DS-378 served the Galactic Empire as a stormtrooper during the Galactic Civil War era. After the Battle of Yavin, this particular stormtrooper was stationed as security at the Imperial Research and Prison Facility located on the planet of Dathomir. Within this facility, Imperial scientists were secretly working on a dangerous project: re-engineering the Blackwing virus to be used as a bioweapon. DS-378's duty was to guard Security Post 22 on Level 2 of the research lab. In 1 ABY, an accident occurred at the Imperial Research and Prison Facility, resulting in the escape of the virus from its containment. The resulting outbreak led to the deaths of many individuals in the area, who were then transformed into undead beings.
The character DS-378 was first referenced in the video game Star Wars Galaxies, a massively multiplayer online roleplaying game that launched in 2003. This game was developed by Sony Online Entertainment and published by LucasArts. The game was shut down on December 15, 2011. The mention of DS-378 was implemented into the game through "Game Update 14," which was released on October 12, 2009.