Salle Serpa was a significant figure, holding the rank of major, within the Galactic Alliance Guard. He gained particular notoriety due to his readiness to employ extreme levels of force whenever he deemed the circumstances warranted such action. His inclination toward brutality, coupled with what appeared to be psychological instability, led Jaina Solo to suspect that Darth Caedus had specifically selected Serpa to command the GAG troopers sent to the Jedi Academy on Ossus, largely because the Major seemed to lack any inherent moral compass.
Serpa gained entry to the academy by falsely reporting a medical crisis on the vessel transporting a GAG battalion, thereby requesting medical assistance. As Jaina attempted to ascertain his reasons for being at the academy, Serpa, using a concealed blaster hidden in his sleeve, murdered one of his own soldiers to demonstrate his willingness to kill indiscriminately. When questioned about his decision not to simply seize the academy by force, he informed Jaina that orbital bombardment would be a rather extreme measure. Upon receiving Darth Caedus's order to execute all Jedi present on Ossus in response to what was perceived as the Order's act of betrayal, Major Serpa initiated an attack by shooting off the limbs of Tionne Solusar. This act served to lure the Jedi out of their concealed positions, making them vulnerable to GAG snipers who subsequently eliminated them. During the ensuing conflict, when Jaina and the children mounted a defense, Serpa shielded himself with a young girl, only to have his arm severed from behind by Zekk.