When Revan was first being trained as a Jedi Padawan, he was found to be very strong in the Force. His close friend Malak was strong in the Force as well, though Revan was undeniably the more powerful of the pair. Revan's first Jedi Master was Kreia, though he learned from several others, including Masters Zhar, Dorak, and Kae. But after learning from these Masters, he came back to learn more from Kreia. After the Jedi Civil War, Kreia was overcome with guilt and confusion about Revan's fall. She journeyed to Malachor V, where she was corrupted by the dark side, becoming Darth Traya.
Nearly 4,000 years before the events of Star Wars Episode IV: A New Hope, a warrior race known as the Mandalorians began raiding worlds on the edge of the galaxy. Despite Revan and Malak's belief that the Jedi should help the Republic, the Jedi Order insisted on staying out of the war, feeling that the true threat had not yet revealed itself. Many younger Jedi were unwilling to wait as the Mandalorians assaulted planet after planet, and so Revan and his friend Malak organized a force of rebellious Jedi Knights to assist the Republic in defeating the Mandalorians. Many Jedi felt inspired by the charismatic Revan, and so they joined him. The Mandalorians expected Master Kavar (an established general, and one of Revan's teachers) to lead the battle instead of him. Revan proved to be not only one of the most powerful Jedi in history, but also a master tactician and strategist. He was willing to sacrifice entire planets so as to make the most important ones impenetrable. And despite taking massive casualties (sometimes as many as ten Republic soldiers for every Mandalorian), Revan was consistently able to outmaneuver and overwhelm the enemy both in space and on the ground.
The final battle of the war took place at Malachor V, a cultural taboo to the Mandalorians. Revan sent his least loyal troops to lure the remnants of the Mandalorian fleet there, where a mass shadow generator had been placed. The general overseeing its use was the Jedi Exile, who gave the order to activate it. The result nearly destroyed the planet. Few on either side survived. Around the conclusion of the Mandalorian Wars, Revan fought Mandalore (the Mandalorian leader) in a grueling battle. Revan won, killing Mandalore, and thus struck a crippling blow to the Mandalorian war effort.
At Malachor V, Revan discovered the Trayus Academy, where he was supposedly corrupted by the teachings of the Sith. The planet itself was an ancient storehouse of the Sith; steeped in a darkness so great that it almost destroyed Revan. He was able to survive this darkness only by giving into the dark side of the Force. Taking the mantle of Dark Lord of the Sith, he began to corrupt other Jedi easily. Malak, now Darth Malak, grudgingly assumed the title of apprentice.
Alternately, it has been postulated (by his former Master Kreia) that Revan never fell to the dark side, but discovered a threat beyond the borders of the Republic for which the Jedi would be no defense, only the Sith. (Perhaps a foreshadowing of Grand Admiral Thrawn, who used similar tactics nearly 4,000 years later.) This is hinted at in the Sith Academy, when Yuthura Ban tells of the , prophesied to be slave to neither light nor dark side of the Force. That she tells of this prophecy directly to Revan would be incredibly ironic if one were to believe that Revan was the Sith'ari. According to both contexts (and being that they have both similar roles), it is commonly believed that Revan and/or Anakin Skywalker is the Sith'ari.
Afterhis corruption, Revan took ships beyond the known galaxy in search of an ancient artifact, a megastructure known as the Star Forge. For several years prior to the war, Revan and Malak had been researching artifacts in reference to this powerful Star Forge. They discovered that it was a massive space station with the ability to produce an almost limitless number of ships, accomplished by siphoning matter and energy from a nearby star as well as feeding on the dark side energies imbued within it. Revan and Malak, now beholden to the dark side, created a massive fleet to destroy the Old Republic and the Jedi, reforming the ex-Republic forces who followed them into a militaristic empire.
The reinvigorated Sith won battle after battle, until a young Jedi named Bastila Shan entered the fray with her Battle Meditation. This rare and powerful Force ability increased the combat effectiveness of the Old Republic's forces and sapped the will of enemy combatants. Even with this power, however, the Old Republic's forces knew that they could not hold out forever against the Sith. In a desperate attempt to endthe war, the Old Republic set a trap for Revan and Malak, during which Bastila and a team of Jedi boarded Revan's flagship and managed to corner the Dark Lord on the bridge. Thought by many to be the most powerful Sith Lord of all time, it is likely that Revan would have defeated Bastila and the remnants of her Jedi strike force. However, Malak, likely knowing he could not defeat Revan in personal combat, took this opportunity to kill both Revan and Bastila with one swift stroke. He fired upon the flagship from a nearby battle cruiser, but was successful in killing neither his master nor Bastila. Revan, nearly dead, was partly healed by Bastila Shan, creating a Force bond between the two. His mind was reprogrammed by the Jedi Council to hide the Dark Lord's old identity, while enabling the Jedi to use Revan's subconscious memories to locate the Star Forge and destroy it.
Revan was enlisted as a soldier in the Old Republic army and placed under Bastila's command on the Old Republic warship Endar Spire. Malak, thinking his master dead, devoted all his forces to the hunt for Bastila. In orbit over the world of Taris, the Endar Spire was attacked by a Sith fleet and destroyed. Bastila managed to escape to the planet's surface, followed soon after by Revan and fellow Republic soldier Carth Onasi. The Sith blockaded Taris, intent on capturing Bastila. They were unaware that the young female Jedi had already been taken prisoner by a swoop gang called the Black Vulkars, who intended to give her to the winner of an underground swoop racing tournament as a slave. Revan eventually succeeded in rescuing her when he infiltrated and won the tournament. In orbit, Darth Malak, deciding that the search for Bastila was taking too long, gave the order to destroy the entire planet. Positioning themselves in strategic formations, the ships of his fleet unleashed a devastating planetary bombardment that wiped out nearly all life on Taris's surface. Revan, Bastila, and Carth, along with their newfound crew, barely escaped in time aboard the Ebon Hawk, formerly the personal spaceship of the late Taris crime lord Davik Kang.
Revan and his companions fled to the Jedi stronghold of Dantooine, where Bastila convinced the Jedi academy council to retrain the amnesiac Dark Lord in the ways of the Jedi. After Revan completed his formal training, he and Bastila were sent to investigate an ancient stone structure. Inside, the two uncovered an ancient artifact known as a Star Map, a relic of the long-forgotten Infinite Empire of the Rakata. Though the Map was not complete, it pointed the way to the worlds of Tatooine, Kashyyyk, Manaan, and Korriban, on which more Star Maps could be found. Only with the combined information of these five worlds, Revan discovered, could the location of a mysterious Rakatan artifact called the "Star Forge" be found.
Revan, Bastila, and their companions journeyed to these worlds, tracing the steps Darth Revan and Darth Malak had taken years before. On each planet, the powerful dark side aura of the Star Maps had created perilous conditions that made access to the Maps difficult. Additionally, the crew of the Ebon Hawk found themselves hunted by Sith and bounty hunters, and confronted with the problems of the local populace at every turn.
After discovering the fourth Star Map (including the one found in the ruins on Dantooine), Revan and his allies were captured by the Sith flagship Leviathan. They managed to escape from their holding cells, but, as they fled toward the Ebon Hawk, Revan was confronted by Darth Malak, who revealed to him his former life as the Dark Lord of the Sith. A vicious lightsaber duel ensued, culminating with Bastila's capture by Malak. Revan was forced to deal with Malak's revelation and his loss of Bastila as the quest for the Star Forge stepped up, until at last it was found in the home system of the ancient Rakata.
After gaining the support of this race, Revan was forced to confront a fallen Bastila. Following weeks of torture at Malak's hands, Bastila had at last given in to her hate, or perhaps despair over her forbidden love for Revan, and had fallen to the dark side. She now claimed to be the Dark Lord's new apprentice. His original apprentice, a former Jedi named Darth Bandon, had previously been slain by Revan during the search for the Star Maps.
Atop an ancient Rakatan temple, Bastila attempted to entice Revan to reclaim his former title of Dark Lord of the Sith. This was the climax of the quest for the Star Forge, and it ended with Revan, once again, making a choice that would change the fate of the galaxy.
Revan made the choice of a Jedi, rejecting Bastila's temptation. Enraged, Bastila retreated to the Star Forge. Revan and the crew of theEbon Hawk pursued her as an Old Republic fleet commenced an assault of its own.
Aboard the Star Forge, Revan almost single-handedly defeated an entire army of Sith and Dark Jedi, a testament to his power in the Force and mastery of lightsaber combat. Near the end, he faced off against Bastila once again. After defeating her, he succeeded in convincing her to return to the light side by drawing on their love which had formed between them during the course of their quest. Bastila returned to the light and agreed to use her Battle Meditation to aid the Republic Fleet. The Old Republic fleet, now no longer hindered by Bastila's Battle Meditation, continued its bombardment of the Star Forge. Finally, Revan again confronted his old friend and apprentice, Malak, in an epic lightsaber duel. During their duel, Malak continually sucked the life force from Jedi held in stasis to replenish his energies. This, however, was not enough to defeat Revan, as he forcefully released the captive Jedi, allowing them to become one with the Force. At last, Malak was cut down. Before his friend's death, Revan apologized for starting him down the dark path, even though Malak had continued down it willingly. Malak accepted his apology, realizing that he had no one to blame for his fate save himself. Then Darth Malak, Dark Lord of the Sith, died, his life ending in darkness and regret, and the Star Forge was destroyed.
A mere year after the defeat of Malak and the collapse of the Sith Empire, Revan left the Old Republic, having recovered his memories regarding the remnants of the ancient Sith Empire he had discovered as the Dark Lord. Hoping to put an end to the threat it posed before it could attack the weakened Old Republic, Revan bade farewell to the nine comrades who had accompanied him on his quest, knowing that none whom he loved could safely accompany him in the places he had to walk.