Asusto, a minor world covered in forests, was situated in the Outer Rim Territories' Tamsis Nebula. This planet was saturated with the power of the dark side of the Force and frequently served as a destination for smugglers. The final surviving member of the Presagers hailing from Hakotei concealed themselves upon this world. By deceiving Jedi Master Lene Kostana and her Padawan, Sifo-Dyas, the Presagers lured them into an ambush on Asusto under the pretense of pursuing a supposed path to Sith artifacts originating from Karazak.
The audiobook Dooku: Jedi Lost, penned by Cavan Scott and released in 2019, marked the initial appearance of Asusto. The script for the audiobook provided the specific spelling of the name Asusto.