Iannos Tyrek was a Human male scientist who worked for the reconstituted Sith Empire. However, during the Cold War, he switched his allegiance and joined the Galactic Republic.
Tyrek was stationed on Balmorra, where he began to dislike his job with the Empire due to the limited creative opportunities it offered. Consequently, he made the decision to defect to the Galactic Republic, hoping to focus on creating medical technologies rather than weapons. Eventually, a young Sith being trained by Darth Zash discovered him, murdered his Balmorran Resistance protectors, captured him, and brought him back to the Imperial Base on Sobrik. While there, he created a serum that granted the apprentice immunity to toxic waste, a necessary component for retrieving an artifact belonging to Tulak Hord from a contaminated vault. After the apprentice received the serum, they executed Tyrek for his act of treason.
Iannos Tyrek is a character that the player interacts with in the Sith Inquisitor storyline within the MMORPG Star Wars: The Old Republic.
If the player is playing as a light-side Inquisitor, they have the option to convince Tyrek to go to Sobrik by assuring him that he will be allowed to return to the Republic once he has developed the Colicoid serum for them. When the player arrives to collect the serum, they can choose to honor their promise and permit him to return to the Republic, authorizing a shuttle to transport Tyrek to a location where he can safely reach Republic forces. During this exchange, Tyrek grows increasingly perplexed by the Inquisitor's actions, and suggests that they accompany him to the Republic, but the Inquisitor can only refuse.