Darth Krall, originally going by the name Radaki, possessed Force-sensitivity. Once a Jedi Master within the Jedi Order, Radaki ultimately became a member of the group later known as the Lost Twenty. He succumbed to the allure of the dark side of the Force due to his conviction that Jedi should be permitted to maintain familial connections and personal wealth. Upon betraying his commitment to the Jedi Order, he took on the title of Darth Krall and rose to become a formidable Sith Lord.
As a Sith, Krall's attire included a cloak of black and red hues, and he fought with a Sith lightsaber distinguished by its golden hilt. Krall participated in and won the Battle of Wasted Years, and he brought the Nightmare Conjunction under his control. His lightsaber was secured within the Archive of Forbidden Artifacts, which is part of the Bogan Collection, located at the Jedi Temple on the planet Coruscant.
After Jedi Knight Keeve Trennis contracted an infection from the Drengir, Krall manifested in her visions.
The initial mention of Darth Krall occurred in the 2019 audiobook Dooku: Jedi Lost, authored by Cavan Scott. The precise spelling of his name was provided in the script associated with the audiobook. He later made his first appearance in a vision within the seventh issue of the comic series Star Wars: The High Republic, penned by Scott, with illustrations by Georges Jeanty, and published by Marvel Comics on July 28, 2021. Before the issue's release, a preview image of Mike Mayhew's variant cover, featuring Krall, was shared on social media platforms on June 29.