By the time of the Galactic Civil War, Sorin served in the armed forces of the Galactic Empire, obtaining the military rank of general. During the months leading up to the Battle of Hoth, Sorin oversaw the development of a new type of improved Scout-class 2-M repulsor tank, the . Sorin maintained a base on the planet Cholganna where he tested a new deflector shield system for his tanks. The tests showed promise with the shield system which proved effective against conventional weapons, but it continued to draw too much power. Sorin hoped once that hurdle was overcome, the technology could be adapted to other vehicles and starfighters. He also performed weapons tests at a compound on the planet Aleen, which were a complete success and gave Sorin confidence that they would be able to begin production soon. He logged his progress on his shuttle's computer.
After the Battle of Hoth, Sorin was dispatched to the planet to eradicate the remaining rebel forces left behind after the evacuation. He stationed himself in Echo Base and sent patrols out into the barren Hoth landscape to search for rebels, and utilized his new Mark III Repulsor Tank as a way of field testing it. Desperate to prove himself to the Empire, Sorin put a bounty on rebel survivors to aid in his extermination. This bounty brought the attention of the bounty hunter Dengar, who sought to collect Sorin's bounty.
Several days after the Battle of Hoth, while Sorin was berating one of his captains in the hangar where he kept his shuttle, a group of rebels infiltrated the hangar via a tunnel. Sorin commanded the captain to take his men and search the tunnels, and as they marched for the tunnels they spotted in rebel squad. As the squad fended off the snowtrooper captain and his men, the engines of Sorin's shuttle began to flare. Unbeknownst to Sorin, while he was admonishing the captain, two of the rebels, Lieutenant Talcon and Corporal Kish snuck aboard his shuttle and were in the process stealing his ship. As the fight continued, Dengar and Wampas joining the fray, and Sorin sustained a wound on his shoulder. Wounded, Sorin retreated behind a locked door, as the remaining rebels board his ship and flee from the planet.
The rebels discovered Sorin's data logs, but did not find an Imperial transceiver aboard until it was too late. General Sorin used the Imperial transceiver on his shuttle to locate its whereabouts, which he learned the group of rebels had taken refuge in a small village named Haven on the planet Ison. General Sorin ordered all personnel to report to his , which floated above Echo Base, in preparation for his invasion of Ison. The group of rebels heard Sorin's broadcast, so they set off to stop him before he could leave for Haven. While Sorin was aboard his flagship, the rebel squad returned to Hoth and operated the still functioning V-150 Planet Defender ion cannon in an attempt to destroy Sorin's Star Destroyer before it left for Haven. They managed to hit the ship, but the shot only temporarily disabled the shields. The squad utilized the brief window to board the Star Destroyer, flying into an exposed launch bay and crashing along the hangar floor. The rebels were too late however, and Sorin's Star Destroyer entered hyperspace on a course to Ison.
Sorin arrived above Ison and began his invasion. He deployed his first and second division and admired the view of his coming victory. As an alarm starts to blare, Sorin discovered that the rebels made it to the bridge of his flagship. He ordered for the bridge to be locked down, but the rebels overpowered his forces, forcing him to flee the bridge. The rebels then send his starship crashing onto the planet's surface. As the rebels fought Sorin's forces that besieged the village, Sorin made his way back up to the bridge of the crashed Star Destroyer to take command of his men. Despite his command, Sorin's forces are no match for the rebel squad. They defeated his forces and made their way to the bridge where they confronted Sorin for the last time, killing him, and putting an end to his ambition.
Sorin was a vicious leader who had no regard about the survival of his own soldiers, let alone civilians. He valued recognition from Galactic Emperor Palpatine, which he hoped to gain after the success of his improved repulsor tanks.
Sorin was created for the Return to Hoth expansion set and the General Sorin Villain Pack, supplementary material for the Star Wars Legends strategy board game Star Wars: Imperial Assault, which was released in 2015. Sorin was introduced into canon via the "Return to Hoth" campaign added to Legends of the Alliance, a companion app for Star Wars: Imperial Assault, in 2019.
This article assumes a specific path is taken in the campaign, which can very depending on the choices of the players.
- Star Wars: The Rise and Fall of the Galactic Empire