The Battle of the Cowl Crucible unfolded as a bizarre conflict between the Galactic Empire and a band of miners near the Cowl Crucible. While the Galactic Empire's naval forces, commanded by Darth Vader, ventured into the crucible's heart to secure cortosis, the area's Rebels initiated an assault on the Imperial fleet. The crucible served as a conduit between the galaxy and potentially another universe or unknown realms. Vader experienced an odd premonition of a blue sword and attempted to grasp it. Following this vision, he instructed his captain, Wermis, to maintain the fleet's position. Through the Force, Vader telepathically contacted his apprentice, Galen Marek, who was also present. Marek, too, was experiencing a vision, this one of a woman holding the very blue sword Vader had envisioned. He used Force lightning to eliminate her and seize the sword. Simultaneously, in the real world, Marek lost consciousness, and his vessel, the Rogue Shadow, suffered a crash landing on an uncharted world. Upon regaining consciousness, Marek aimlessly traveled northward. Vader pursued him to this planet, encountering Captain Juno Eclipse.
Yoda on Dagobah detected this peculiar disruption between the two realities, experiencing visions of a warrior battling both stormtroopers and Tusken Raiders. This warrior then launched an attack on Vader, and Yoda, physically manifesting in this unfamiliar world, found himself under assault by a monstrous creature.