Quarterspin (previously known as Quarterswap or Sidetale) is an AU where characters swap in groups of four. It was created by Star the Triple Devil on October 18, 2016. It was put on a hiatus for over a year before the creator decided to bring it up again on December 19, 2018. As such, it is in early development, and all currently existing material is from late 2016 or early 2017.
About the AU
In Quarterspin, everything is changed by a quarter. Characters are swapped in groups of four, location themes are shifted, and various other changes.
Long ago, monsters and humans ruled the lands in peace. However, war broke out between the Boss Monsters and the rest of monsters and humans. After years of war with no clear result, the Boss Monsters and the rest made a deal to split the lands, and have humans and monsters inhabit one side and Boss Monsters inhabit the other side. The most powerful mages of both sides separated the lands with a magical fence known as Fence E-Wolf.
After years, it became apparent that the Boss Monsters managed to get the better land. There was also a weak part in the Fence, which could be crossed by a Boss Monster.
The Sideland was ruled by King Napstablook, accompanied by his cousin Happstablook. The two used to live in the Icy Ruins. The two found a human child with the rare determination SOUL and no home, and decided to adopt the child and name them Chara. However, as Chara started freezing in their old home, the three moved to the other side of the kingdom. Some years later, in X015, a boss monster kid (named by the player) found their way to the Sideland, and due to a lack of other family, they were taken in by the King as well.
One day, when making Glamburgers (Happstablook's secret recipe), the Monster Kid accidentally put darkness in the burger. After eating it, Napstablook became surprisingly aggressive, which was unusual, as most of the time Napstablook was fairly boring. When infected by the darkness, Napstablook mortally wounded Monster Kid. As a last wish, Monster Kid wished to see the village where they came from again, and Chara agreed to take them there. Chara absorbed Monster Kid's SOUL and the two went past the barrier. The Boss Monster who saw Chara thought they had killed Monster Kid and attacked. Chara fought back and killed the monsters who attacked. Chara then proceeded to approach a nearby village with murderous intent, and it was only the part of Monster Kid still inside them that managed to make them stop. What Chara didn't notice was that one of the Boss Monsters from the earlier attack managed to survive, and attacked Chara. With their last strength, Chara returned to the other side of the fence, where they collapsed in the darkness. Their SOUL shattered and the pieces of it fell into the darkness. Napstablook, influenced by the darkness, declared war on the boss monsters. Happstablook disagreed with the decision and returned to the Icy Ruins. He also changed his name to Metta since he didn't want to be associated with Napstablook anymore.
Years later, the Royal Scientist Sans attempted to bring Chara back in an experiment. This, however, failed, and instead created Gaster, a being of pure darkness. During this process, he also ended up creating the amalgamates.
Asgore and Toriel, two boss monsters, decided to cross Fence E-Wolf and settle down on the other side of the fence. It was there where they met and befriended Metta, and started to live in the MTT Mansion. After some time, the two wanted to build homes of their own, and they decided to do so in Lavafall. The two enjoyed their life there and befriended a local, Grillby. However, after Grillby's brother died, their life started going downhill. Toriel returned to the Icy Ruins with the couple's newborn son, Asriel, while Asgore moved forward. He met the Royal Scientist, Sans, who agreed to give Asgore a disguise so the locals wouldn't recognize him as a boss monster. Asgore became known as Dreemurrbot and everyone believed he was a robot built by Sans.
Toriel raised Asriel on her own, occasionally helped by Metta, in the Icy Ruins, and never told him who his father was. Toriel occasionally visited the outside of the Icy Ruins to see how things were going but did not tell Asriel about it.
During the Game
Asriel wanders off at the most distant part of the ruins, where he meets Gaster. Gaster pretends to be a friendly skeleton, but turns out to be evil and attacks Asriel. Asriel is saved by Metta. Metta then figures out Asriel is old enough to want to explore places on his own, so he decides to train him.
- Asriel: Asriel appears in the role of Frisk, and is the main character in Quarterspin. His decisions are largely based on the player's.
- Gaster: Gaster appears in the role of Flowey. He speaks in Wingdings but his speech is translated to readable English. He appears as the final boss in a Neutral Route. In a Pacifist Route, it is revealed that his true identity is Chara.
- Metta: Metta appears in the role of Toriel. He is a pink ghost living in the Icy Ruins. His home is known as the MTT Mansion. In the Pacifist Route, it is revealed that he is the cousin of Napstablook and that his true name is Happstablook.
- Toriel: Toriel appears in the role of Napstablook. She is the worried mother of Asriel who believes he shouldn't be wandering off the Icy Ruins alone. Asriel proves he is capable of going off on his own after defeating his mother and Metta in a fight.
- Undyne: Undyne appears in the role of Sans. She lives with her girlfriend Alphys and the two have a shared interest in anime. She does not attack Asriel, which is later revealed to be due to her past friendship with Asgore. Unlike Sans, who is only fought in Genocide, Undyne is fought in all Routes except Pacifist, but in a Neutral Route, the encounter can be escaped.
- Alphys: Alphys appears in the role of Papyrus. She desires to become the puzzle designer for Papyrus, Head of the Royal Guard, but is too nervous to use the puzzles in their full strength. She also hesitates to fight Asriel, and after she is spared, she takes Asriel home to roleplay anime.
- Frisk: Frisk appears in the role of Monster Kid. They are a human with the determination trait, and they quickly befriend Asriel. They also think Papyrus is very cool. In a Genocide Route, Frisk can be killed, which causes their SOUL to shatter and half of the pieces land on Asriel and the other half land on Papyrus.
- Papyrus: Papyrus appears in the role of Undyne. He is the Head of the Royal Guard (his dream job), and while he is very powerful, he is also kind, and as such, is not very good at capturing boss monsters. He thinks there is good in Asriel, even if he is killed in a Neutral Route, but in a Genocide Route, he uses his full strength against him. In a Pacifist Route, Asriel can hang out with Papyrus and attempt to cook spaghetti, but it causes his house to burn (which explains why Alphys prefers instant noodles over taking cooking lessons from Papyrus).
- Sans: Sans appears in the role of Alphys. He is the brother of Papyrus and the Royal Scientist. The failure of his past experiments have made him very pessimistic, and he covers it by making puns. He is aware of different timelines, but this is only revealed in a Pacifist Route.
- Dreemurrbot: Asgore appears in the role of Mettaton. He is introduced as a robot, but in his final encounter (Pacifist/Neutral Route), it is revealed that he is Asriel's father. He reveals this is the reason why he never truly attacked Asriel.
- Napstablook: Napstablook appears in the role of Asgore. He is the king of the Sideland. He does not really care about anything and just lets himself be filled with darkness before the fight to make things easier. After the effect of the darkness wears off, he lets Asriel defeat him. If he is spared, he tells him that he really misses his cousin.
- Chara: Chara appears in the role of Asriel. In a Pacifist Route, they are the final boss. After spared, Chara breaks the barrier.
- Monster Kid: Appears in the role of Chara. This character is named by the player and has no true name. They show up in the end of the Genocide Route, where they say how not cool all of Asriel's acitions were.
- Canine Unit: The canine unit if the Royal Guard switch places, but keep their original encounter strategies. Nothing much changes about them other than their placements.
- Lesser Dog: Lesser Dog appears in the place of Doggo.
- Dogamy and Dogaressa: Dogamy and Dogaressa appear in the place of Lesser Dog. Their encounter is the only optional one.
- Greater Dog: Greater Dog appears in the place of Dogamy and Dogaressa.
- Doggo: Doggo appears in the place of Greater Dog.
- Aaron: Aaron appears in the role of Grillby. He owns a gym near Alphys and Undyne's home, and Undyne trains there daily. In a route where Alphys survives, Undyne takes Asriel there. The members of the Canine Unit also train there.
- Grillby: Grillby appears in the role of Shyren. He can be spared by tasting his food and saying it is good.
- Annoying Flower: Flowey appears in the role of the Annoying Dog. This flower appears in various locations. Its most notable appearance is when it absorbs the legendary artifact, and leaves Friendliness Pellets behind.
- Toby: Toby appears in the role of Temmie. Tobies are a type of white dogs living in Toby Village. They are all experts in hacking video games, except one, who writes books instead.
- RG 02 and RG 03: These two appear in the roles of RG 01 and RG 02. 02 is a male dragon and 03 is a female crocodile. The two feel like they do not belong with each other at all, as 02 would rather be eating ice cream and 03 would rather collect garbage. They can be spared if Asriel gives them good advice. They can also be encountered so that one is killed and the other is spared.
- Shyren: Shyeen appears in the place of Muffet. Shyren is a singer who is too shy to appear in publicity. Shyren has agents who sell her albums (which do not show her face) in various locations. Shyren can be easily spared if she sees that Asriel has bought one of Shyren's albums.
- Gerson: Gerson appears in the place of Nice Cream Guy. He is an old tortoise who goes to various locations to sell ancient items.
- Nice Cream Guy: Nice Cream Guy appears in the place of Snowdin Shopkeeper Bunny. He sells ice cream, but his sales aren't going well as it is always spring and not summer.
- Noodlepants: Burgerpants appears in the place of Gerson. He is a nervous shopkeeper who feels like he has wasted his whole life selling stuff in Lavafall. He got his name because one time when he tried to impress a girl (RG 03) who went past to visit the trash by preparing noodles, he ended up getting them in his pants.
- Toby: One of the Tobies runs a shop. He sells Dog Residue. Asriel can sell his items to them, and Toby gets especially excited over Friendliness Pellets. If enough money is paid to Toby, he can be sent to develop a video game. After he returns, a cheat code can be bought from him. This cheat code is an armor that makes fights easier.
- Catty and Bunny: Catty and Bunny (RG 01) appear in the roles of Bratty and Catty. The two do not feel connected in the way Catty and Bratty are. While Catty appears to enjoy trash, Bunny prefers ice cream, and recommends buying from Nice Cream Guy instead of the two. Both of them also had good friends who went to join the Royal Guard instead of becoming shopkeepers.
- Dreemurr Resort Shopkeeper: The Shopkeeper Bunny appears in the role of Burgerpants. She sells various types of tea that Asgore likes.
- Muffet: Muffet is an enemy in Lavafall. She can be spared by paying money or performing a spider dance.
- Temmie: Temmie appears in the role of Gaster. She was the Royal Scientist before Sans. She speaks in broken English. She has followers who also speak in broken English.
- hooman: This character appears in the role of Goner Kid. This is a Frisk lookalike who appears in Lavafall.
- The intro is slightly longer than in Undertale, with the extra explanation of boss monsters.
- Battle mechanics are altered due to the playable character being a monster.
- The Delta Rune is replaced with the Kappa Rune. This, however, in not an anagram.
- Undyne is encountered in a Neutral Route as well, and the battle works similarly to her fight in Undertale, except that she cannot be killed, only escaped from. This fight does not happen if Asriel has never killed any encounters.
- Once Upon a Bad Time
- Start Menu
- Your Darkest Friend
- Oh! Time To Train
- Icy Ruins
- His Theme For Hot And Cold
- Unnecessary Tension
- Enemy Approaching
- Goat Fight
- Game Over - Spooky
- Mansion (Extra Glamorous)
- Heart Crusher
- Oh No!
- His Theme For Flowers And Fun
- Greater Bass
- Mysterious Place
- Mel Town
- Anime Roleplay!
- Anime Tension!
- Anime Fight!
- Danger Mystery
- Quiet Lava
- Bird That Carries You Over A Disproportionately Small Gap
- Comfortable House
- Better Pie
- Holiday Pie
- Feeling Like Home
- Toby Village
- Toby's Shop
- Bones of Kindness
- It's Dreemurr Time!
- Metallic Mountains
- Another Medium
- His Theme For Leaves and Rain
- Stronger Monsters
- Can You Really Call This A Home, I Don't Live Here Or Anything
- Dreemurr's Report
- Dreemurr's Report - Extreme Edition
- Siren's Singing
- Wrong Enemy !?
- Determination of the One Child
- Determination to Escape the Dungeon
- It's Sunny Somewhere Else
- COLLEGE Approach
- Last Chance!
- Turn Around...
- Fighting For Fame
- For Some Determination
- Long Elevator
- Song That Actually Plays When You Fight Undyne
- The Choice
- Not Surprised
- FIGHT ME 1V1
- DARK NAPSTABLOOK
- The One Who Speaks In Hands
- Your Darkest Nightmare
- An Ending
- He's Playing Trombone
- Here We Are
- Oh! We Meet Again
- Don't Give Up
- Resets and Changes
- Bleed in Despair!
- SAVE the World
- Their Final Form
- Final Power
- Menu (Full)
- Bring It In, Guys!
- Last Goodbye
- But the Stars Refused to Give Up
- Battle Against True Greatness
- Power of "FLUFFY"
- THE HERO THEY ALL NEEDED
- Good Night
- Once Upon a Time is sometimes replaced with Megalovania, but sometimes, it remains.
- Your Best Friend is replaced with Gaster's Theme.
- Toriel is replaced with Oh!
- Ruins is replaced with Papyrus.
- Uwa!! is replaced with His Theme.
- Dogsong is replaced with Your Best Friend. Enemy Approaching keeps its melody but uses note intervals similar to those in Your Best Friend. Originally Temmie related songs remain the same but now have a dog sound.
- The new version of Dogsong does not use the dog soundfont, but instead different one.
- Ghost Fight is replaced with Heartache.
- Determination is replaced with Spooktune.
- The intros of the Hotel and Home leitmotifs are switched. Both keep the Once Upon a Time leitmotif.
- Heartache is replaced with It's Showtime! and Metal Crusher.
- Sans is replaced with Undyne and parts of Ruins. Parts exclusive to It's Raining Somewhere Else are changed as well.
- Papyrus is replaced with Alphys.
- Alphys is replaced with Sans.
- Undyne is replaced with the intro of Papyrus.
- Spooktune is replaced with Toriel.
- It's Showtime! and Metal Crusher are replaced with Asgore.
- Oh! is replaced with Determination.
- Asgore is replaced with Ghost Fight.
- Asriel is replaced with Megalovania (a different part from the one used in Once Upon a Time).
- Parts of Battle Against a True Hero are replaced with Uwa!!.
- Megalovania is replaced with Battle Against a True Hero.
- Originally, the Canine Unit was supposed to be known as the Plant Unit instead of having its members swapped. In the original version, Doggo was replaced with a cactus, Dogamy and Dogaressa were a pair of Echo Flowers, and Greater Dog and Lesser Dog were Flowey like flowers. Lesser Flower could grow taller by having Asriel water it.
- In the original version, Monster Kid died by injecting too much darkness instead of getting attacked by Dark Napstablook.
- As of now, it is not fully certain how the Dummies, Riverperson, secret characters (besides Gaster related ones) and minor characters switch.
- Echo Flowers are not certain either.