Dust is the first of the gang to make a pact with Nightmare. He is a Haunted Sorcerer (from Grim Hollow: Player's Guide) and a Great Old One Warlock. (He was probably a different kind of sorcerer before the events described below but his magic was permanently changed after he killed his brother.)

Very limited emotional range, almost never expresses the few emotions he does have. Doesn't speak unless absolutely necessary and when he does he uses as few words as it takes to get the point across. Will not talk about his past, ever. Refuses to be a victim, won't take anything lying down.

Dusts story starts in an unremarkable city-state in which he grew up with his brother, Paps(not short for papyrus, just Paps). When Dust and Paps are young adults a new leader takes over with a very strong human supremacy rhetoric. Non-humans (monsters) immediately begin facing discrimination and violence against them. The less human and/or the more "scary" a monster looked the worse off they were. So a Dwarf might experience discrimination while a tiefling would face active violence. It wasn't long before monsters started getting rounded up, deported (if they were lucky), enslaved, or killed. When a rebellion rose up Dust and Paps didn't hesitate to join. The fight was long and bloody, until a particular massacre ended with Dust as the sole survivor on either side of the fight (Paps wasn't in that fight he dies later). Both parties blamed Dust for their losses and he was ostracized. Paps tried to help him but Dust ran before Paps could follow him. Dust ends up finding an old tome that explains how to summon the god of suffering, saying that he will grant you the ability to ease your own suffering and/or the suffering of someone you care about in exchange for you causing more suffering that you would have faced had he left you alone. Dust summons Nightmare and makes a pact; Nightmare will enhance Dust's magic and Dust will gladly give a slow and painful death to everyone who caused this mess(aka everyone in the corrupt government or who supported it, and everyone in the resistance who blamed him and threw him out (everyone in the resistance except for Paps)). Dust goes on a killing spree, killing as many as he can before the rest flee. In the midst of said killing spree, however, he is confronted by Paps. Paps tries to stop Dust, to convince him to run away together. Dust tries to just incapacitate Paps but ends up killing him anyway. From that moment on Dust hallucinates Paps' ghost who just tells Dust what a horrible person he is for everything he did and parrots anything negative Dust may think about himself.

P.S. please ignore my poor excuse for a Gaster Blaaster, it was my first attempt at ever drawing one and it really wasn't my focus. It will get a redesign eventually. Also ignore the level ratio on the drawing, that is not set in stone.

DND AU Masterpost

post for DND AU Killer Sans

Dust Sans originally by @ask-dusttale

Below the cut are some screenshots I took from DND Beyond while creating Dust and a PDF of the resulting character sheet.