Undead Trooper

Undead Troopers were stormtroopers of the Galactic Empire who had been infected by the viral agent known as the Sickness and between the Battle of Yavin and the Battle of Hoth an outbreak of the virus occurred. After dying a painful death, those troopers had been turned into mindless, walking corpses with cannibalistic urges. Studies revealed that, because of the infection, Undead Troopers were slower than living humans, but had an improved ability to sustain damage.

The virus allowed the Undead Troopers to communicate telepathically and learn. Acting as one, the Undead Troopers were willing to organize themselves into a deadly swarm and launch coordinated strikes on Imperial and Rebel Alliance forces alike. They even managed to reprogram and hack turret controls and security measures at fallen sectors to their advantage. This gave them the ability to fortify overrun bases against possible counter strikes, using blaster cannons, walls, and shield generators to fight off hostile contacts. Imperial scout troopers and Heavy Weapons Stormtroopers that succumbed to the illness were classified as Scout Undead Troopers and Heavy Undead Troopers, respectively. Their level of skill and coordination earned them the nickname "Army of the Dead".

Undead Troopers first appeared in the Star Wars Legends novel, Death Troopers, as undead stormtroopers infested by a Sith plague dating back to the days of the Old Republic. They were later canonized in the mobile game Star Wars: Commander, as "Death Troopers," through a limited-time campaign released in 2014. The Death Troopers were renamed to "Undead Troopers" in a 2016 limited-time event for Star Wars: Commander, most likely to avoid confusion with the newly introduced elite stormtrooper variant. This confusion was used in-universe as well, with Emperor Palpatine capitalizing on fearful rumors of the undead "Death Troopers" to name the elite black armored variant.