Undertale AU Wiki

Welcome to the Undertale AU Wiki, the main place for documenting Undertale's AUs. If you wish to contribute, just know that it is REQUIRED for you to read the Rules and Guidelines and the Policy of the Wiki BEFORE doing so.

As this is an AU Wiki, this wiki is NOT meant for characters. The Undertale OC Wiki exists for those. This Wiki is also not meant for AUs that do not have presence anywhere else, and those should be put on the Undertale AU Ideas Wiki.

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Undertale AU Wiki
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* But nobody came.

* This article contains information that is from a cancelled AU, an AU that has been put on an "Indefinite Hiatus", or an AU that has not had a story update in a year. As such, some information here may not be found in any established story, and could be considered non-canon.

Time of Last Story Update: June 26, 2023

Time of Cancellation: January 10, 2024

YellowTale, not to be confused with Undertale Yellow, is a crossover between Undertale and Pokemon where Frisk is replaced by Yellow from the Pokémon Adventures Manga. The story focuses on Yellow as she travels through the Underground, and later her life on the Surface with the Monsters. The story takes place approximately three years after the events of the Emerald Chapter in Pokemon Adventures. Within those three years, Yellow has traveled to the regions of Unova, Hoenn, Sinnoh, Kalos, and Alola. The story begins not long after Yellow returned home from Alola.

Characters[]

Undertale Characters[]

Sans[]

Sans is basically unchanged from Undertale. He currently resides in Pallet Town with Papyrus, Gaster, and Kirlia.

Papyrus[]

Sans's younger brother (as we all know) has no changes to him whatsoever.

Gaster[]

After having reoccurring dreams of the so called "Man Who Speaks in Hands", Yellow asks Sans to take her to Waterfall. It is revealed that Yellow actually encountered Gaster's followers, and even the former Royal Scientist himself. After entering the mysterious door, Yellow formally meets Gaster, who then tries to take her soul to exit the Void, but is stopped by Sans, who helps his father escape. He then moves to the Surface and is usually seen in his lab, which used to belong to Sans.

Undyne[]

Upon moving to the Surface, Yellow tried to to find places for the monsters that would suit them, and for Undyne, a place like Waterfall, which would be Cerulean City. Not long after she got settled, she became friends with the Tomboyish Mermaid, and Gym Leader of Cerulean, Misty. Undyne still has a relationship with Alphys.

Alphys[]

When Yellow wanted to find a place like Hotland for Alphys, she turned to Cinnabar island, where she introduced Alphys to the scientist and Gym Leader, Blaine, and the two bonded over their love of science. Like mentioned above, Alphys is still in a relationship with Undyne. She also works as a teacher at the Trainer's School in Viridian City.

Mettaton and Napstablook[]

The two cousins are ghosts, so where would Yellow send them to? Why, Lavender Town of course! Thanks to the Ghost Pokemon, Napstablook has become a little more social, but is still a bit of an introvert. He also continues to make music and raise snails. While Mettaton lives with his cousin, he is often seen at his new MTT Resort located on an island near the Seafoam Islands.

Toriel[]

Goat Mom has decided to forgive Asgore for his deeds, and now lives with him, Yellow, Chara, and Asriel in Yellow's old house. Like Alphys, she's a teacher at the Trainer's school.

Asgore[]

After being forgiven by Toriel, Asgore became a gardener, and is responsible for most of the flowers around Viridian. He once mentioned wanting to open a Flower shop, but doesn't know where it would be.

Asriel[]

After being defeated by Yellow at the Barrier, Asriel was left to turn back into Flowey, until the Human Souls combined themselves into one, so Asriel could be himself. Upon learning about the threat that is Chara, Asriel was forced to reveal his past as Flowey to everyone. He later gave half of the Human Souls to Chara, so she could live, but was later given them back in exchange for the Justice soul he had, which was Yellow's cousin.

Chara[]

When Yellow reached the end of her original route, she met Chara, who asked for her soul in exchange for everyone's lives back. When Yellow refused, Chara proceeded to kill her, but was stopped by Yellow's Pikachu, Chuchu. Chara then told Yellow that she could reset without giving up her soul, but that was only to get her to stop crying. Some time after the Barrier was destroyed, Chara came back and started killing Pokemon (whether or not she killed any humans or monsters is unknown). Since Chara knew how much the Viridian Forest meant to Yellow, she mostly killed Pokemon there, until she was stopped by Asriel, who reminded her that they were still best friends. After being forgiven, she was given three of the Human Souls by Asriel in order to live. Over time, her original soul started to reform. When Asriel had to give up the Justice Soul, Chara gave the souls back, since she didn't need four.

Temmie[]

The Temmies are scattered throughout the region, but the Tem Shop Temmie resides in Celadon City, where they run their own Tem Shop in the Department Store. They also attend cooleg at Celadon University.

Added Characters[]

Yellow[]

Yellow Caballero (later Caballero-Dreemurr) is a Pokémon Trainer, Coordinator, and Performer from Viridian City in the Kanto Region. After losing her parents at a young age, she was raised by her Uncle, aunt, and older cousin, but her aunt eventually left after an incident that involved Yellow's cousin going missing. Yellow later goes on to become a Dexholder. After losing a Pokémon battle against new fellow Dexholder Emerald at the Battle Frontier, she decides to travel to the Unova region to become a stronger trainer, and eventually winning the Pokémon League there. She also traveled through Hoenn and Sinnoh, where she became a Pokémon Coordinator, Kalos where she became a Pokémon Performer, and Alola. Not long after she returned home from Alola, Yellow’s Uncle passed away. Devastated over the loss of her Uncle, Yellow ran away, although she wasn’t paying attention to where she was going, and wound up falling into the Underground. After freeing the monsters, Yellow joined the Dreemurr family of Toriel, Asgore, Asriel, and later Chara, as well as reuniting with her own cousin who disappeared years ago. Yellow originally did Genocide after being tricked by Flowey, but that was mainly plot for Chara. Upon resetting, Yellow blocked the genocide route out of her head, but was forced to remember it after Chara started terrorizing other people, monsters, and Pokemon.

Kirlia[]

The first Pokemon to fall into the Underground, and only one to live there. While most her past is unknown, as a Ralts, she accidentally fell into the Underground. After stumbling through the Ruins and Snowdin, she collapsed in front of a house due to hunger, exhaustion, and being cold. Thankfully, the house she collapsed in front of belonged to our favorite skeletons, who took her inside after a young Papyrus discovered her. After persuading Gaster to let Ralts stay, young Sans and Papyrus went to Asgore, who let them keep the Pokemon. Sans and Papyrus would often turn to Chara after learning something new about Ralts, since Chara came from the Surface and knew a lot about Pokemon. Some time after Gaster fell into the Void, Ralts evolved into Kirlia while trying to save Papyrus. She later learned the Hidden Ability Telepathy so she could communicate with others. She mentioned she once touched a Dawn Stone, but nothing happened, confirming her gender, or the stone was a fake. She enjoys Sans's puns and sees both him and Papyrus as her brothers.

Clover (name not final)[]

Clover is Yellow's cousin, who disappeared when Yellow was young. It was eventually revealed that he fell into the Underground. While his journey is unknown, he eventually got severely wounded by Mettaton, and later killed by Asgore, and had his soul placed in New Home with the other souls by the latter. When Asgore showed the Human Souls to Yellow, Clover almost immediately recognized his cousin, and after Yellow's fight with Asriel, it was Clover's idea to combine himself with the other souls so Asriel could have a soul of his own. Eventually, Clover decided to reveal himself to Yellow. One night, Yellow noticed the Justice Soul in Asriel glowing. After learning it was her long lost cousin, Yellow persuaded Asriel to give her the soul, which she gave to Gaster to revive. Clover now lives with his unnamed mother in Saffron City.

Ash[]

The hero of the Pokemon Anime, Ash Ketchum met Yellow before he went to the Orange Islands. Two years later, Yellow told Ash about the Unova Region, where he decided to travel to. He later invited Yellow to study at the Pokemon School in Alola. He has the soul of Bravery.

Red[]

The first Dexholder Yellow ever met, Red is one of Yellow's best friends. Although he won the Indigo Legue in the past, it is unknown if he still holds the title of Pokemon Champion. He is one of Alola's Battle Legends along with Blue, who runs the Battle Tree with him. Red has the soul of Perseverance.

Blue[]

The leader of the Viridian City Gym, Blue is one of the grandchildren of Professor Oak. Like Red, he is the other Battle Legend in Alola, and also runs the Battle Tree. As his name would suggest, Blue has the soul of Integrity.

Green[]

The oldest Pokedex holder, Green is known as the "Pesky Woman" by Blue. While she claims to also be a Battle Legend, Red and Blue deny it, saying that the only reason she was allowed to help run the Battle Tree, was because she "threatened to kill the two boys". As her name implies, Green has the soul of Kindness, which Blue thinks is impossible for her.

Locations[]

Added Locations[]

Pallet Town[]

The starting place for all new Pokemon Trainers, as well as the homes of Red, Blue, Green, Ash, Sans, Papyrus, Gaster, and Kirlia. There's also Professor Oak's Lab, filled with Pokemon from all over the world.

Viridian City[]

The location of the Trainer's School, and the home of Yellow, Asriel, Chara, Toriel, and Asgore. Blue runs the gym there.

Viridian Forest[]

Yellow’s favorite place to hang out. It's also the main place of Chara's massacre prior to her redemption. Every ten years, a child, like Yellow, is born with mysterious powers relating to the forest. Mt. Ebott can be found deep in the forest.

Pewter City[]

Nothing important there, except for it being the home of Ash's friend Brock. There's also a gym there, of course.

Cerulean City[]

Undyne's home, as well as Misty's. The Cerulean Gym is also present there.

Vermilion City[]

Nothing worth mentioning, although it is implied that the River Person lives there. And there's also the gym there, and the Pokemon Fan Club.

Fuchsia City[]

Some of the dogs live there. It has a gym, and the Safari Zone.

Saffron City[]

Not important, but Monster Kid and Clover live there. There's also the gym, Fighting Dojo, and Silph Co.

Lavender Town[]

The home of Mettaton and Napstablook (and also Mad Dummy). It also has the infamous Pokemon Tower.

Celadon City[]

Home of Tem Shop Temmie. Muffet also has a bakery there. Jerry is also usually found at the Celadon Hotel, only because of the free WiFi, which sucks in his opinion. He never buys a room, and everyone hates him, because he's Jerry. Can't forget the gym, the department store, or the game corner.

Cinnabar Island[]

Alphys's home. It also of course has a gym. It also has the old Pokemon Mansion.

MTT Resort[]

Not much to say, except Burger Pants works there. Located on an island near the Seafoam Islands. It's mostly the same as the original, except it also has a water park and an arcade, like many major hotels do.

Story[]

Trivia[]

  • Yellow never actually traveled through the regions mentioned above, her story is expanded into a prequel that I'll hopefully start making in the future.
  • Clover's name is not final. It is a beta name, taken from the protagonist of Undertale Yellow.
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