Hyperdust

Hyperdust is an OC made by TheOnlyDust. He is Dust!sans, only he has murdered everyone in timeline #667 (finally killing Frisk/Chara), and is continuing through the multiverse and timelines to rid of all Charas and Frisks. He killed everyone in the Undertale of his timeline, which should have killed him but he came to another timeline (after murdering everyone he could kill in other AU's) to escape dying. He is no longer insane, and now fully evil.

Personality
He is a sadistic, cold-blooded killer, that won't ever stop. He is emotionless, cold, and sarcastic.

Abilities
He is at LV 999, and is 1EXP from LVL 1000, also known as the Murder LVL.

He is a massacre-er, a term coined by UnderfreshFan to describe a "destroyer", but one who isn't interested in destroying au's (UnderfreshFan puts (former) Cross!Sans, Hyperdust, Zacksamsis (Ask Undertale) and Renegade Sans in this category).

Dust Sweep
A character from an au (other than Core!Frisk and Coeus) that he has destroyed appears, and does his bidding (like Ink!Sans summoning Sans ability in the Ink Sans Battle).

Rainbow Bones And Blasters
Normal Sans attacks, except they're the colours of the rainbow, and they do 999DPS instead of 1DPS.

Dust Weapons
He can summon any au characters weapons (except Core!Frisk and Coeus).

Trivia

 * He hates Core!Frisk and Coeus because they can alter their timelines.