Mashallon was a Jedi Knight of the Jedi Order, a female Human. She served as an investigator during the time of the Cold War that existed between the Galactic Republic and the resurgent Sith Empire.
Mashallon was dispatched to the planet of Balmorra in 3643 BBY, acting on the instructions of Jedi Master Nomen Karr. Her mission was to investigate an Imperial spy who had infiltrated the Republic forces stationed there. She managed to record a conversation. This conversation was between Commander Rylon, an undercover Imperial spy, and the apprentice of Darth Baras. The recording confirmed Rylon's treachery and indicated a threat to expose Baras' entire spy network. Unfortunately, the Imperials detected her presence, preventing her from reaching her ship. Consequently, she was forced to seek an alternative means of escape at Sobrik Spaceport. In Hangar 61 of Sobrik Spaceport, she was confronted by a Sith Warrior, leading to a duel. During the fight, she proclaimed that Baras had already been defeated because the damaging information had been transmitted off-world. She entreated the Warrior to reject the dark side and seek redemption. However, the Sith ignored her plea and launched an attack. Mashallon defended herself, but despite her belief that the dark side weakened the Sith Warrior, her opponent proved stronger. At the mercy of the Sith, she accepted her impending death, content in the belief that she had dealt a significant blow to the Empire. However, Lieutenant Malavai Quinn of the Empire arrived with a squad of troopers, revealing that he had intercepted her transmission, thus keeping the Jedi Council unaware. Despite this setback, Mashallon asserted that Karr and his Padawan would ultimately defeat Baras and his apprentice. Following this declaration, the Warrior executed her.
Mashallon is a character that is not controlled by the player in the massively multiplayer online role-playing game Star Wars: The Old Republic, which was launched by BioWare in 2011. The voice acting for her character is done by Kath Soucie.
The player has the option to either eliminate Mashallon or give the order to apprehend her.