In 19 BBY, a space battle took place in the Atoan system in the Ghost Nebula between forces of the Galactic Empire led by Darth Vader, and Atoan defenders.
During his search for missing Garoche Tarkin in the Ghost Nebula, Darth Vader interrogated the captured Lady Saro, an Atoan sorceror, as to the whereabouts of the admiral. Saro responded that, provided her demands were met, she would lead the Imperial forces to the wreckage of the Star Destroyer formerly commanded by Tarkin.
Encouraged by this, Vader launched from his own Destroyer in his black interceptor along with an escort squadron of V-wings and underlings Voca and Shale to search the wreckage for clues.
However, the Imperial fighters could only discover signs of sabotage to the Destroyer before coming under attack from Atoan starfighters. Despite several early kills by the Atoans, Vader soon organized his squadron, and the Imperial pilots held their own, coming to understand that speed and agility were key factors - factors that the Atoan ships did not represent.
Following the turnabout, Vader ordered his wingmates to break away, and harried the remaining lone Atoan ship, forcing it to crash-land in a hangar on the ruined Destroyer. Vader killed one of the pilots, leaving the other alive for interrogation.
The pilot revealed critical information before Vader executed him; a tar-covered world was to be the next target in the search for Garoche Tarkin; Vader decided upon a stealth attack, knowing also that his orders from Emperor Palpatine were to kill Tarkin so as to engender anger and determination in Garoche's father.