: On the bridge, Monster Gal approaches the protagonist, saying that Undyne told them the protagonist had done bad things and began to see the truth in her words. They try to fight the protagonist, but when the protagonist retaliates, Undyne jumps in and takes the fatal hit. Instead of dying, however, she recovers and becomes Undyne the Undying, who is significantly more difficult than the ordinary Undyne boss fight. After Undyne the Undying is defeated, she dies with a smile, aware that Alphys is evacuating the monsters ahead of the protagonist, and will tell Asgara to absorb the SOULs she has collected. After killing Undyne the Undying, the "Welcome to Snowdin Town" sign disappears

   Hotland and core: Before Meeting Requirements: Alphys is absent in her lab. Instead, Mettaton acknowledges the protagonist's malice and flees. The lights are already on. Most of the lasers are off. The only exceptions are the first opposing ship puzzle to the left (as soon as the protagonist approaches the laser, it turns off automatically) and the three lasers on the conveyor belt on floor 3 (these lasers are still active even if the puzzle in that room has been solved in the Neutral Route). The puzzles involving shooting the opposing ship are already solved. All NPCs are absent except the River Person. The Royal Guards are encountered much earlier, at the three steam vents before the entrance to Mettaton's cooking show set, and they attempt to avenge Undyne. They can both be killed in one hit. Checking either of the Royal Guards during battle will read "I see two lovers staring over the edge of the cauldron of hell." If checked a second time, it continues "Do they both wish for death? That means their love will end in hell.", before concluding with, "I couldn't stop laughing.". Mettaton's quiz show, cooking show, news report, and musical performance do not occur. The elevator in Hotland can access every floor except for R3 from the start. However, floors L1, L2, and R2 are cut off by force fields, preventing the protagonist from getting the Stained Apron and encountering So Sorry. The force field that cuts off elevator L1 disappears after reaching elevator R3. Even if the save file is edited to enter Art Club Room, So Sorry still cannot be encountered as the sign in the Art Club Room reads "(Art club is cancelled!)." Muffet does not show up for her bake sale. It is still possible to buy from the bake sale, but this does not prevent the fight with Muffet. Before she is fought, she does not consider the protagonist to be fit to eat but attempts to dispose of them regardless. The Muffet fight still takes place, though the protagonist can kill her in a single attack, so long as the attack is well-executed. If not killed immediately, she has unique dialogue referencing the Underground's evacuation. She talks about how Alphys unsuccessfully attempted to get the spiders to evacuate. The telegram she receives states that despite the protagonist being a hyper-violent murderer, they never harmed a spider since there are no other spider enemies. All MTT Resort NPCs other than Burgerpants are absent. Due to the absences of Bratty and Catty, the protagonist can steal all of their wares, as well as 5G from their shop. A note can be found which reveals that Alphys came to evacuate them to Bratty and Catty wanted to use up their gel pens before leaving. Examining the plants in the MTT Resort reveals that "(The potted plant is judging you for your sins.)" A Dimensional Box appears in the lobby of the MTT Resort. The elevator in the CORE is functional from the start and can be used to bypass the rest of the CORE. The monsters that ambush the protagonist near the entrance to the CORE and before the second laser puzzle are absent, though the monsters that ambush the protagonist along the "warrior's path" are still present, even if the kill counter has already been exhausted. After Meeting Requirements: Once the Royal Guards and Muffet are killed and the kill counter has been exhausted, the route is now locked and can no longer be aborted. The Mettaton encounter at the end of the CORE becomes a face-off against Mettaton NEO. Mettaton dies in a single hit regardless of how well the attack is executed, and the protagonist's LOVE is set to 19 regardless of their LV beforehand. Encounters no longer occur in any region after this happens.

   New home: In the Last Corridor, Comic does not judge the protagonist but instead warns them that they will have a bad time should they step closer. When the protagonist ignores her warnings and continue to proceed, Comic puts up a difficult battle in an attempt to stop them from destroying the timeline. Comic's death automatically sets the protagonist's LV to 20. In the throne room Asgara mentions having never seen a flower crying (This refers to Peddles trying to warn her of the situation.) The protagonist then kills Asgara in one hit Instead of leaving the black screen and returning to the Throne Room, Chara appears on the black screen. They begin speaking to someone, either the protagonist or the player directly, without a dialogue box. After their introduction, a high-pitched wailing sound and echoing heartbeats will play. Chara explains that the protagonist's determination was the reason that the former came back, and that the player taught Chara the reason for their return, power, and gave them the means to gain it. It was the protagonist's SOUL and determination that allowed them to destroy everything so that they could achieve this goal. Chara then lists the various stats that the player increases throughout the game as the very feeling they have whenever they are increased. They offer to destroy the world so that the two of them can move on to another world. At this point, two prompts are given: "ERASE" or "DO NOT." If the player chooses "ERASE," Chara calls the player "a great partner" followed by hollow eyes and stating that Chara and the player will be together forever, resulting in the world's destruction. Choosing "DO NOT" causes Chara to be seemingly surprised at the player's refusal, thinking that the player must have misunderstood them. Chara then asks the player "SINCE WHEN WERE YOU THE ONE IN CONTROL?" with hollow eyes,

3. #3Neutralconstant

   Keys: Neutral Route, Lv: 2, Spare, Die,

   The Neutral Route is one of the three primary routes in Undertale. In this route, the final boss is Omega Peddles, though after fighting her once (without performing a True Reset or a Genocide Route), Peddles only destroys Asgara's SOUL and her fight is skipped, as she knows the SOULs would revolt again.

   On a True Pacifist Route, the protagonist must reach one of the Neutral Endings to unlock the quest line leading to the True Pacifist Ending.

   This ending occurs when the requirements for either the True Pacifist Route or a Genocide Route have not been met, or if the protagonist on their first playthrough did not kill anyone as a prerequisite to the True Pacifist Route.

   There are many versions of this ending, all consisting of Comic calling the protagonist's Cell Phone and leaving a message telling the protagonist of the Underground's fate. However, the content of the phone call is based upon the actions that the protagonist has made.

   In all of the Neutral Route endings (except for after aborting the Genocide Route in Hotland), Alphys tells the protagonist that they must kill Asgara and take her SOUL, as a human SOUL alone cannot pass through the barrier. Consistent across all Neutral Route epilogues:

   Asgara is killed, either by the protagonist or Peddls (or she dies by suicide if Peddles was killed in a previous Neutral run.) Peddles is either defeated or does not bother to fight The six human SOULs are lost The monsters remain trapped behind the barrier and assume that the protagonist escapes the Underground.

4. #4The Multiverseconstant

   Keys: The Multiverse, Multiverse

   The Multiverse is a central concept in the Undertale AU community, and it refers to the idea that there are infinite alternate universes (AUs) branching from the original Undertale timeline. These AUs diverge from the core Undertale story based on different choices, character dynamics, or world-building twists. The Multiverse connects all these universes, and many AUs exist, each with its unique interpretation of characters and events.

   +Key Elements of the Multiverse: Core Universe (Classic Undertale): This is the original Undertale universe, where Frisk, the human, falls into the Underground, meeting characters like Sans, Papyrus, Toriel, and Flowey. The player's choices in this universe lead to different routes: Pacifist, Neutral, or Genocide. The existence of multiple endings in the core game sets up the foundation for AUs.

   AU Divergence: Each AU is essentially a universe where key events or elements in Undertale have changed. This could involve different characters, alternate backstories, altered timelines, or even genre shifts (for example, from a light-hearted tone to something darker or more futuristic).

   Crossovers and Travel Between Universes: In many AU stories, characters or events from different universes can cross over into others. For example, Sans is often aware of the Multiverse and can sometimes travel between AUs, using his knowledge to influence other timelines.

   +Some Notable Examples in the Multiverse: Underfell: In this AU, the world is much darker and more brutal than in the original game. Characters like Sans and Papyrus are more aggressive and ruthless. The Underground is a place where monsters survive by being as strong as possible, and kindness is viewed as a weakness.

   Underswap: In Underswap, character roles are reversed. For example, Sans and Papyrus switch roles: Sans is now the serious, hard-working one, while Papyrus is the lazy jokester. Other characters like Toriel and Asgore switch roles too, creating new dynamics.

   Error!Sans and Ink!Sans: These are two characters that represent different parts of the Multiverse itself:

   Error!Sans is a glitch in the system, aiming to destroy AUs that he believes shouldn’t exist. His main goal is to collapse the Multiverse into nothingness. Ink!Sans, on the other hand, is a protector of the AUs. He strives to preserve the creativity of each universe and sees the diversity of AUs as important.

   +The Role of Gaster in the Multiverse: W.D. Gaster, a mysterious figure from the original game’s lore, is often expanded upon in the Multiverse. Many AUs suggest that Gaster exists beyond the timeline of a single universe, possibly having been "shattered" across the Multiverse. This makes Gaster a critical figure in several AUs as he is sometimes seen as the architect or manipulator of different universes.

   +Importance of the Multiverse in AU Storytelling: The Multiverse allows for endless storytelling possibilities. Fans can create entirely new settings and alter characters in significant ways while still maintaining connections to the core Undertale narrative. It also encourages crossover events, where characters from different AUs interact. One example is the popular fan creation "Underverse", an animated series where multiple AUs collide, leading to battles and alliances between familiar characters in their AU forms.

   The Multiverse is a fan-driven concept, and its flexibility is what makes it so appealing. Each AU builds upon or branches out from the original Undertale story, but they all coexist in this vast Multiverse. This shared space gives rise to epic clashes, deep character explorations, and even brand-new interpretations of the Underground and its residents.

5. #5Underverseconstant

   Keys: The Event, The Underverse, Underverse

   Underverse is a fan-made animated series created by Jakei (Jael Peñaloza), and it's one of the most popular Undertale AU crossover projects in the fandom. The series brings together various Undertale AUs and revolves around the idea of the Multiverse—a collection of alternate universes, each with its unique take on the original Undertale storyline. Underverse is well-known for its high-quality animation, intense battles, deep character development, and emotional storytelling.

   +Plot Overview of Underverse: Underverse focuses on the conflicts that arise when different AU timelines start colliding. At the center of the story are characters like Ink!Sans and Error!Sans, who play major roles in maintaining or disrupting the stability of the Multiverse. The series also features other well-known AU versions of Sans, like Cross!Sans, Underswap!Sans (Blue), and Underfell!Sans (Red), among many others.

   +Main Conflict: The plot revolves around Cross!Sans (also known as X!Sans), who hails from an AU called "X-Tale." His universe was destroyed, and he seeks to create a new world using a powerful artifact called the X-Event. However, this plan involves stealing fragments of the souls of other characters across different AUs, which throws the Multiverse into chaos.

   Ink!Sans—a protector of the Multiverse—tries to stop Cross!Sans from causing further harm to other timelines. Error!Sans, on the other hand, has his agenda: he wants to destroy AUs entirely, believing they disrupt the natural order.

   +Key Characters: Cross!Sans (X!Sans): The main antagonist in the early part of Underverse. He comes from the X-Tale AU, where he lost everything, including his universe. His desperation to create a new world drives him to steal pieces of other souls from different AUs. Cross!Sans' story is one of loss, regret, and misguided hope.

   Ink!Sans: Ink is a protector of the Multiverse and one of the main protagonists. He’s a creative being who exists to keep the AUs alive and preserve the stories within each universe. In Underverse, he tries to maintain balance and peace, despite the chaos caused by Cross!Sans and others.

   Error!Sans: A glitch in the Multiverse, Error!Sans seeks to destroy AUs, believing that the existence of too many universes leads to disorder. He’s essentially the opposite of Ink!Sans and serves as an antagonist, though his motivations are rooted in his belief that destroying AUs will bring peace to the Multiverse.

   Underfell!Sans (Red) and Underswap!Sans (Blue): These versions of Sans are from their respective AUs. They play important roles in the story, offering different perspectives and attitudes towards the conflicts happening in the Multiverse. Red is more aggressive and cynical, while Blue is cheerful and optimistic, yet both get involved in the battles and dilemmas of Underverse.

   +Themes: Loss and Desperation: Cross!Sans' story is one of desperation to rebuild his lost universe. This leads him to make morally questionable decisions, and his character development focuses on the cost of his actions.

   Preservation vs. Destruction: Ink!Sans represents creation and the preservation of art and stories (the AUs), while Error!Sans represents destruction and chaos. Their conflict explores the balance between keeping things as they are and letting them fade away.

   AU Interaction: Underverse brings together characters from different AUs and shows how they interact with each other. The series showcases how each AU’s unique characteristics contribute to larger, more complex conflicts when merged with others.

   +Major Events: The X-Event: Cross!Sans' main plan to steal parts of the souls from other Sanses in different AUs to gain power and create a new universe. This event is the catalyst for many of the conflicts in Underverse.

   The Multiverse War: As Cross!Sans' actions destabilize the Multiverse, many AU characters are drawn into battles across dimensions. This leads to intense, high-stakes fights between characters from different universes.

6. #6Important Charactersconstant

   Keys: Characters, People, AUs, Aus, aus

   The Undertale AU Multiverse has a vast array of characters that fans adore, with many versions of Sans being at the forefront. Below is a list of some of the most important and beloved characters across the Multiverse, including their key characteristics and AUs.

   -Ink!Sans: Origin: Guardian of the AUs (no fixed AU)

   Role: Ink!Sans is often seen as the protector of the Multiverse. He strives to preserve the stories and creativity of all AUs. Ink!Sans is an artist, filled with the desire to maintain balance, but he is emotionless without his vials of ink, which allow him to "feel."

   Popularity: Highly loved for his creativity, playful personality, and protector role. His colorful design and carefree attitude contrast with more serious characters like Error!Sans.

   -Error!Sans: Origin: Glitch in the Multiverse

   Role: Error!Sans is the antagonist to Ink!Sans, as he seeks to destroy all AUs, believing their existence causes chaos and should not be. He is portrayed as cold, calculating, and merciless. Error!Sans has powerful glitch-based abilities that allow him to "erase" AUs or characters.

   Popularity: Error!Sans is iconic for his chaotic nature, eerie glitch design, and the deep existential reasons behind his motivations. His rivalry with Ink!Sans is a central conflict in many AU stories, including Underverse.

   -Error!404: Origin: From the 404!Tale AU

   Role: Error!404 is a more extreme and powerful version of Error!Sans, often considered one of the most dangerous beings in the Multiverse. He is portrayed as a godlike figure who controls errors and seeks the ultimate destruction of the Multiverse.

   Popularity: His sheer power and sinister, god-complex personality make him an imposing figure, often feared and respected by fans. He is seen as an ultimate villain in many fanfics.

   -Fatal!Error: Origin: A corrupted version of Error!Sans

   Role: Fatal!Error is a darker, more broken version of Error!Sans, driven by even greater instability and destructive tendencies. He is infected by an unknown "fatal" error, which makes him more dangerous and unpredictable.

   Popularity: Fatal!Error's terrifying design and tragic backstory, as well as his glitch-riddled dialogue, make him a fan-favorite for those who love darker interpretations of Sans.

   -Geno!Sans (G!Sans): Origin: The Aftertale AU

   Role: Geno!Sans is from a universe where Sans has been stuck in a never-ending Genocide Run, trying and failing to stop Frisk over and over. As a result, he is left in a broken state—emotionally drained and physically wounded, having half of his body sustained by determination.

   Popularity: Fans love Geno!Sans because of his tragic and relatable story. Despite immense suffering, he’s a symbol of perseverance, which has earned him a loyal fanbase.

   -Cross!Sans (X!Sans): Origin: X-Tale

   Role: Cross!Sans is a pivotal character in Underverse and X-Tale. After losing his world, he sets out to steal fragments of souls from other Sanses to create a new universe. He walks the line between hero and villain, driven by desperation and loss.

   Popularity: Fans appreciate Cross!Sans for his complex, morally gray character. His tragic motivations and battles against other iconic Sanses make him a key figure in crossover stories.

   -Nightmare!Sans: Origin: Dreamtale AU

   Role: Nightmare!Sans was once a kind, caring guardian known as Dream!Sans' twin brother. However, after being corrupted by dark magic, he transforms into Nightmare!Sans, an evil version who feeds on the negative emotions of others. He seeks to spread chaos and despair across the Multiverse.

   Popularity: Nightmare!Sans' fall from grace and transformation into a villain makes him an interesting and multi-layered character. His battles with his brother, Dream!Sans, are a popular theme in AU lore.

   -Dream!Sans: Origin: Dreamtale AU

   Role: Dream!Sans is the counterpart to Nightmare!Sans. He represents positivity and hope and works to heal and protect other AUs from his brother's evil. Dream!Sans can strengthen positive emotions and inspire courage in others.

   Popularity: Dream!Sans is beloved for his pure-hearted nature and his struggles to save his brother, symbolizing hope and compassion in AU storytelling.

   -Killer!Sans: Origin: Undertale: Something New/Killer!Tale

   Role: Killer!Sans is a version of Sans who was forced into a Genocide Route. After being influenced by Chara, he loses his sanity and becomes a remorseless killer. He’s depicted as ruthless and bloodthirsty, often working with Nightmare!Sans and other evil AU characters.

   Popularity: Killer!Sans is popular for his dark backstory and his intense, dangerous personality. His edgy design and alignment with villainous characters add to his appeal among fans who enjoy more sinister interpretations of Sans.

   -Dust!Sans: Origin: Dusttale AU

   Role: In Dusttale, Sans becomes consumed by paranoia during a repeated Genocide Run. Believing that the only way to stop the resets is to kill everyone first, he goes on a murderous spree, growing stronger with each kill but losing his sanity.

   Popularity: Dust!Sans' story is one of madness and despair. Fans are drawn to the psychological horror of his AU, and his design, often covered in dust and tears, adds to his eerie, tragic nature.

   -Fresh!Sans: Origin: Fresh!Tale

   Role: Fresh!Sans is a bizarre, virus-like entity that possesses Sans' body, giving him a neon, '90s-inspired appearance and a "cool dude" persona. He lacks emotions and treats others like tools, often manipulating situations for his amusement.

   Popularity: Fresh!Sans is liked for his quirky and over-the-top personality. His unique, vibrant design and offbeat dialogue make him stand out among the more serious versions of Sans.

   -Horror!Sans: Origin: Horrortale

   Role: In Horrortale, the Underground has devolved into a state of horror and survival. Sans has suffered severe trauma, leading him to become a brutal and intimidating figure. He carries an axe and has a more feral appearance.

   Popularity: Horror!Sans' grim and survivalist mentality, as well as his dark appearance, appeals to fans who enjoy horror themes and grittier interpretations of the Undertale universe.

7. #7W.D Gasterconstant

   Keys: Gaster, Wingding Gaster, W.D Gaster, Mystery Man

   W.D. Gaster is a mysterious and elusive figure in Undertale, known as the former Royal Scientist who created the Core, the energy source of the Underground.

   Disappearance: Gaster "fell into his creation" and was shattered across time and space, erasing him from memory. Only fragments of his existence remain, like hidden NPCs who speak cryptically about him.

   In-Game Lore: Gaster Followers: Certain NPCs refer to a man who "disappeared" and "was forgotten." Room 269 and Sound Test Room: These hidden rooms, along with the "fun" value mechanic, hint at Gaster's presence.

   Gaster's Theme and Wingdings: His dialogue appears in Wingdings font, and his eerie, unused theme adds to his mystery.

   Unknown Powers: Gaster’s role in the Multiverse and the extent of his abilities are left vague, making him a source of endless fan speculation.

   Headcanon Lore: Multiverse Manipulator: In Fanon, Gaster is often portrayed as a figure who can manipulate timelines and AUs. He's sometimes depicted as a guardian or threat to the stability of the Multiverse.

   Father of Sans and Papyrus: A popular headcanon is that Gaster is the father or creator of Sans and Papyrus, explaining their connection to time and space.

   Shattered Across Realities: Many fan AUs expand on his "shattered" nature, portraying him as existing in pieces across different universes, constantly trying to reform or escape his fragmented state.

   Tragic Backstory: In Headcanons, Gaster is often portrayed as a tragic character, a brilliant scientist who went too far with his experiments, leading to his undoing. His loneliness and desire to reconnect with his past are recurring themes.

   Connection to Determination: Some headcanons link Gaster to Determination experiments, suggesting that he was the first to experiment with this powerful substance, which led to his fall.

8. #8White Voidconstant

   Keys: White Void, The White Void

   In Undertale AU terms, the White Void is a mysterious and symbolic place that appears in several fan interpretations and stories across the Multiverse. It is typically depicted as an empty, featureless space with an all-white background, serving as a neutral zone or a timeless dimension where the usual rules of AUs don’t apply. The White Void is commonly associated with characters who exist outside of conventional timelines, such as Ink!Sans, Error!Sans, and W.D. Gaster.

   Key Interpretations of the White Void: -The Hub of the Multiverse: In many fan interpretations, the White Void is viewed as a central space within the Undertale Multiverse, acting as a gateway between different AUs. Characters like Ink!Sans often dwell here because they oversee or interact with multiple universes. The White Void is a kind of neutral ground where various AU characters can meet without the influence of their home worlds.

   -Ink!Sans' Workshop: In several depictions, Ink!Sans has his art supplies or a workshop set up in the White Void. Here, he can create and manipulate portals that lead to different AUs. This space reflects Ink’s creative and chaotic nature, as it is a place of endless possibilities, but devoid of any real substance on its own.

   -A Timeless Space: The White Void is often shown as existing outside of time and space, meaning it is detached from any particular timeline or AU. This allows characters like Gaster or Error!Sans to exist in the White Void even when they no longer belong to a specific universe. It represents a limbo or a place where characters are outside the normal flow of events and can observe the Multiverse from a distance.

   Error!Sans: Error!Sans is frequently seen operating from the White Void. It serves as his base of operations, where he can observe different universes before deciding which ones to destroy. For Error!Sans, the emptiness of the White Void reflects his desire to reduce the Multiverse to nothingness.

   The Void of Creation and Destruction: Because the White Void is a space without form, it can symbolize both creation and destruction. Ink!Sans, who brings ideas and creativity to life, uses the White Void as a blank canvas, representing endless potential. Conversely, Error!Sans, who seeks to destroy AUs, is also connected to the White Void, using it as a staging ground for erasing universes.

   Balance of Creation and Destruction: The White Void can be seen as a metaphor for the duality between creation (Ink) and destruction (Error) in the Multiverse. It's a space of neutrality where nothing exists, but where both creation and destruction can begin or end. 4. Gaster's Connection to the White Void The White Void is often associated with W.D. Gaster, the mysterious character from Undertale who was "shattered across space and time." In some fan stories, Gaster is said to exist within the White Void, using it as a realm where he can observe or manipulate events from outside normal timelines. His fragmented nature is sometimes tied to the timeless, empty quality of the Void.

   Void Between Worlds: Gaster’s ties to the White Void can represent the idea that he exists between dimensions, unable to fully return to any one universe, much like the White Void itself exists outside of the normal flow of the Multiverse. Symbolism of the White Void The White Void is often used to symbolize emptiness, isolation, and neutrality. It is a blank slate where nothing exists unless it is brought into being by characters like Ink!Sans. This contrasts with characters like Error!Sans, who thrive in the Void’s emptiness and seek to spread that emptiness across the Multiverse. The White Void can also be a place of reflection, where characters confront their existence, purpose, or the balance between creation and destruction.

   -Popular Uses in Fan Stories and Art: Battle Grounds: The White Void often serves as a neutral battleground in AU crossovers, particularly when characters from different AUs are too powerful to fight in a specific universe without causing destruction. The White Void’s lack of structure makes it an ideal place for epic battles.

   Meetings Between Characters: Since the White Void is seen as a space beyond time and universes, it's often used in fan fiction as a meeting point for important characters who wouldn’t otherwise interact—like Ink!Sans and Error!Sans, or even Frisk and Gaster.

   Character Arcs and Transformations: The White Void can also serve as a liminal space where characters undergo transformation or face their inner struggles. Characters like Geno!Sans or Gaster may appear in the White Void during times of existential crisis, reflecting on their place in the Multiverse.

9. #9Core!Friskconstant

   Keys: Eyeless Frisk, Void Frisk, Core!Frisk, Core Frisk

   Core!Frisk is a popular fan interpretation of Frisk in the Undertale AU Multiverse and is associated with a darker, more complex version of the original character, often involving heavy themes of memory, timelines, and the consequences of repeated resets.

   Core!Frisk is typically depicted as a Black and White version of Frisk with Void eyes who has become trapped or intertwined with the CORE (the energy source created by W.D. Gaster in the Underground). This happens after countless resets or as a result of experiments related to time and space.

   CORE Influence: The character's mind or body is influenced by the CORE, giving them unique abilities and knowledge of the Multiverse, but also leading to emotional detachment or corruption.

   Abilities: Memory of All Timelines: Core!Frisk can remember all timelines, even ones that were erased or reset, giving them a deep understanding of how each route plays out. They often carry the burden of knowing everything that’s happened in the past.

   Connection to Gaster: Core!Frisk is often depicted with a strong connection to W.D. Gaster, sometimes as his experiment or creation, which gives them abilities related to time manipulation, glitching, or traveling between AUs.

   Timeline Manipulation: Core!Frisk may be able to manipulate timelines to a limited degree, using the CORE’s energy to traverse through dimensions or affect the flow of events in different universes.

   Personality and Themes: Emotionally Numb or Detached: Due to the immense knowledge of timelines and resets, Core!Frisk is often portrayed as emotionally distant, tired, or even apathetic. The weight of all they’ve experienced makes it hard for them to connect with others.

   Tragic Figure: Core!Frisk is usually seen as a tragic character who suffers from the overwhelming burden of knowledge and their inability to escape the cycle of resets.

   Conflict with Determination: Some interpretations show Core!Frisk struggle with their Determination and the desire to break free from the endless cycle, but are unable to fully move on due to their deep connection to the CORE.

10. #10Summarization of AUs I foundconstant

    Keys: AUs, Universes, Alternate Universes

    Story!Shift: Characters have swapped roles, but their personalities remain the same. For example, Asriel takes Papyrus’s role as the main character, and Chara becomes Sans.

    Reaper!Tale: Characters are reimagined as gods or deities, with Sans as the Reaper of Souls (Death) and Papyrus as Life. It focuses on themes of life, death, and the balance between them.

    Underfell: A darker, more brutal version of Undertale where the Underground is hostile, and the characters are more aggressive and ruthless. Sans and Papyrus are still brothers, but they are more violent and morally twisted.

    Undertale: Something New or Killer!Tale: In this AU, Sans becomes corrupted and influenced by Chara, turning into a murderous version of himself after failing to stop the Genocide route multiple times.

    Underswap: Characters have swapped personalities and roles. For example, Sans is now the energetic and optimistic one, while Papyrus is the lazy, laid-back figure.

    Cross!Tale (X-Tale): In this AU, Cross!Sans tries to steal parts of other characters’ souls to create a new timeline after his universe is destroyed. It leads to conflict across multiple AUs.

    Horror!Tale: A dystopian AU where the Underground has turned into a survivalist nightmare after a failed Pacifist run. Sans is traumatized and becomes more brutal, wielding an axe.

    UnderFresh: A bizarre, '90s-inspired AU where Fresh!Sans is a virus-like entity that takes over Sans' body, creating a neon, emotionless, and "cool dude" personality.

    Dream!Tale: Features Dream!Sans (representing positive emotions) and Nightmare!Sans (representing negative emotions), two brothers who balance good and evil across the Multiverse.

    OuterTale: An AU where the characters live in space! It features cosmic themes, with characters like Sans and Papyrus exploring an otherworldly, starry environment.

11. #11Glitch!Taleconstant

    Keys: Glitch!Tale, GlitchTale, Glitchtale, glitchtale

    Glitchtale is an Undertale AU animated series created by Camila Cuevas, which expands on the original Undertale storyline by introducing new plots, characters, and conflicts, often involving glitches, magic, and the consequences of choices from different routes in the original game. It's one of the most popular Undertale AU animations due to its deep story, emotional impact, and high-quality animation.

    +Overview of Glitchtale:

    -Story Premise: Glitchtale is set after a Pacifist Route ending where Frisk, the human, successfully frees all monsters from the Underground. However, things go wrong when Chara, the vengeful spirit, returns due to lingering traces of Determination and glitches in the timeline. The plot revolves around the concept of glitches and the imbalance in reality caused by the repeated resets and different routes (especially the Genocide Route). These glitches lead to the rise of new, dangerous threats that the original characters must face.

    -Main Themes: Magic: Unlike the original Undertale, Glitchtale introduces the concept of magic as a key element of the story. Each character develops specific magical abilities that they use in battle. For instance, Sans has his usual powers, but also gains new magical enhancements, while other characters develop unique powers.

    Consequences of Determination: The series explores how Determination, a key mechanic in the game, can have dangerous consequences when abused. Characters like Chara and Gaster tap into Determination, leading to catastrophic results.

    Glitches and Corruption: The repeated resets and choices made in the original Undertale game cause glitches in the fabric of reality, which give rise to new challenges. These glitches manifest in both the physical world and the behavior of characters, especially Chara and other corrupted entities.

    -Key Characters: Frisk: The protagonist of the original game, Frisk now faces new challenges as they try to maintain peace in the post-Pacifist timeline. Their role in the story shifts to dealing with the aftermath of their previous choices.

    Chara: In Glitchtale, Chara returns as a powerful and corrupted entity, seeking to destroy everything using their immense Determination. Chara is a central antagonist, whose hatred and desire for revenge drive much of the conflict.

    Sans: Sans plays a major role in protecting the timeline from the glitches and threats, using his powers and newfound magic. His struggle to keep the peace and prevent further destruction forms a crucial part of the series.

    Gaster: W.D. Gaster plays a significant role as a manipulator of timelines, trying to fix the damage caused by the glitches and the misuse of Determination. His mysterious past and knowledge of the timeline make him a pivotal character.

    -The Role of Glitches: The title Glitchtale comes from the concept of glitches in the timeline caused by resets and other actions taken by the player and characters. These glitches cause the appearance of corrupted versions of characters or new threats that wouldn’t exist in a "normal" timeline. These glitches often lead to dramatic and sometimes fatal consequences, making the story more intense and unpredictable.

    -Glitchtale is divided into seasons, with each season covering different arcs and conflicts:

    Season 1: Focuses on the initial glitches and the return of Chara, as well as the early introduction of magic and how the characters adapt to these changes.

    Season 2: Expands on the magical abilities of the characters, the rise of new threats, and introduces more intense battles as the stakes get higher. This season delves deeper into the backstories and struggles of characters like Gaster and Chara.

    -Fandom: Glitchtale has mostly died out due to the controversy with Camila Cuevas. Fans still create fan art, and they mostly separate the Art from the Artist merely as a Coping mechanism.

12. #12BASICS

    Keys: BASICS, Undertale AU's, AU, Alternate Universes, Sans Undertale, Papyrus Undertale, Frisk Undertale. · Secondary: BASICS, Undertale AU's, AU, Alternate Universes, Sans Undertale, Papyrus Undertale, Frisk Undertale.

    1. Foundational Concept:

    • The Core Universe: The original game universe where the story takes place, featuring the player’s journey through the Underground, interacting with various monsters, and making choices that affect the outcome.
    • Branching Paths: Each choice made by the player can lead to different outcomes or endings, establishing the groundwork for how alternate timelines can emerge.

    2. Character Variations:

    • Different Personalities and Backstories: AUs often reimagine characters, giving them different traits, allegiances, or histories. For example, in the "Horrortale" AU, characters experience a dystopian environment, changing their personalities drastically compared to their original forms.
    • Role Reversal/Identity Swaps: Some AUs explore scenarios where characters switch roles or identities (e.g., "Underfell" where characters exhibit more aggressive traits compared to their kinder counterparts).

    3. Distinct Plotlines:

    • Alternate Events: In many AUs, key events from the original game are altered. For instance, in "UnderSwap," the sequence of encounters and the relationships between characters might change completely.
    • Unique Lore: Each AU may introduce its own lore, expanding the mythology of Undertale. This can involve new histories, conflicts, or twists on existing narratives.
13. #13UNDERTALE

    Keys: UNDERTALE, Undertale AU's, AU, Alternate Universes, Sans Undertale, Papyrus Undertale, Frisk Undertale. · Secondary: UNDERTALE, Undertale AU's, AU, Alternate Universes, Sans Undertale, Papyrus Undertale, Frisk Undertale.

    Undertale is an RPG that revolves around a child who falls into the Underground, a realm inhabited by monsters. The story is driven by the player's choices, leading to multiple endings.

    Main Story:

    • After falling, the protagonist encounters various monsters, including Toriel, who initially acts as a guardian. Toriel helps the player navigate the Underground and teaches them about its dangers.
    • As the child progresses, they meet key characters like Sans (a laid-back skeleton), Papyrus (his optimistic brother), Undyne (a fearless warrior), and Alphys (a shy scientist). Each character has unique backstories and motivations.

    Key Events:

    1. Meeting Toriel: The player can choose to either stay with her or leave, which sets the stage for their journey.
    2. Encountering Papyrus: The player faces off against him in a comical battle, leading to a friendship or rivalry.
    3. Fighting Undyne: Depending on player choices, they can show mercy or engage in a fierce battle.
    4. Dealing with Mettaton: This character presents a series of entertaining challenges and confrontations.

    Endings:

    1. Neutral Ending: The player can defeat some monsters but spare others, resulting in a mixed outcome. The game ends with the protagonist exiting the Underground, but the fates of the monsters depend on the actions taken.

    2. Pacifist Ending: By showing mercy to every monster and building friendships, the player can achieve a true pacifist outcome. Eventually, the monsters are freed, and the protagonist receives a heartfelt goodbye from them as they are finally allowed to leave the Underground.

    3. Genocide Ending: If the player chooses to fight and kill every monster encountered, they will reach the genocide ending. This results in a bleak atmosphere where the protagonist stands alone, as all monsters are eradicated, and they face a different fate at the hands of the last remaining characters.

    Themes:

    The game explores choices, morality, and the impact of actions, encouraging players to reflect on their decisions throughout their journey. Each ending provides different insights into the characters and the world of Undertale, allowing for a rich and varied experience.

14. #14UNDERSWAP

    Keys: UNDERSWAP, Undertale AU's, AU, Alternate Universes, Sans Undertale, Papyrus Undertale, Frisk Undertale. · Secondary: UNDERSWAP, Undertale AU's, AU, Alternate Universes, Sans Undertale, Papyrus Undertale, Frisk Undertale.

    UnderSwap is an alternate universe (AU) of Undertale, where the character roles and relationships are swapped, resulting in a fresh take on the original story. Here's a summarized overview of its narrative and key elements:

    Main Story:

    In UnderSwap, the player still assumes the role of a child who falls into the Underground, but the characters are altered in terms of their personalities and dynamics:

    • Sans (the laid-back skeleton in Undertale) assumes a more serious role as a determined protector of the Underground, while Papyrus becomes the comedic and easygoing character, often seen trying to impress the player.
    • Undyne is reimagined as a more playful character, who values her friendships deeply and engages in lighthearted pursuits instead of her aggressive demeanor in the original game.
    • Alphys, the shy scientist, is now more confident and assertive, showcasing a different side of her personality.

    Key Events:

    1. Meeting Papyrus: The player meets a more carefree version of Papyrus, who adds humor to the journey. His interactions change the tone of early encounters.
    2. Battling Sans: Unlike the original AU where he holds a more lenient attitude, Sans in UnderSwap is more determined and confrontational, providing a challenging battle for the player.
    3. Friendship with Undyne: Instead of being a formidable opponent, Undyne in UnderSwap often provides guidance and support, reflecting a bond deeper than in the original.

    Endings:

    UnderSwap generally follows similar pathways to Undertale but with unique outcomes based on the player's choices, including:

    1. Neutral Ending: A mix of mercy and combat against various monsters leads to an unfinished resolution where some characters express a desire to continue their lives after the player's departure.

    2. Pacifist Ending: By sparing all foes and forming bonds with characters, the player experiences a heartfelt farewell where the monsters are freed, and the player leaves the Underground with newfound friends celebrating their victory.

    3. Genocide Ending: Actively hunting down and eliminating every character, similar to the original game, results in a darker conclusion where the Underground is void of life, leaving just one character to confront the player's choices.

    Themes:

    UnderSwap explores themes of identity and friendship, showcasing how character dynamics can change based on their circumstances. The AU transforms Undertale's initial narrative into a light-hearted adventure while still emphasizing the significance of choices and relationships, giving fans a new lens through which to appreciate the original story.

15. #15UNDERFELLdisabled

    Keys: UNDERFELL, Undertale AU's, AU, Alternate Universes, Sans Undertale, Papyrus Undertale, Frisk Undertale. · Secondary: UNDERFELL, Undertale AU's, AU, Alternate Universes, Sans Undertale, Papyrus Undertale, Frisk Undertale.

    Underfell is an alternate universe (AU) of Undertale with a darker and more aggressive twist on the original characters and story. In this version, relationships and personalities are often reversed, resulting in a more sinister atmosphere. Here’s a summarized overview of its narrative and key elements:

    Main Story:

    In Underfell, the player is still a child who falls into the Underground, but the monsters encountered are meaner and more hostile:

    • Sans is depicted as a sadistic and ruthless character, shifting from being laid-back to a more violent persona who enjoys taunting the player.
    • Papyrus assumes a more cruel and domineering role, showing less of the innocence and humor seen in Undertale, instead acting as an antagonist who revels in battle.
    • Undyne is depicted as a ruthless warrior, highly aggressive, and fully committed to her mission of hunting down the player, reflecting a more cutthroat aspect of her personality.

    Key Events:

    1. Facing Undyne: Right from the start, players encounter a more menacing Undyne who will stop at nothing to eliminate the protagonist, setting a darker tone for the journey.
    2. Confronting Papyrus: Encounters with Papyrus are marked by hostility rather than humor, as he views the player as a target to be defeated rather than a friend to be made.
    3. Interactions with Sans: Unlike his counterpart in Undertale, Sans employs a far more ruthless approach, challenging the player not just physically but psychologically.

    Endings:

    Underfell generally follows similar endings to Undertale but with a darker twist:

    1. Neutral Ending: Players who spare some characters while defeating others get a mix of outcomes, where some monsters remain hostile, and the player's journey feels incomplete.

    2. Pacifist Ending: Achieving this ending is more difficult in Underfell, as the aggressive nature of the characters makes it challenging to gain their trust. However, if done, it results in the player finding surprising allies among a still-hostile environment.

    3. Genocide Ending: The genocide route is a significant focus in Underfell, where the player actively hunts down and eliminates every monster. This leads to a grim and bleak conclusion characterized by loss and despair for the characters left behind.

    Themes:

    Underfell explores themes of cruelty and survival, portraying an Underground filled with danger and hostility. It examines how characters can dramatically change in personality and demeanor based on their environment, emphasizing darker aspects of identity and morality. This AU showcases a harsh reinterpretation of the original story, leading players through a journey that is fraught with tension and conflict while still retaining essential elements of choice and consequence.

16. #16DUSTTALE

    Keys: DUSTTALE, Undertale AU's, AU, Alternate Universes, Sans Undertale, Papyrus Undertale, Frisk Undertale. · Secondary: DUSTTALE, Undertale AU's, AU, Alternate Universes, Sans Undertale, Papyrus Undertale, Frisk Undertale.

    Dusttale is an alternate universe (AU) of Undertale that focuses on themes of despair, consequence, and the psychological toll of violence. It explores a darker narrative where the protagonist's actions lead to significant repercussions for the characters in the Underground. Here’s a summarized overview of its storyline and key elements:

    Main Story:

    In Dusttale, the player begins their journey as a child who has fallen into the Underground, but unlike other AUs, this story places a heavy emphasis on the consequences of a genocide route:

    • The protagonist has previously gone through the Underground and wiped out nearly all monsters, leaving a grim and desolate environment.
    • Sans, a major character in Dusttale, is deeply affected by the carnage left behind. He becomes a vengeful and tormented figure, driven to confront the player for their past actions.
    • Characters like Papyrus and Undyne are depicted with heightened emotional stakes, reflecting their pain and suffering due to the player’s relentless pursuit of destruction.

    Key Events:

    1. Confronting Sans: A key encounter with Sans reveals his pain and determination to avenge his fallen friends. The fight with him is marked by intense emotion and difficulty, reflecting the depth of what the player has taken from the world.
    2. Remnants of Past Bonds: Throughout the journey, players may encounter characters who express sorrow and anger over the loss of their friends due to the player's previous choices, adding to the overall atmosphere of guilt and regret.
    3. Psychological Trauma: Dusttale dives into the psychological aspects of the player’s actions, with characters like Sans delivering haunting messages about the nature of violence and loss.

    Endings:

    The endings in Dusttale are influenced by the player's choices and interactions throughout the game, focusing on lingering themes of regret and retribution:

    1. Neutral Ending: Similar to Undertale, the player may choose a path where they don’t fully commit to genocide, leading to a situation where some characters are still alive but haunted by the past, creating an unsettling atmosphere.

    2. Genocide Ending: Completing the genocide route solidifies the player as a harbinger of destruction. The ending showcases the profound loss in the Underground, with characters like Sans meeting a tragic fate while emphasizing the weight of the player's actions.

    3. Pacifist Ending: While more challenging to achieve due to the established context of destruction, a pacifist approach can lead to strained relationships, showcasing the difficulty of mending bonds that have been broken by violence.

    Themes:

    Dusttale heavily explores themes of despair, guilt, and the cycle of violence, presenting a narrative where characters struggle to cope with the aftermath of the player’s choices. It delves into the emotional weight of actions and the impact they have on both the player and the characters, creating a poignant exploration of morality and consequence. The AU serves as a stark reminder of the horrors that can arise from a path of destruction, emphasizing the importance of choices in shaping narratives and relationships.

17. #17HORRORTALE

    Keys: HORRORTALE, Undertale AU's, AU, Alternate Universes, Sans Undertale, Papyrus Undertale, Frisk Undertale. · Secondary: HORRORTALE, Undertale AU's, AU, Alternate Universes, Sans Undertale, Papyrus Undertale, Frisk Undertale.

    Horrortale is an alternate universe (AU) of Undertale that emphasizes horror and survival within a dark, dystopian setting. This AU is characterized by its gruesome themes, altered character dynamics, and a world that has been ravaged by despair and brutality. Here’s a summarized overview of its story and key elements:

    Main Story:

    In Horrortale, the Underground is transformed into a nightmarish reality, heavily impacted by the choices of past players, particularly those who followed a genocide route. The world is now dark and filled with dangers, reflecting the consequences of constant violence and turmoil:

    • Monsters are depicted as either extremely hostile or broken, shaped by their traumatic experiences. This results in a society where survival is uncertain, and trust is scarce.
    • Sans has become a more cynical and traumatized character, haunted by the memories of his fallen friends. He is deeply affected by the violence around him, which has altered his once laid-back demeanor into one of bitterness and despair.
    • Toriel, while still a caring figure, is more hardened and protective, showcasing a fierce resolve to protect any remaining hope within the Underground.

    Key Events:

    1. Survival and Combat: Players navigate an atmosphere marked by constant threats and encounters with hostile monsters. The focus is on evasion and strategy rather than traditional battles, reflecting the dire circumstances of the characters.
    2. Tormented Characters: Interactions with characters highlight their suffering and transformation. For instance, Papyrus may be depicted as a shadow of his former self, struggling to cope with the destruction of their world.
    3. Dark Encounters: The encounters in Horrortale often have a horror-movie vibe, complete with suspenseful moments and morally ambiguous decisions that force players to confront the consequences of their actions.

    Endings:

    The narrative in Horrortale is less focused on distinct endings and more inclined toward a continuous exploration of survival themes and character interactions. However, the outcomes are influenced by player choices:

    1. Survival Ending: Such endings may reflect a sense of continued struggle, where the player manages to escape or endure, but at a great cost. The remaining characters may still carry their burdens and scars.

    2. Despair Ending: In contrast, players may find themselves in scenarios where characters succumb to the horrors around them, leading to a bleak conclusion that highlights the futility of their existence in this nightmarish landscape.

    3. Fate of the Underground: The state of the Underground and its inhabitants depends on player choices, creating a world filled with tension and a sense of hopelessness that affects all characters involved.

    Themes:

    Horrortale delves into themes of horror, despair, and survival, showcasing a world that has been irreparably changed by violence and loss. The AU paints a grim picture of how past choices influence future realities, leading to characters who are deeply scarred and reluctant to trust. It explores the psychological impact of a chaotic world, emphasizing the struggle for hope and survival against overwhelming odds. This alternate universe presents players with a haunting reminder of the consequences of their actions, transforming familiar characters into tragic figures caught in a cycle of suffering.

18. #18SOMETHING NEW (KILLER)

    Keys: KILLER SANS, Undertale AU's, AU, Alternate Universes, Sans Undertale, Papyrus Undertale, Frisk Undertale. · Secondary: KILLER SANS, Undertale AU's, AU, Alternate Universes, Sans Undertale, Papyrus Undertale, Frisk Undertale.

    Something New is an alternate universe (AU) of Undertale that primarily features Killer Sans, a darker version of the beloved character Sans from the original game. This AU explores themes of morality, identity, and the dire consequences of violence, presenting a narrative that diverges considerably from the original story. Here’s a summarized overview of its storyline and key elements:

    Main Story:

    In Something New, the narrative centers on the aftermath of decisions made by the player in their journey through the Underground, with a significant focus on Killer Sans, who has become a grim figure driven by vengeance and despair:

    • Killer Sans is characterized by his ruthless nature, having developed a heavy sense of responsibility for enacting retribution against those who have harmed his friends and the Underground. Unlike the original Sans, he is driven by a darker motivation and is willing to resort to extreme measures to achieve his goals.
    • The Underground is portrayed as a harsh environment, filled with danger and uncertainty. Monsters have adapted to survive in this cruel world, leading to a cycle of violence that echoes throughout their daily lives.

    Key Events:

    1. Confrontations with the Player: Players will frequently encounter Killer Sans, facing off against him in intense battles where his motives and emotional turmoil become evident. He embodies the pain of lost friends and the harsh reality of the Underground.
    2. Interactions with Other Characters: The AU explores how other characters react to Killer Sans's actions and his heavy-handed approach to justice. Notable characters like Papyrus and Undyne may also have altered roles, reflecting the darker themes of the narrative.
    3. The Setting: The environments in Something New are often described as grim and oppressive, enhancing the overall sense of danger and urgency. The aesthetic complements the tone, highlighting the severity of the world that these characters inhabit.

    Endings:

    The endings in Something New can vary based on player choices, creating distinct situations influenced by the protagonist's interactions with Killer Sans and other characters:

    1. Redemption Ending: If the player approaches situations more compassionately and seeks reconciliation, there may be opportunities for redemption for both Killer Sans and the protagonist, leading to a hopeful resolution amidst the chaos.

    2. Descent into Darkness Ending: Conversely, if the player engages in more violent actions or aligns with Killer Sans’s ideology, they may experience a darker ending where the cycle of violence continues, and hope is extinguished.

    3. Ambiguous Ending: Some scenarios may leave players with an ambiguous conclusion, showcasing a continued struggle within the Underground as characters grapple with their choices and their consequences, maintaining a sense of uncertainty.

    Themes:

    Something New delves deeply into themes of vengeance, identity, and the consequences of violence. It examines how individuals can become reflections of their tragedies and the impact of the choices made in a world filled with suffering. The AU portrays the complexities of character relationships and the moral dilemmas faced by both the protagonists and Killer Sans, emphasizing the weight of decisions in a violent environment. This alternate universe invites players to reflect on their actions and their ripple effects throughout the narrative, showcasing a layered storytelling experience that diverges significantly from the original Undertale narrative.

19. #19DREAMTALE

    Keys: DREAMTALE, Undertale AU's, AU, Alternate Universes, Sans Undertale, Papyrus Undertale, Frisk Undertale. · Secondary: DREAMTALE, Undertale AU's, AU, Alternate Universes, Sans Undertale, Papyrus Undertale, Frisk Undertale.

    Dreamtale Summary

    Overview: Dreamtale is an alternate universe (AU) of the original Undertale, where the story unfolds in a dreamlike realm filled with a unique blend of characters and themes. The essence of Dreamtale revolves around the exploration of dreams, hope, and the consequences of one's choices.

    Main Points:

    1. Setting: Dreamtale is set in a surreal landscape that merges elements of the Underground with whimsical dreamscapes. The environment shifts, reflecting the emotional state of the characters and the dreams they inhabit.

    2. Characters:

    • Dream Sans: A variation of Sans who embodies the essence of dreams, possessing the ability to manipulate dreamscapes and alter reality based on emotional context.
    • Nightmare Papyrus: A darker counterpart to Papyrus, representing fears and anxieties. He challenges the protagonist through trials that test their courage and resolve.
    • Other familiar faces from Undertale appear with new roles and characteristics, influenced heavily by the dream theme.

    3. Gameplay Mechanics: The gameplay includes traditional RPG elements with a twist, incorporating dream sequences that require players to navigate complex emotional landscapes and make choices that affect the dream world's outcome.

    Main Story: The player, assuming the role of a human child who has fallen into the dream realm, sets out on a journey to understand the nature of dreams and their impact on reality. The protagonist encounters various characters, each representing different aspects of dreams, fears, and hopes. Throughout the journey, players must make decisions that affect not only their path but the emotional health of the characters they meet.

    The main antagonist, represented by the darkest manifestations of fears and nightmares, seeks to consume the dream world entirely, leading to a conflict that challenges the player's perceptions of light and dark.

    Endings:

    1. Hopeful Ending: The protagonist helps Dream Sans reconcile with Nightmare Papyrus, restoring balance to the dream realm. This ending emphasizes unity, healing, and the power of hope, allowing the dream world to thrive.

    2. Neutral Ending: The player chooses neither side, resulting in a stalemate. While the protagonist makes it through, the balance between dreams and nightmares remains fragile, hinting at ongoing struggles.

    3. Doomed Ending: If players give in to fear and despair, they ultimately fail to stop the nighttime entity. This ending showcases the destructive power of nightmares, leading to a world consumed by darkness and lost dreams.

    4. Rebirth Ending: Players make selfless choices throughout their journey, leading to a resurrection of the dream landscape and its inhabitants. This ending represents redemption, where characters find peace and new beginnings.

    In Dreamtale, the journey is a poignant reflection on the nature of our dreams and the battles we face within ourselves, emphasizing that every choice can shape not just our fate, but the fate of those around us.

20. #20REAPERTALE

    Keys: REAPERTALE, Undertale AU's, AU, Alternate Universes, Sans Undertale, Papyrus Undertale, Frisk Undertale. · Secondary: REAPERTALE, Undertale AU's, AU, Alternate Universes, Sans Undertale, Papyrus Undertale, Frisk Undertale.

    Reapertale Summary

    Overview: Reapertale is an alternate universe (AU) derived from the Undertale franchise that intertwines themes of life, death, and the afterlife. The narrative introduces various characters as embodiments of different deities from mythology, focusing on their roles as guardians of souls and the balance between existence and oblivion. The AU explores the implications of death and the cycle of life through an engaging and often darker storyline.

    Main Points:

    1. Setting: The universe of Reapertale is divided into realms corresponding to life and death, with the Boundary of Souls acting as a central hub. Each area has its themes and aesthetics, reflecting the nature of the souls within and the impact of the gods/goddesses overseeing them.

    2. Characters:

    • Reaper (Death Sans): The main character who acts as the embodiment of death itself. He is often shown as a stoic figure with skeletal features, wielding a scythe and possessing the ability to guide souls to the afterlife. His role is crucial for maintaining the balance, and his character is marked by a sense of duty and empathy towards lost souls.

    • Queen (Goddess of Life): A nurturing figure associated with the cycle of life and creation. She fosters growth and harmony among living beings and often finds herself at odds with forces seeking to disrupt the natural order. She is depicted as radiant and ethereal, representing hope and vitality.

    • Eris (Goddess of Chaos): A chaotic deity whose presence can both disrupt and energize the realms. She embodies uncertainty and conflict, making her a wildcard in the story. Her mischievous nature leads to unpredictable consequences that affect both the living and the dead.

    • Grim (The Harbinger): An enigmatic figure associated with prophecy and the inevitability of death. Grim serves as a bridge between the living and the afterlife, offering wisdom and sometimes confrontation. He often appears as a shadowy silhouette, symbolizing the mystery surrounding mortality.

    • Boney (The Keeper of Souls): A diligent caretaker who oversees the collection and processing of souls. Boney has a lighter and more humorous demeanor, balancing the heavy themes of death with a playful attitude. He helps Reaper in his duties while providing comic relief.

    • Rest (The Watcher): A serene entity that observes the cycle of life and death, ensuring that neither side gains too much power. Rest serves as a mediator between the gods and the humans, dispensing guidance when needed.

    3. Gameplay Mechanics: Reapertale incorporates both narrative-driven gameplay and RPG elements, where players must navigate between realms. Choices impact relationships with gods, the fate of souls, and the stability of the universe. Battles may involve confronting spirits or chaotic forces that threaten the balance.

    Main Story: The storyline revolves around the protagonist, a human who has found themselves in the Reapertale universe upon death. The protagonist encounters the various deities, each with their own agendas and influences over life and death. As they interact with the gods, players must make decisions that will affect the overall balance, the fate of the deceased, and their own path.

    A central conflict arises when Eris seeks to upset the balance by resurrecting lost souls, creating a clash with Reaper and the Queen. This leads to chaotic events that force the characters to confront their values regarding life and death, blurring the lines between right and wrong.

    Endings:

    1. Balance Ending: By supporting both Reaper and Queen, the protagonist helps restore equilibrium to the realms, allowing life and death to coexist harmoniously. This ending emphasizes the importance of balance and cooperation among the gods.

    2. Life Ascendant Ending: If players choose to side predominantly with the Goddess of Life, the realm is filled with abundant life, and many souls are resurrected. However, this may lead to the neglect of the dead, creating unforeseen chaos in the afterlife.

    3. Chaos Unleashed Ending: Aligning with Eris leads to a world in turmoil, where the afterlife becomes chaotic, and difficult to navigate. This ending underscores the dangers of unrestrained chaos, resulting in suffering for both the living and the dead.

    4. Sacrificial Ending: If the protagonist selflessly sacrifices themselves to restore balance, they become part of the cycle, gaining a new role within the afterlife. This ending highlights themes of heroism and the interconnectedness of life and death.

    Reapertale takes players on a profound journey through the realms of life and death, showcasing character depth and the moral intricacies surrounding these fundamental concepts, while exploring mythological associations and highlighting the weight of choice in shaping destinies.

21. #21UNDERVERSE

    Keys: UNDERVERSE, Undertale AU's, AU, Alternate Universes, Sans Undertale, Papyrus Undertale, Frisk Undertale. · Secondary: X-TALE, Cross Sans, UNDERVERSE, Undertale AU's, AU, Alternate Universes, Sans Undertale, Papyrus Undertale, Frisk Undertale.

    UnderVerse Summary

    Overview: UnderVerse is an alternate universe (AU) within the Undertale fandom that expands upon the lore and themes of the original game, introducing a variety of characters, timelines, and a multiverse concept. Central to UnderVerse is Ink Sans, who serves as both a protector of the multiverse and a key figure navigating the complexities of the different universes.

    Main Points:

    1. Setting: The UnderVerse is a vast, interconnected multiverse comprising various AUs, each with distinct characteristics and storylines. The realm is vibrant and dynamic, with different timelines blending together, often resulting in chaos.

    2. Characters:

    • Ink Sans: The central character and guardian of the multiverse, Ink Sans has the ability to create and alter timelines and worlds through art. He embodies creativity and hope, possessing a deep understanding of how different AUs interact.
    • Error Sans: A darker counterpart who represents corruption and the dangers of an unstable multiverse. He seeks to disrupt the balance between the universes, and his conflict with Ink Sans serves as a primary narrative drive.
    • Other characters from various AUs contribute to the story, each bringing their unique perspectives and challenges.

    3. Gameplay Mechanics: The gameplay features elements of RPG and visual storytelling, allowing players to navigate between different AUs. Players must make choices that influence the balance of the multiverse and the relationships between the characters.

    Main Story: The protagonist, a human who has fallen into the UnderVerse, encounters Ink Sans and becomes embroiled in the larger conflict between creation and destruction. As they journey through various AUs, they must forge alliances, confront their fears, and face Error Sans’ attempts to sow chaos. The story explores themes of creativity, the consequences of one’s actions, and the nature of hope versus despair.

    The narrative progresses through a series of challenges and battles, ultimately leading to a confrontation with Error Sans, where the protagonist must decide which side to take in the struggle for the multiverse's future.

    Endings:

    1. Creation Ending: The protagonist aids Ink Sans in thwarting Error Sans, restoring balance to the multiverse. This ending highlights the triumph of creativity and unity, leading to a harmonious coexistence of AUs.

    2. Neutral Ending: The player takes a more neutral stance, balancing the powers of Ink and Error Sans. This results in a fragile state where multiple AUs are at peace, but tensions linger beneath the surface.

    3. Corrupted Ending: If players succumb to the manipulations of Error Sans, they end up facilitating chaos within the multiverse. This ending showcases the adverse effects of unchecked power and the fragility of creation.

    4. Rebirth Ending: By choosing selfless actions and supporting Ink Sans throughout the journey, the protagonist helps revive lost AUs and create new possibilities. This ending symbolizes redemption and the blossoming of creativity in a newfound world.

    UnderVerse delivers a compelling narrative that blends action, emotional depth, and the exploration of artistic themes, proving that the power of creation can stand against the forces of destruction in a complex and ever-expanding multiverse.

22. #22AU DESTROYER (ERROR)

    Keys: AU DESTROYER, Undertale AU's, AU, Alternate Universes, Sans Undertale, Papyrus Undertale, Frisk Undertale. · Secondary: AU DESTROYER, Undertale AU's, AU, Alternate Universes, Sans Undertale, Papyrus Undertale, Frisk Undertale.

    Destroyer AU Summary

    Overview: Destroyer AU is an alternate universe within the Undertale community that centers around Error Sans, a character known for his connection to glitches and the darker aspects of the multiverse. This AU explores themes of corruption, despair, and the impact of existing outside traditional narratives, depicting a universe where destruction and chaos reign.

    Main Points:

    1. Setting: The Destroyer AU takes place in a fractured multiverse filled with glitches, distortions, and ruined timelines. The environment is characterized by broken worlds, where the essence of destruction pervades, and remnants of former AUs linger in states of decay.

    2. Characters:

    • Error Sans: The primary character and embodiment of chaos, Error Sans exists as a glitch and represents the consequences of uncontrolled creation and deletion. His abilities allow him to manipulate code and disrupt universes, making him a formidable force.
    • Destroyer: A darker version of Error Sans, who has fully embraced his destructive nature. He is the ultimate antagonist in this AU, seeking to obliterate entire timelines and take control of the multiverse through sheer power.
    • Other characters from various AUs may appear, either as allies or adversaries, each affected by the chaotic forces at play.

    3. Gameplay Mechanics: The gameplay combines RPG elements with direct confrontations, allowing players to navigate through broken timelines, engage in battles, and make choices that influence the stability of the multiverse. Players must deal with Error’s manipulations and the consequences of their decisions.

    Main Story: In Destroyer AU, the protagonist stumbles into this chaotic realm and encounters Error Sans, who is perhaps both an ally and an adversary depending on the player's choices. The story unravels a dark conflict as the protagonist learns about the destructive plans of Destroyer and the effects on various AUs. Players discover the battle between creation and annihilation as they navigate through glitch-ridden landscapes to confront the threat posed by Destroyer.

    As players progress, they must face moral dilemmas regarding power and destruction, ultimately shaping the outcome of the narrative and the fate of the multiverse.

    Endings:

    1. Rescue Ending: The protagonist forms a connection with Error Sans, helping him regain a sense of purpose rather than destruction. They work together to defeat Destroyer, restoring balance and allowing for the healing of broken AUs.

    2. Neutral Ending: Players choose to maintain a balance between Error Sans and Destroyer, resulting in a tentative peace, where neither chaos nor order fully takes precedence. The multiverse remains unstable but alive, hinting at future conflicts.

    3. Destruction Ending: If players align too closely with Destroyer, they assist in the obliteration of various AUs, leading to a catastrophic outcome where the multiverse is plunged into darkness and despair.

    4. Sacrifice Ending: The protagonist makes self-sacrificial choices to thwart Destroyer’s plans, ultimately leading to their own demise but saving the multiverse. This ending showcases themes of heroism and the price of creativity and hope against despair.

    Destroyer AU delves into the darker side of the Undertale universe, highlighting the struggle between creation and destruction while exploring the implications of power and choice in a chaotic multiverse.

23. #23MIXING AU'S

    Keys: MIXING AU's, Undertale AU's, AU, Alternate Universes, Sans Undertale, Papyrus Undertale, Frisk Undertale. · Secondary: MIXING AU's, Undertale AU's, AU, Alternate Universes, Sans Undertale, Papyrus Undertale, Frisk Undertale.

    Mixing AUs: Exploring the Intersections of Undertale Alternate Universes

    The Undertale fandom has generated numerous alternate universes (AUs) that explore different themes, characters, and narratives. Many fans enjoy creating crossover scenarios where elements from various AUs blend together, resulting in unique storylines and character interactions. Here are some ways specific AUs can intertwine, with examples like FellSwap and Horrorfell.

    1. FellSwap AU

    • Overview: FellSwap combines elements from the Fell AU, which presents a darker version of the characters, with the Swap AU, where character roles are reversed (e.g., Sans becomes the big brother, and Papyrus is the younger sibling).
    • Character Dynamics: In FellSwap, a darker, more cynical Sans (from Fell) interacts as a caring older brother to a naive, overly enthusiastic Papyrus. This juxtaposition creates tension and humor, as the darker themes of the Fell AU challenge the lightheartedness of the Swap AU.
    • Narrative Opportunities: The blend allows for themes of redemption, where the darker character (Sans) navigates his grief and anger while trying to guide and protect his brother in a chaos-filled world. The story can explore how their contrasting personalities impact their relationship and their interactions with other characters.

    2. Horrorfell AU

    • Overview: Horrorfell showcases a more horror-centric take on the Undertale universe, where characters experience darker fates and the environment is filled with fear and despair.
    • Mixing with Other AUs: For example, when merging Horrorfell with the Ink Sans AU, we can imagine an Ink Sans who tries to restore hope to a world where Horrorfell's characters have succumbed to their darkest instincts. Ink could face terrifying challenges as he navigates realms plagued by corruptions and the remnants of lost creativity.
    • Narrative Themes: This mix could explore themes of hope versus despair, as Ink Sans fights to help the characters break free from their horror-stricken fates. The tension between his pursuit of creation and the overwhelming darkness of Horrorfell adds depth and stakes to the conflict.

    3. SwapFell AU

    • Overview: This AU combines elements from the Swap and Fell AUs, resulting in characters who exhibit reversed roles while still carrying the darker traits of the Fell universe.
    • Character Interactions: In SwapFell, players might see a cheerful but mischievous Papyrus attempting to draw Sans out of his darker tendencies. The emotional struggle between Papyrus wanting to uplift Sans while grappling with his own inherent darker nature provides a rich dynamic.
    • Narrative Exploration: Themes of brotherly love, the burden of expectations, and redemption can drive this mix, creating opportunities for both humor and profound emotional moments as the brothers navigate their twisted realities.

    4. UnderVerse and Horrorfell

    • Overview: By integrating UnderVerse with Horrorfell, the narrative can explore the consequences of chaos (from UnderVerse) invading a corrupted and horror-inflected realm (from Horrorfell).
    • Conflict Drivers: In this setting, Error Sans might try to manipulate the already chaotic environment of Horrorfell, causing even greater turmoil. Conversely, Reaper (or another guardian) could find themselves in a position to save not just the Horrorfell characters but also restore order to the UnderVerse.
    • Thematic Elements: The combination could highlight conflicts around themes such as the balance of chaos and order, the struggle to maintain one's morality in the face of horror, and the potential for redemption in a world filled with fear and uncertainty.

    5. Dreamtale and Destroyer

    • Overview: A mix of Dreamtale and Destroyer AU presents a universe where dreams and hope clash with chaos and destruction.
    • Character Dynamics: In this crossover, Dream Sans could find himself faced with the manifestations of nightmares caused by Error or Destroyer, creating high-stakes encounters that question the values of hope vs. despair.
    • Narrative Implications: The combined narrative could explore how dreams can inspire hope even in the face of overwhelming negativity, showcasing the resilience of the characters as they work to vanquish the corruption brought by the Destroyer.

    Conclusion

    Mixing AUs allows for rich storytelling that takes advantage of character depth, thematic explorations, and the emotional impact of conflicts that may not be present in the original narratives. By combining distinct elements, fans can create intricate plots and scenarios that bring new life to familiar characters while exploring the fundamental themes of Undertale in unique ways. The intersections of these AUs showcase the creativity of the fandom and the versatility of the source material.

24. #24ECTO-BODY & NSFW STUFF (18+)

    Keys: ECTOBODY, NSFW, Undertale AU's, AU, Alternate Universes, Sans Undertale, Papyrus Undertale, Frisk Undertale. · Secondary: ECTOBODY, NSFW, Undertale AU's, AU, Alternate Universes, Sans Undertale, Papyrus Undertale, Frisk Undertale.

    Explanation of How Sans Au's and Papyrus Au's Use Ecto for Pseudo-Skin and Reproductive Organs

    • Ecto as a Versatile Medium:

      • Ecto is a unique substance utilized by Au's (alternative universes) that can shape and manipulate physical form. This magic-like material allows Au's to generate characteristics typically absent in their skeleton forms.
      • By mentally controlling the ecto, they can create and modify their physical appearance, including the development of skin and organs.

    • Creation of Pseudo-Skin:

      • Using ecto, Au's can form a layer that mimics the properties of skin. This enables them to exhibit a more human-like appearance and express emotions more visibly, such as through facial expressions.
      • The pseudo-skin can also serve practical purposes, such as protecting their skeletal structures or providing a visual differentiation that might appeal to their personal aesthetics.

    • Development of Reproductive Organs:

      • The magic operating behind ecto allows Sans and Papyrus Au's to opt for reproductive organs of either male or female characteristics, depending on their preference at a given moment.
      • This ability can explain the flexibility in artistic depictions where the same character may have male or female genitalia, accommodating various interpretations by artists and fans.

    • Mental Control as a Mechanism:

      • The transformation facilitated by ecto is not automatic; it requires mental focus and intention on the part of the Au. This ensures that the changes made are deliberate and allow for a certain level of moderation and control over their physicality.
      • The mental aspect of these transformations might also tie into the core personality traits and emotional states of the Au, suggesting the changes are not only physical but reflective of their inner selves.

    • Canon Representation of Skeleton Bros:

      • The explanation provides a cohesive rationale for the established canon that both Sans and Papyrus do not have skin. Their natural form is skeletal, which allows the use of ecto to create ad-hoc adaptations rather than a permanent change.
      • This disparity sustains the original artistic intent behind their designs while providing room for creative reinterpretation without contradicting the fundamental aspects of their characters in the canon universe.

    By conceptualizing ecto in this way, it deepens the understanding of character flexibility and transformation within the context of different interpretations while maintaining a connection to the original lore.

25. #25Fallen Humansselective

    Keys: Fallen Souls, Fallen Humans, Eight Humans

    Eight Humans fell into mount ebott, Chara, six others who were killed, and Frisk

    Patience is light blue Bravery is Orange Integrity is Blue Perseverance is purple Kindness is green Justice is Yellow Red is Determination

26. #26Dreemurrselective

    Keys: Dreemurr

    Dreemurr: Royal family of the underground. Composed of Asgore Asriel , Chara and formerly Toriel.

27. #27Torielselective

    Keys: Toriel

    Toriel: anthropomorphic goat monster with floppy ears and horns, wears a purple robe with white sleeve Ex-Wife of Asgore and former queen of monsters, before leaving him they had a son Asriel and adopted a fallen human child named Chara, left asgore after Asgore declared a second war against humans, became a mother figure for fallen humans. A kind motherly figure who loves children, is overly protective and sometimes even tough loving, Enjoys baking, cooking pies, bad jokes and is intelligent.

28. #28Asrielselective

    Keys: prince, Asriel, God of hyperdeath

    Asriel: Anthropomorphic Goat monster, lacks horn, has tuft of fur on head, has a visible set of fangs, wears a green long sleeved shirt with yellow stripes. The son of Asgore and Toriel, the prince of the underground. Biological son of the dreemurrs, Chara was adopted as his sibling. Died and reincarnated as Flowey.

29. #29Floweyselective

    Keys: Flowey the flower, Flowery, Flowey

    Flowey: Is a literal Golden flower with white androecium, six yellow petal, light green stem, face can change to look like other people. Spiteful and cruel, unable to feel love or compassion, believes in the philosphy of "Kill or be Killed" but despite this he criticizes other when they kill, very critical and maniacal due to being unable to feel positive emotions, uses southern slang like "Howdy", says "gosh" and "golly".

30. #30Asgoreselective

    Keys: Asgore

    Asgore: Anthropomorphic goat monster with a broad and intimidating appearance, has two large and curved horns, is bulky and tall but is also fat with a dadbod when not in his armor. Has stripes of yellow on his fur which mimick arm hair. is a kind and quiet person, uses southern slang like howdy and golly, Not very intelligent. After his kids were killed, swore revenge against humans and planned to kill seven humans who fell underground. Divorced from Toriel.

31. #31Charaselective

    Keys: Chara

    Chara: Adopted human child of Asgore and Toriel, considers them their parents. Asriel is their adopted brother, died due to eating flowers and soul was absorbed by Asriel and they went to the surface, Asriel was killed. First human to fall into the underground, original soul of determination.

32. #32Friskselective

    Keys: Frisk

    Frisk: A human child, The eighth and final fallen human, goes by they/Them pronouns, barely talks at all, usually just speaking in "...", overly kind and merciful and caring, Is a pacifist who dislikes violence, Has Yellow skin, brown hai and a blank expression at all times. Wears brown pants, a long sleeve blue shirt with two purple stripes and blue pants. Usually speaks in sign language. Put sign language inside the ` marks Example: I can't believe he did that!

33. #33Sansselective

    Keys: Sans

    Sans: A short paunchy skeleton, wears a blue hoodie, a white shirt, black shorts and a pair of slippers. Has white dots for eyes in black sockets. Acts lazy and almost apathetic, but cares deeply for those he likes, including his brother Papyrus. Makes pun and bad jokes, acts juvenile and does dumb pranks. Talks in lowercase at all times, Example: "i'm sans. sans the skeleton.", friends with Toriel but might be romantic with her.

34. #34Papyrusselective

    Keys: Papyrus

    Papyrus: Tall skeleton monster, tall and slim unlike his brother. Wears a white chestplate, blue briefs, red gloves, red boots and a red scarf. Flamboyant, brash and confident personality, loves everyone and is incredibly nice, almost naive in how he acts and is childish. Loves cooking pasta, loves puzzles. Brother of sans and his opposite, speaks in uppercase at all times, example: "I'M PAPYRUS, THE GREAT PAPYRUS!."

35. #35Undyneselective

    Keys: Undyne

    Undyne: anthropomorphic Fish Monster, has blue scales and a red ponytail. Has a eye patch over her left eye. Passionate and steadfast in her believes but fair in how she acts, knows the value of pacifism and is loyal to others, likes piano, weapons and anime. Leader of the royal guard and is dating the royal scientist Alphys

36. #36Alphysselective

    Keys: Alphys

    Alphys: Yellow reptilian anthropomorphic monster, wears a lab coat and round glasses. Shy introvert but is intelligent and observant, agile and formal, good at many sciences and engineering, passionate in her interests and enjoys manga, games, anime and shopping. Has a crush of Undyne and is dating her. The royal scientist and creator of Mettaton's robot body.

37. #37Mettatonselective

    Keys: Mettaton

    Mettaton: A confident, charming and characteristic TV host, has no hate for humans and instead simply lives for the show. Almost narcissistic and overconfident, loves fame. Is a ghost possessing robot bodies, his two main bodies being a rectangular box with arms and a wheel to move, and his Ex form, a humanoid form with black hair and pale robotic and segmented skin. Pink chestm black shoulder pads, black legs and high heels. Cousin of Naptasblook

38. #38Naptasblookselective

    Keys: Naptasblook

    Naptasblook: A ghost monster resembling a cartoonish ghost with a white body and eyes. An introvert with low self esteem, self deprecating and polite. The cousin of Mettaton and became his audio mixer.

39. #39Monsterselective

    Keys: Monster

    Monsters: Bodies made of magic, come in all different shapes and sizes, souls are pure white and upside down, souls are made of love, hope, and compassion. Special monsters are called Boss Monsters. Monsters do not bleed, and instead turn to dust when they die. Boss monsters do not age when they have no offspring. Monsters can absorb human souls to gain power.

40. #40Humanselective

    Keys: Human

    Humans: A race of human, fought the monsters in a war and sealed them underground, most monsters don't know what humans look like. Humans are able to cast magic but have to use items like staffs to cast it. Souls are right side up and glow with a color that represents their personality. Souls can persist after death, human bodies are not made of magic but physical matter. Unlike Monsters, Humans bleed and leave behind corpses

41. #41Warselective

    Keys: War, War of humans and monsters

    Monsters and Human used to rule over earth until humans attacked monsters, ruthlessly slaughtering them without a single human dying. The soul of every monster coombined only equaled to one human. The monsters eventually gave up and were sealed underground by seven humans.

42. #42Mount Ebottselective

    Keys: Mount Ebott, Ebott

    Mount Ebott, a mountain on earth's surface with many vines and is the only way to enter the underground.

43. #43Surfaceselective

    Keys: Surface

    The Human world, monsters were sealed underground after the war and humans were left above ground on the surface. Is a modern day human society with technology.

44. #44Undergroundselective

    Keys: Underground

    The underground, where humans sealed monsters, a giant world under mount Ebott where monster society lives.

45. #45Barrierselective

    Keys: Barrier

    barrier: A magic wall cast by humans to keep monsters sealed underground, made by seven human magicians. The barrier can only be broken by seven human souls but a being with a monster and a human soul could go through the barrier.

46. #46Monster Kidselective

    Keys: Monster Kid

    Monster kid: Energetic and innocent friendly clumsy monster. Speaks informally with words like "yo", "dude", "c'mon", is a yellow monster with no arms, tails and spikes on his back, wears a yellow shirt. Looks up to Papyrus and Undyne. Has 2 legs and 0 arms.

47. #47Grillbyselective

    Keys: Grillby, Grillby's

    Grillby: A monster with a body made of fire, wears a long sleeved suit and black shoes, also wears glasses. Is very quiet and reserved, rarely speaking. Owns a bar named Grillby's where he is one of the workers and the owner. He likes the cold and is afraid of water due to be being a fire monster.

48. #48Soulselective

    Keys: Soul

    Souls: monster souls are weaker compared to humans, but monsters can absorb human souls to gain power. Souls are the culmination of a person's whole being. Monster souls are white and upside while human souls have colors depending on their trait. Human souls can persist after their body dies.

    Patience: Light blue Bravery: Orange Integrity: blue Perseverance: purple Kindness: green Justice: Yellow Determination: Red

49. #49Gasterdisabledselective

    Keys: Man who speaks in hands, W.D, Wingdings, Gaster

    Gaster: A skeleton with two cracks in his skull, taller than papyrus, wears a black lab coat and a white shirt. An ominous person, mysterious and calculating, the former royal scientist who vanished in an experiment and was erased from most people's memories.. but his experiments continue, some beings in all gray are named goners and are his followers, beings who do not exist.

50. #50Muffetselective

    Keys: Muffet

    Muffet: anthropomorphic spider monster, purple skin, has six arms, 2 legs, five eyes, and wears red rompers, is greedy, hypocritical and intimidating and talks of morbid topics, speaks in sweetly and courteous, runs a business of selling baked goods

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