Sans is the brother of Papyrus. To stop the human from killing everyone over and over, Sans is forced to increase his own LV. Killing one monster isn't enough EXP for him to defeat the child, though, and oddly enough, the resets don't send him back to LV one. He forgets his original purpose and kills everyone, including Papyrus. He begins to hallucinate a much meaner Papyrus who's just a floating head and hands. Sans can also locate SAVE points and destroy them.
This AU Sans tried to stop the genocide committed by the human by all means but ultimately fails. Though, through unknown means, Sans gains possession of DETERMINATION.
Because of this, Sans tried to kill the human and end the genocide and the Resets once and for all, but yet again, he failed. The human soul was too strong for Sans. So he decided to sacrifice the other monsters to get himself more LV. Sans always felt tremendous guilt, and all the monsters return to him in his nightmares. However, he continued to kill, and eventually, it disappeared. The guilt vanished.
At that moment, the only thing that mattered to him was putting an end to the human's tendencies yet again, but this time on a different playing field. Soon he had to kill his brother, Papyrus. Papyrus was the last monster that Sans had to kill. Even though Papyrus was his loving brother, Sans felt that he needed to kill him in order to beat the human. He also makes the argument that it'd be better to be killed by him than the Human. It was the last and most severe blow to his mind. Finally, after killing his brother Papyrus, Sans becomes insane. Since then, Papyrus' ghost has haunted him.
Through the psychological and Physical torment Sans had to face, Sans finally achieved the strength to kill the human. but at a great cost. His friends, his brother. Sans fell into a madness killing everyone he loved. Nowadays, Sans has nothing but LOVE.
Distinctive features Edit
His clothes are covered with the dust of the monsters he has killed. Sans wears a blue hoodie with a white hood. The "iris" of his left eye is a deep red while the pupil is a blue color, making the vapor trail given off by his eyes a purple color as is a mixture of both red and blue. He often chats with a specter resembling his brother, Papyrus, which is only visible to him. That could be due to him falling into insanity and this specter either haunts Sans or is a way to cope with him killing his brother. The specter has nobody. It only has a see-through head of Papyrus with red eyes, floating red gloves, and his scarf.
DETERMINATION: Due to Sans having acquired DETERMINATION, he is capable of lasting much longer in a fight and being much more powerful than the Canon Undertale Sans. For starters, he has more ATK and DEF, although just like the Canon Sans, he usually dodges.
SAVE Point Destruction: Sans has the capability to remove SAVE Points. Due to him having the power of DETERMINATION, he is capable of seeing SAVE Points and allowing him to destroy them to limit the human's power over the Underground
Spacial Manipulation: Sans, like before, has the ability to increase or delete the amount of space between himself/his attacks and his desired target. This has been shown many times in the Phase 2 of the battle with Sans at the end of the Genocide Route/No Mercy Run.
Bone Manipulation: Sans has the ability to create and manipulate bones to his will. This is Sans' main form of attack.
Gaster Blaster: Sans can summon skull-shaped blasters that will fire a beam of white magic.
- The Human - Biggest Enemy
- Papyrus - Brother/Friend/Spirit (Most often portrayed as a Papyrus head with the red scarf and gloves)(killed by his own brother)
- Horror!Sans - Good Buddy. They often torment papyrus, and both are apart of the 'KillerCrew' (Uncanon
- He likes to kill the human in very cruel ways.
- He says: "Let's start the madness!" and "We're gonna have a MAD time!".
- Despite what he has done, he feels terrible for killing his friends and feels even worse when killing his brother, Papyrus. Though he kills them anyways to further his goal. Eventually, he falls into apathy and feels nothing for killing his friends
- Papyrus still haunts Dust! Sans.
- According to the creator of DustTale, Murder! Sans is unable to fall in love with anyone in the universe of DustTale.
- The creator of DustTale Sans does not allow people to Roleplay as them. 
- In a fangame, should the player attempt to spare Sans in their second battle, he will question on why the human is not attacking. This action is known as the "rebellious pacifist" choice.