BinaryTale (also called Underbinary or Bin-Tale) is an AU created by ADgee. This AU centers primarily on Chara and W.D Gaster, but have other characters as well.

During the year of 201X, a young girl named Chara was with her friends, playing in her house. Everything was fine.

That is until someday they heard of the legends of Mt. Ebott. They decided to investigate and check if those were true. It was their worst mistake. After checking curiously, Chara fell through the hole.

This caused a mysterious entity to create a copy of the original "Undertale". But it failed. A strange file labeled "=)" corrupted the copy.

Chara found herself in an empty void, with the corrupted AU (shown as a piece of paper.). She wasn't alone though, a scientist skeleton named W.D Gaster was with her.

Soon, the corruption grew to the point it started shattering the copy apart. 

The pieces separated and vanished. That is, except one which both managed to save. After this tragedy, they both started to rebuild the entire universe from a single fragment.



The human who fell throught Mt. Ebott into the void. In this AU, Chara's female. She doesn't change very much design-wise. She is currently working with W.D Gaster in order to rebuild the universe.


A skeleton with slight cracks on his skull. He wears a black labcoat. He has lines of 0s and 1s printed on the bottom of the coat. He became a friend of Chara since they both started working together.


A "mirror" born from a part of Chara's SOUL as a "core piece" to keep the AU fragment stable. They have the colors of the Blue Screen (Windows). They as well share some of Chara's memories.


Slightly corrupted from recreation, has blurry memories of Asriel. He still doesn't try to kill Frisk, as well, helps them.

Changed/New Concepts

Commands (Buttons)

  • REBOOT: Restarts the AU without affecting the values.
  • COPY-PASTE: Lets the player select a piece of code and make a replica of it (used sometimes for cloning/reviving deceased people.).

Codes and Values

This shows some values and strings in the AU's source code and how they work and affect the AU.

Numerical Values

Here are some of them.

maxHP- Determines the player's max health. Can be changed through various ways.

curHP- Determines the player's current health. Can be easily changed through many ways. Minimum is 0.

noR- Indicates the amount of resets the player has made. Resets to 0 when performing a True Reset.

An example of an use is during the Genocide Route:

if.char:["Sans"]-curHP:[0]~then.maxHP:[(current maxHP)+(99-current maxHP)]

This will change the player's maximum HP to 99 (and LV to 20).

Non-numerical Values



The AU's story can be seen in Wattpad.


  • Binary!Gaster
  • Binary!Flowey
  • Binary Chara