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*Have you thought about a world where everything is exactly the same...
*Except you don't exist?

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HackedTale is an AU created by Scarlet-Streak on Archive of Our Own and Wattpad. It centers around the concept of Sans and Flowey realizing they're in a video game and attempting to rewrite the code to improve their situation. Currently, the story for the AU is divided into a prologue and three books but is still in progress. However, the guide for the AU is published on both of the aforementioned sites. The information will eventually be transferred to this page, making this a WIP.


Note: All the original characters from the game are in this AU. However, they will be experiencing multiple different changes in design explained in this section. The author apologizes for the formatting issues.


Main Characters

  • Sans is one of 3 characters in the story with an added determination trait, and is the only one of this trio to not have a voided soul. His soul's base traits are Integrity (Blue) and Justice (Yellow). However, taking into account his low HP (Which is doubled as Hope) and the fact that his backstory in this AU contains a lot of damage to him soul-wise and emotion-wise, the colors are incredibly dull. The soul itself is covered in cracks that are filled in with Determination (Red).
  • Papyrus's soul seems white at first glance. However, it has a rainbow sheen, portraying the fact that Papyrus's soul contains trace amounts every trait. This decision was made by the author, who couldn't settle on two dominant traits for him. It is much brighter and healthier than Sans's.
  • Flowey has a voided soul, which is portrayed as empty darkness in the traditional shape of a soul to show an absence of light symbolizing the missing soul traits. It's surrounded by tendrils of Determination which is the only thing holding his code together.

Supporting Characters

  • Toriel's soul is a base of Kindness (Green) with a core Dedication (Pink).
  • Asgore's soul is a base of Integrity (Blue), fading to Perseverance (Purple), and finally Dedication (Pink). Mettaton's soul is mostly Dedication (Pink) with swirls of Sincerity (Royal Blue) and Audacity (Burnt Orange). Alphys's soul is a base of Kindness (Green) with a core of Justice (Yellow) and Courage (Orange).
  • Undyne's soul is a base of Justice (Yellow), fading to Courage (Orange), and finally a hint of Determination (Red).

Other NPCs

  • Monster Kid has a solid green soul for kindness.
  • Grillby’s soul is mainly light blue for patience, with splashes of lime green for courtesy and indigo for rectitude.
  • Muffet’s soul is pink, with touches of purple and red.
  • Nicecream guy has a base of green, with swirls of red, purple, and royal blue.
  • Burgerpants has a more complicated soul. His soul is dull, for a lack of hope, but that doesn’t change his assigned traits. The soul will start blue, then fade to purple, then to red as it goes in towards the center.
  • Lesser and Greater Dog have solid color souls, with Greater dog’s being orange and Lesser dog’s being goldenrod.
  • Dogamy and Dogaressa are orange, red, and pink.
    • Dogamy’s is orange on the outside, then red, then pink in the middle.
    • Dogaressa’s is the opposite, with pink on the outside, then red, then orange in the middle.
  • Doggo's base color is purple, with splashes of light blue and red.

Clothing Alterations

Book 1

No outfit changes

Book 2

Most base outfits stay the same, with the only major exception being Papyrus. Sans and Flowey have blood on them from being in the closest and longest proximity to injured Frisk. Flowey’s are mostly on his petals, while Sans’s have more stories behind them. He will accumulate them over time, with the most noticeable of these is the palm print on his cheek from the end of Book Two. Other stains will be on his jacket or shirt from where her wounds have bled while he carried her.

Most of the character’s hands, and, in Flowey’s case, leaves, have dried blood on them from taking turns


Concept art for Flowey in Book 2 drawn by Scarlet Streak

stopping the worst of Frisk’s bleeding or carrying her through the game. It's especially apparent on Papyrus, Sans, Toriel because of the fact that their hands are white.

Papyrus wears more functional travel clothes after being told by Sans his Battle Suit wouldn’t hold up during the journey in an attempt to get him not to come along. This consists of an old sweater from Toriel (May or may not have belonged to Asgore) and a pair of pants sewn together from scraps. His normal gloves and boots will be replaced by yellow knit mittens from Toriel (Belonging to Asgore as well) and a pair of old red rain boots he found.

Frisk acquires multiple wounds over the course of this book, the most noticeable being her legs, which were shattered in the fall.

Characters only affected by Frisk’s bloodstains/other minor alterations like soul color:

  • Toriel
  • Undyne
  • Alphys
  • Mettaton (EX)
  • Asgore
  • Monster Kid
  • Muffet
  • Grillby

Characters with no alterations:

  • Mettaton (Normal)
  • NPCs like Nicecream Guy, Bratty and Catty, Burgerpants, etc.
  • NPCs like Froggits, Whimsums, etc.

Book 3

Warning: Spoilers ahead

Gaster, appearing for the first time in book 3, but his altered design will appear under a separate category.

Sans wears long black pants instead of basketball shorts, running shoes instead of slippers, and a blue jacket with grey stripes down the side of the arms instead of his sweater. He also wears a pair of black gloves, the kind with the fingers meant to interact with touchscreens. Flowey has a tiny yellow and green sweater for when he travels in the Void, knitted for him by Toriel. The warmer clothes are because of how cold the void is. It’s difficult to last in there for long without proper clothing 

In Chara’s appearance, they will be in their mid-teens, in the green and yellow single stripe sweater, but covered in dust and their own blood.

Doctor Gaster

Gaster's role and appearance in the AU is incredibly difficult to sum up, so he will not be included on this page. However, information about him is available on other sites.


Note: This section is currently under construction considering that the wording is incredibly informal, taken directly from the creator's notes.

  • The Void - The Void in this AU is the source code for the game. Basically, it’s all the technical stuff hidden in the layer behind the output (AKA the game itself). There are defined ways into it, like the Core or the Gray door, but only certain characters whose souls either contain determination naturally or have been injected with determination can survive the experience of being decompiled while in the void. However, ways can be forcibly made into it, like Sans’s short cuts which do not cause decompiling. This is because the aforementioned main doorways act as a compiler, processing the code of the game to become the output that is the game itself, while these other ways are literally to allow access to the code with the intent of looking at or changing it.
    • The image in my head is kind of like space, but instead of stars, planets, etc. the code is floating around. Code varies in colors, and active code will be lit up. The base color for the writing is blue, while variable types and the like (print, if, for, etc) would have colors based on type. For example, variable type declarers might be yellow or something. Again, it will be very cold, because machines need to be kept cold to function.
  • The Core - The Core took a lot of thinking to find a tie-in, but, as I was coming up with Gaster’s backstory, it hit me. The Core is the Compiler, or the thing that translates the source code into binary that the computer can run, effectively the life support of the game. If the core stopped working, the code for the game would also stop working. So, one more time, here’s how a Compiler works (Because it’s really important):
    1. Starts as Coding language (Understandable by Humans)
    2.  Becomes Binary         
    3.  Enters Compiler
    4. Becomes something that can create an Output, either standing alone or going through an interpreter
  • Frisk vs Chara - Ok, I didn’t really explain this well in book one, so let me elaborate. At the beginning of Diving into the Code, Sans states that they’ll be able to see what kind of day it’s going to be. That’s because Frisk’s (Or Chara’s) appearance depends on which route they are doing. In this story, Frisk is a young child of around 6 years old, and Chara is a teenager of around 15 years old. If the player does a true pacifist, the avatar takes on the appearance of Frisk. If they do a true genocide, the avatar takes on the appearance of Chara.
    • You might be asking what happens when the player does a Neutral route. Basically, if neither the true pacifist nor true genocide requirements are met or are possible, the avatar takes on aspects of both characters for the duration of the neutral route. A constant appearance is Frisk’s sweater and Chara’s open eyes. The age of this hybrid appearance is reliant on how many monsters they’ve killed, each age based on one of the nine main neutral endings. The hybrid looks around 7 years old if everyone has been spared, and around 14 if a no mercy neutral route has been completed.
  • Realities, Barriers, and Time flow - So, as I was writing all this stuff, I realized something. I needed to figure out how there was an actual world on the other side of the Barrier for the monsters to come into. No world was coded in the game beyond a few images and the sunrise scene, but one will be necessary for the beginning of Book 3. Also, a world will be needed on the other side of the screen, for a player to exist, and the underground will have to basically exist simultaneously with these two separate worlds, henceforth referred to as realities. These realities are extremely similar, following the same flow of time. The biggest difference is the barrier between them and the underground. Our reality, which we’ll call Reality 1, is divided from the underground by the screen. We view it as a game. There is no way to travel between the two places. The barrier between the other reality, Reality 2, is actual Barrier, as it exists in the game. That barrier can be broken, allowing the monsters to pass into Reality 2. The monsters and Frisk can pass between the underground and Reality 2 whenever they want, but the people of Reality 2 cannot enter the underground, because they aren’t connected to the code. Mount Ebott exists in Reality 2, but not in Reality 1. The city outside of Mount Ebott doesn’t have a name, so the readers are welcome to name it whatever they want. Another important fact is that the underground’s time flow doesn’t parallel Realities 1 and 2. It has its own flow, based on the events that happen in the game, using the save files and main timeline as references. It’s kind of like a bubble, with the barrier creating the bubble itself.
  • Souls - In this AU, each character's base code takes the form of their soul, making the soul an incredibly important part of the game. A monster’s soul will reflect whether they have had their memories restored or not. A white soul will represent a monster who has not had their memory restored, while a soul with restored memory will start to show the dominant color traits. Children’s souls will be solid colors. The reasoning is that white is a reflection of all the colors back to the eye, which means that the monster souls have all the colors present at once. This is because they don’t exist long enough to form a dominant soul trait. With each reset, they are at most a day or so old, returning their souls to an almost newborn state. Returning the memories (or days of life) to a monster allows their soul to settle upon a trait or multiple traits. Excluded from this idea is Frisk, whose soul has a predetermined color.
  • Putting a Soul Back Together - The idea of fixing the corrupted code of a voided soul is a very important part of this story. There are three characters with unstabilized corrupted souls: Flowey, Gaster, and, by the end of book two, Frisk.
    • As stated earlier, souls/code can become corrupted by being injected with a trait that doesn’t belong to it. If the trait is determination, the corrupted code with continue to hold itself together, and can stabilize by combining with another piece of corrupted code, which is why the amalgamates aren’t corrupted, but Gaster is. Flowey’s code stabilized by combining with one of the flowers, but that isn’t really important to the story. Souls/code can also be corrupted by someone meddling with them, which is what happens to Frisk.
    • Once a soul with a trait has been corrupted, said trait will drain out of it as the corruption spreads. The difference between this type of corruption and the other type is that the code will not hold itself together, which is why Frisk’s soul will immediately need to be placed in a holding unit until a non-corrupted version of the code can be put into it. This leads us to how a corrupted soul can be fixed.
      • The only method of fixing a corrupted soul is, as stated above, to replace the corrupted code. Also, if the soul had a trait, the trait must be returned to it to complete the process and, if the soul didn’t have a trait, the trait must be removed. But, if the code hasn’t been repaired and the trait holding the soul together is removed, the soul will fall down.



The Prologue is not very important to the story, besides setting up the idea of the AU. It can completely be skipped.

Book 1: Diving Into the Code

Book 1 consists of Sans and Flowey discovering the code and making their initial edits, all leading up to the events in Books 2 and 3.

Book 2: The Dying Pacifist Ending

This book has yet to be completed. A description will be added after completion.

Book 3: The Source Void

This book has yet to be completed. A description will be added after completion.


This book has yet to be completed. A description will be added after completion.