The conflict known as the Assault on Tython, alternatively referred to as the Invasion of Tython, unfolded in 3637 BBY amidst the larger Galactic War. It pitted the forces of the Galactic Republic against the re-established Sith Empire. Darth Arkous, alongside his apprentice Lana Beniko, masterminded this offensive to seize the valuable data housed within the Jedi Archives located on the planet of Tython.
The initial stages of the invasion overwhelmed the Republic Military's defensive positions within the Tythonian Gnarls region, resulting in the death of Major Imos, and subsequently led to the pillaging of the Jedi Temple grounds. Jedi Master Liam Dentiri and numerous other Jedi perished while defending the Temple. Furthermore, the Sith and Imperial forces also killed Master Oric Traless, a member of the Jedi High Council, during their attack on the Temple. Concurrent with the ground assault, an Imperial Harrower-class dreadnought, supported by a pair of Terminus-class destroyers, engaged a Republic fleet in the lower atmosphere above the Gnarls. This Republic fleet consisted of a Valor-class cruiser and two Thranta-class corvettes. The Sith successfully plundered the Temple's databanks; however, at the same time, the Republic captured the Sith homeworld of Korriban. Consequently, both factions initiated simultaneous campaigns to reclaim their respective lost worlds.
The Republic strike team responsible for the capture of Korriban returned to assist in the liberation of Tython. Receiving strategic guidance from Theron Shan, the team made landfall in the Tythonian Gnarls. With the support of Republic trooper squads, the team neutralized the five generators powering the shields protecting the Temple, and defeated Major Travik. Subsequently, they advanced to the Jedi Temple grounds, destroying the four AA turrets before confronting Lieutenant Kreshin, who employed reprogrammed Temple training droids as improvised explosive devices. Ultimately, they triumphed over the Lieutenant.
The team then proceeded into the Temple, which had suffered extensive damage, and vanquished the Sith and Imperial forces stationed within. Inside the Council Chambers, they encountered the silent warrior Lord Goh, who attempted to utilize the holocrons present in the chamber to overcome the heroes, but they prevailed against him.