Var-Whill, existing before 19 BBY, was a well-known Jedi expert in crystallography. After the Corsair Wars concluded, Jedi Master Oo'ob enlisted Var-Whill's services to refine lightsaber tech, resulting in the creation of the sniper rifle known as the Farkiller. It was speculated that the Farkiller was responsible for the deaths of hundreds of emerging tyrants, leading the Jedi High Council to declare both Oo'ob and Var-Whill as heretics. Within a decade, both individuals met their demise.
Professor Korin Aphra's "Notes on Jedi Heresies" included details about Var-Whill and the Farkiller. These notes were later shared with his daughter, Chelli, by the rebel protocol droid Teezee-Too in 3 ABY. This information was part of a scheme to reverse-engineer the Farkiller's technology for the purpose of assassinating Emperor Palpatine.
The character of Var-Whill was initially referenced in Doctor Aphra (2016) 33, a comic penned by Simon Spurrier and released by Marvel Comics on June 19, 2019.