A battle was fought at the Maelstrom early in the Galactic War between the Galactic Republic and the Sith Empire. The Jedi Master Oteg, a fleet admiral in the Republic Navy and commander of the First Expeditionary Fleet, had learned of a powerful Jedi who had been held as a personal prisoner of the Sith Emperor at a secret prison in the Maelstrom, and rallied an elite team to free him. After obtaining a Gree computer to travel the shifting expanse of the Maelstrom, the team infiltrated the base to free the prisoner while Oteg's fleet engaged the Imperial defenders in space.
Oteg had come in contact with the Force ghost of the slain Jedi Master Meetra Surik, who informed him that the Sith Emperor had held a Jedi prisoner for three centuries at a secret prison in the Maelstrom. Believing the prisoner to be a possible solution to ending the war before it escalated, Oteg called upon an elite team of Jedi, Republic soldiers and hired guns to infiltrate an Imperial fortress on Taral V in order to obtain a Gree computer, required to navigate the Maelstrom.
Using a captured Imperial shuttle, Oteg's strike team was able to enter the fortress and defeat both its Imperial garrison and the jungle beasts tamed to their will. As they claimed their prize, they were confronted via holocom by Grand Moff Rycus Kilran, commander of the Imperial Fifth Fleet and reviled by the Republic as the "Butcher of Coruscant." The Grand Moff ordered his ships to bombard the fortress to ensure the strike team could not escape, and indeed the team barely managed to escape back to Oteg's flagship, the Valor-class cruiser Telos, before Kilran's fleet obliterated the compound.
Having the Gree computer integrated into the navigational systems of the Telos, Oteg prepared to take the next step. Rallying his fleet, the Jedi Admiral ordered a course set for the Maelstrom. His ships would engage the station's defenses, while the strike team from Taral V would board the station itself and locate the Jedi prisoner.
Upon arriving at the station, the strike team boarded the base as planned. However, Kilran—one of the Empire's most brilliant military strategists—had made his way to the Maelstrom before Oteg's forces arrived, lying in ambush; with the team boarding the prison and breaking through its defenses, Kilran pinned Oteg's fleet between his warships and the station's defenses. Contacting the strike team in the station's security control room, Kilran gloated that Oteg had spread himself too thin, and remarked that Darth Malgus would be pleased at the result.
Oteg then contacted the team, knowing that as long as his ships stood between Kilran's fleet and the station, the team would be protected long enough to do their job. Knowing Oteg's fleet would be wiped out if they stayed, the team advised Oteg to make a fighting retreat out of the system while they proceeded through the station towards their objective.
After battling their way through the station's defenders—including captured beasts, battle droids, Imperial soldiers, and even several Sith—the Republic team made its way into the station's secured prison cell, where they came face to face with Kilran and a pair of bodyguards from his fleet. Kilran was in holoconference with Darth Malgus, who instructed Kilran that the Emperor's prisoner was to remain his top priority, not the attackers; Kilran replied that he could handle both problems in a single stroke. Kilran battled the Republic attackers using a customized sniper rifle with deadly accuracy, but despite his skill, he was no match for his opponents.
After defeating Kilran, the strike team approached the holding cell in the prison's core, holding a single figure in richly adorned robes. The team deactivated the holding cell, and the figure collapsed to the floor. Coming unsteadily to his feet, the Jedi momentarily panicked, demanding to know what the strike team had done. The Force ghost of Meetra Surik, who had revealed the prison's location and aided the strike team in the search, appeared before him, declaring that he had to be freed or all would be lost, and that the Emperor was drowning him in "black waters." The Jedi prisoner revealed himself to be Revan, a Jedi Knight and hero of the Mandalorian Wars. Discovering the Sith capital of Dromund Kaas after defeating the Mandalorians at Malachor V, Revan and his friend Malak had been corrupted by the Sith Emperor, returning to the Republic as Sith Lords. The newly minted Darth Revan initiated the Jedi Civil War and nearly brought the Republic to its knees; after losing his memory to a treacherous attack by Malak, Revan was taken back by the Jedi Order, redeeming himself by rallying the Republic and destroying Malak.
Revan revealed that he had gone with his allies after the Jedi Civil War to hunt down and destroy the Sith Emperor on his homeworld of Nathema, but was waylaid for years on Dromund Kaas, where he eventually confronted the Emperor. However, due to betrayal from within, Revan's allies were slain and Revan himself captured by the Emperor, held in unaging, unfeeling stasis by Sith sorcery. Revan and the Emperor were mind-linked throughout his imprisonment—the Emperor attempting to force the Jedi to submit to his will and become Darth Revan again, and Revan tempering the Emperor's hate, preventing him from striking against the Republic until the first Great Galactic War, some three centuries later, and convincing him that peace was in his best interest at that war's end. Now that the link was broken, Revan feared that the war would resume, but Meetra told him that the peace had already collapsed.
Fleeing from the Maelstrom, the heroes met with Revan again in the situation room on board the Telos. Revan was preparing to journey to Tython, the seat of the Jedi Order, to inform the Jedi High Council of the knowledge he had acquired during his three-century long imprisonment. Revan also revealed that there was one bit of information he was able to hide from the Emperor: the location of a space station known as the Foundry, a lost relic of the Rakata Infinite Empire. He bade farewell to his rescuers and urged them to return to the war, where their strength would be needed to defend the Republic. After meeting with the Council, Revan journeyed to the Foundry and began producing extermination droids—modeled on his first creation, the assassin droid HK-47—to destroy the Emperor and his followers. However, Revan was eventually hunted down and defeated by an Imperial strike team sent by Darth Malgus, and the Foundry fell into the hands of the Empire despite Revan's efforts.
Kilran's death resulted in the ascendancy of Grand Moff Ilyan Regus, long overshadowed by Kilran's career and reputation. As the war progressed, Regus would oversee the most crucial military operation since the Sacking of Coruscant: Operation Dark Ice.
The fate of Master Oteg is determined by the choice made just after the first holocall from Grand Moff Kilran in the prison's security center. The light side choice (implied to be canon) is to instruct Oteg and his fleet to fall back, allowing him to survive the battle and take part in the debriefing at the end of the "Jedi Prisoner" quest. The dark side choice is to instruct Oteg to fight on, despite the odds; during the debriefing, Revan reveals that Oteg was killed by a direct hit on the Telos' bridge.
- Star Wars: The Ultimate Visual Guide: Updated and Expanded