Undertale AU Wiki

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WiseTale is one of the many prequels to Undertale, it is branched to the main timeline however whether it's the original history of Undertale is still unknown to this day.

The AU revolves around the 7th forgotten human that fell after Chara, his name is Krotos. Krotos is looking for his siblings as they fell down to the Underground but after meeting Toriel in the Ruins he found out that his family is killed by the King named Asgore. Krotos, horrified by the revelation, demanded to get past Toriel but she stood in his way as they both reluctantly fought. Eventually Toriel let Krotos go as he travels to Snowdin.

Krotos fights against many monsters and severely wounding them in the process. The scientists Gaster, Sans and Alphys try to stop the human from reaching Asgore but all attempts failed so instead they tried to save many lives as they could. The wounded were in critical condition as Alphys and Sans try to help them but there was nothing they could do. Sans got desperate and uses extracts of Determination and injects them to the monsters which surprisingly worked to everyone's relief. However a day after, the wounded began melting and Sans accidently created the Amalgamations as both he and Alphys were horrified.

Krotos eventually made to Asgore's throne room and they both discuss why they were there. Krotos shows a picture to Asgore as he horrified that the children he killed was Krotos's family but he explains his past as well and how he lost Chara and Asriel to the humans. After there was nothing left to discuss they went to the barrier as Krotos sees his family's souls in containers which angered him. Asgore said his farewell to him and they both fight in a bloody battle. Both were bruised and beaten but Krotos stood out on top but before he could kill Asgore, Gaster teleports him back to the lab.

Before Gaster teleported he injected himself with large amounts of Determination and told Sans and Alphys a plan to trap the human in the Determination Extractor room and they agreed to the plan. As Gaster teleported Krotos to the Determination Extractor room he overloads the Determination Extractor as Sans teleports inside to save him but Gaster stops him before he could. Gaster in his final moments said Entry 17 to Sans while Krotos is infuriated that Gaster denied his revenge on Asgore. The Determination Extractor fires two beams at Gaster and Krotos. Gaster shatters through time and space by his creation, then a part of him is infused with Sans. Krotos on the other hand is erased from time and space as the world envelopes in a bright light as both cease to exist.


Undertale Characters


Gaster is the Royal scientist of the Underground along with his two co-workers Sans and Alphys. Gaster always smiles as he wears a grey scientist lab coat along with a white shirt, he also has black formal trousers and shoes to go along with his outfit. Gaster's personality is serious and demanding but he is also kind and caring and not afraid to crack a joke to lighten the mood. Gaster wants to help the King and monster kind as best as he possibly can but can be a bit stubborn doing tasks that are above his capabilities.


Sans is a scientist that helps Gaster with his work giving him new ideas and different solutions. Sans wears a white lab coat, a dark navy blue t-shirt, he also wears black formal trousers and shoes. Sans's personality is much more serious and is very easily agitated when something does not go his way. Sans hardly ever makes jokes and is more focused in finishing his tasks. Sans follows Gaster's orders even when entirely disagrees with him but can often leads to arguments later on. Sans at times is lazy and enjoys the company of others but in stressful situations Sans can get depressed and will loathe himself if he cannot save others from their demise.


Alphys is another scientist that works for Gaster. Alphys wears a light blue lab coat and her personality is that she is confident, organised and resourceful. Alphys prepares herself in all kind of situations normally taking care of the lab. Alphys helps Gaster experimenting on the human souls and discovering the power of Determination before Sans took over for her.


Toriel the caretaker of the Ruins guides Krotos through the Ruins and offers him to stay at her house. Toriel wears a dark violet royal robes embedded with a large golden crest in the middle along with long white sleeves. Toriel knew of Krotos's family and tried to stop them from going forth in the Underground but failed to do so as well with Krotos.


Asgore the King of the Underground murdered Krotos's family one by one. Asgore took and prisoned their souls in containers waiting for the next human to come. What he doesn't know is who that will be.

Added Characters


Main article: Krotos

Krotos is a young feminine adult who journeys through the Underground to finds his siblings that fell before him. Krotos's is a male with a slim physique, his general appearance is that he has hazel eyes and long light brown hair that extends all the way down to his back. Krotos wears a long dark coat with many pockets and straps added on as they outlined in grey. Krotos also wears dark walking trousers along with grey fleece and boots. Krotos appearance is quite undistinguishable from another person or monster's perspective as they can't determine whether he is male or female. Krotos at times has to clarify his gender although it doesn't bother him it can get awkward at times.

Krotos carries a large backpack around him that contains survival kit as well as a bow and arrow to protect himself. Krotos's personality is quite calm and relaxing even witty sometimes but when challenged he is quite adaptable, cunning and perseverant. Krotos has an elder mentality as he acts more wise and mature than his age shows but once he losses something dear his personality becomes bitter and cold, even using profanity once he his enraged.


Violet dresses in a purple blazer wearing a black tie as well as wearing formal black trousers and shoes. Violet's appearance is that she has deep dark brown eyes and long straight dark brown hair. Violet is the soul of Perseverance as she always strive for her dreams.


Sapphire wears a dark navy blue tutu and black ballet shoes, as she normally practices ballet along side with her brother. Sapphire is the soul of integrity believing herself that she is whole for who she is.


Amber wears orange and grey women's sports gear, she normally spars with her brother. Amber is the soul of bravery not afraid of challenging others and herself.


Aqua not bothered by appearances, wears grey shorts, a light blue jumper and a black t-shirt. Aqua is quite lazy and carefree, she is also quite patient with others and does not get angered easily. Aqua is the soul of Patience as she is calm and collected.


Emerald is caring, energetic and kind young child believing everyone can be a better person if they were just kind. Emerald likes cooking as she normally wears an green apron with black t-shirt, trousers and pink slippers. Emerald usually helps Krotos to take care of the family, cooking for all of the family. Emerald is the soul of Kindness as she helps others the best she can.


Garnet has a strong sense of justice believing that those who harm others should not go unpunished. Garnet will stand up for others who cannot protect themselves as he trains with Amber to learn self-defence. Garnet wears a bright yellow cowboy hat, a yellow jacket and trousers along with yellow boots. Garnet is the soul of Justice as he wants to protect as many people as he could.


Dom is the father of Krotos as his main mentor throughout his life. Dom teaches Krotos boxing and martial arts so he can protect himself. Dom and Krotos hike together while carrying large rucksacks on their journey. One night Dom argues with his wife whether Krotos's siblings should stay or not. Dom wanted to give the siblings away due to the lack of money but his wife disagreed which resulted him stabbing his wife killing her in the process. Krotos confronted Dom telling his father he is a Deadman but Dom tries to reason with Krotos but he was having none of it. Dom is then attacked by his own son and is killed by him as he watches his father die.


Jacqueline is the mother of Krotos as she take care of him and his siblings. Emerald helps Jacqueline take care of the house as they both do the cooking, washing, and cleaning together. Jacqueline deeply cares for everyone and does everything she can to keep them together which why she is so enraged how her husband could give them away. Jacqueline denies and resents the thought of it but it resulted in her death.


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