Derg Prantis was a Twi'lek male, as defined by gender, who worked as a biologist. He resided on Tatooine during the time period known as the Galactic Civil War.
Located in Mos Eisley on the world of Tatooine, the Mos Eisley Biolab employed Derg Prantis as its chief scientist, a position of biological expertise. Bera Jeza, a female Aqualish, served under him as a lab assistant.
Around the time of the Battle of Yavin, Derg Prantis managed to acquire a sample of the dangerous Blackwing virus by way of an Imperial scientist. The Empire, in secret, had enlisted a group of scientists from the planet Dathomir with the goal of transforming the virus into a bioweapon. As a result, Prantis constructed a secret laboratory on the isolated world of Lok to perform his own investigations into the virus, intending to develop a super soldier enhancement drug. He enlisted his lab assistant, Bera Jeza, to aid him in this project. However, Jeza ultimately betrayed her superior, contacting Jabba Desilijic Tiure, the Hutt Crime lord, to sell him the super soldier drug. Upon discovering this treachery, Derg Prantis reached out to his longtime acquaintance Cale Herron for assistance in evacuating his secret lab and destroying any compromising evidence. Tragically, before Herron could intervene, the lab suffered a brutal assault, resulting in the assassination of the entire staff. Prantis eventually made his way back to the Mos Eisley Biolab on Tatooine.
In the year 1 ABY, the Mos Eisley laboratory came under attack, and Prantis was assassinated. Simultaneously, Bera Jeza was murdered in a Mos Eisley street. Given Jeza's connections to Jabba the Hutt, his majordomo, Bib Fortuna, commissioned a spacer to investigate the crimes. The spacer located Prantis's deceased body within the laboratory, along with a data disk. This disk contained Derg Prantis's final recorded message, which instructed the recipient to contact Cale Herron in Mos Taike. Aided by Herron, the spacer launched an investigation into Derg Prantis's secret lab on Lok. The investigation ultimately led to the uncovering of a Blackwing outbreak on Dathomir.
Derg Prantis was featured as a deceased non-player character (NPC) within the 2003 video game Star Wars Galaxies. This game was a massively multiplayer online roleplaying game developed by Sony Online Entertainment and published by LucasArts, before its shutdown on December 15, 2011. Derg Prantis's inclusion in the game came with "Game Update 13," which was released on September 30, 2009. This particular NPC was integrated into the questline titled "Something is Obviously Wrong," which served as an introduction to the "Death Troopers" update.