Dubbed "the Duchess" in a cruel reference to Duchess Satine Kryze, the Arc Pulse Generator represented a superweapon conceived by Sabine Wren. This occurred while she was a student at the Imperial Academy situated on Mandalore. Designed to target the beskar alloy prominent in Mandalorian [armor](/article/mandalorian_armor], the weapon functioned by intensely overheating the metal, leading to the disintegration of the wearer. However, it possessed the capacity to be recalibrated against other materials, such as plastoid, a key component of stormtrooper armor. Upon grasping the Empire's intentions for the weapon, Wren deserted the Galactic Empire and made an attempt to obliterate the prototype. Despite her efforts, the Empire, along with its regents on Mandalore, managed to salvage and reconstruct it. This devastating weapon was then deployed during the civil war on Mandalore throughout the Imperial Era, until Wren and Bo-Katan Kryze ultimately brought about its destruction.
Some years prior to the early rebellion directed against the Galactic Empire, Sabine Wren held the position of a cadet at the Imperial Academy located on Mandalore. As the highest-ranking student in her class, Wren was known for her competitive nature and her willingness to tackle challenges that other students deemed too difficult. One such challenge was the creation of a [superweapon](/article/superweapon], which ultimately resulted in the Arc Pulse Generator. This weapon was maliciously named "the Duchess," a reference to the late Duchess Satine Kryze, a pacifist who governed Mandalore during the Clone Wars. Wren engineered the weapon to specifically target the beskar alloy found in Mandalorian [armor](/article/mandalorian_armor], with the intent of disintegrating the soldier wearing it.
After Wren learned that the Empire had tested the weapon on her own people and intended to continue its use, she sabotaged the device, destroyed its schematics, and abandoned the Empire. She later aligned herself with rebels who would eventually become part of the Alliance to Restore the Republic. Wren was under the impression that she had successfully destroyed the weapon, but the Empire managed to retrieve and rebuild it. Although rumors circulated regarding the Empire's experimentation with such a device, no other Mandalorian clans could confirm the Duchess's existence. By 6 BBY, the Empire had already deployed the Arc Pulse Generator at least once, specifically to exterminate the Dizonites, the sentient inhabitants of Dizon Fray who were resisting the construction of a refueling station on their planet.
Following Clan Wren's rebellion against Clan Saxon, the ruling clan of Mandalore that was allied with the Empire, a civil war erupted on Mandalore. Governor Tiber Saxon made preparations to deploy the weapon against the insurgents, installing it on an AT-DP Arc Cannon Prototype. Despite its diminished power compared to Wren's original design, Saxon ordered its use against Clan Wren during the conflict, resulting in the deaths of several clan members. Grand Admiral Thrawn expressed disappointment that the weapon did not meet its full potential and suggested that Governor Saxon capture Wren to enhance and refine it.
After witnessing the weapon's destructive power firsthand, the rebels devised a plan to destroy it, with Wren volunteering to lead the mission, feeling personally responsible for its creation. Wren, accompanied by a strike team, boarded Saxon's Star Destroyer with the intention of destroying the weapon and erasing all related data from the Imperial databanks. As Ezra Bridger, Fenn Rau, and the other members of the team engaged Imperial forces in the hangar, Wren and Bo-Katan Kryze located the weapon. However, they were captured by Saxon, who threatened to kill Bo-Katan unless Wren repaired the weapon. Thinking quickly, Wren deceived him into believing that she had amplified the weapon's power. Instead, she recalibrated it to target stormtrooper armor rather than the beskar in Mandalorian armor. When Saxon activated the weapon, it incapacitated his own Imperial troops. Wren then utilized the Darksaber to breach the weapon's core, causing it to explode and destroy the Star Destroyer as Wren and her strike team made their escape.