Rule of Two

The Rule of Two was preceded by the Doctrine of the Dyad, which was a concept centered on two Force-sensitive beings who had a unique Force-bond—that was unbreakable—which made them one in the Force called a Force dyad. Ancient legends referred to the dyad as the source of unique Force powers, such as Force healing, and the ability to transfer objects through the Force. The Doctrine of the Dyad was inscribed on the walls of the Sith Citadel, an ancient Sith stronghold located on the planet Exegol, to remind the Sith of the dyad's significance in their quest to attain ultimate power. The Sith Eternal, a cult of Sith loyalists, revered the Doctrine of the Dyad, believing that the dyad symbolized the future of the Sith and was the key to achieving the full potential of the dark side of the Force.

The concept of the Rule of Two, the relationship between a Sith Master and a Sith apprentice, was part of ancient Sith ideology since the time of the Great Scourge of Malachor. The masters demanded loyalty from their apprentices, but they sometimes betrayed them if they found one with more potential. In ancient times, the Sith were often ruled by two Sith while many others existed at the same time under them.

The Sith Lords were the ancient enemies of the Jedi Knights for millennia. Eventually, the Sith's greed for power caused them to turn on themselves, which allowed the Jedi to defeat and decimate the weakened Sith a millennium before the Clone Wars. Darth Bane emerged from the conflict as the sole surviving Sith Lord. With the Sith in a weakened state, the Jedi Order triumphed over the Sith on Ruusan. Realizing that the Sith's greed led to their destruction, Bane created the Rule of Two. The Sith thenceforth consisted of only two Sith Lords at any given time; the master who embodied the power of the dark side, and the apprentice who craved that power. Bane also created the Grand Plan, which was a revenge plot against the Jedi. The generations that came after Bane were able to operate in secret for centuries, contributing to Bane's plot that would see the Jedi's destruction and the restoration of Sith rule throughout the galaxy.

The Rule of Two as a philosophy was influenced by Bane's personal experiences as well as the study of ancient Sith documents. Under the Rule of Two, a Sith apprentice had to kill the Sith Master and take on an apprentice, in order to become the master themselves, which ensured that the Sith grew more powerful and cunning with each generation. On the other hand, the master could train another apprentice, and have them replace and kill their outgoing apprentice. As a result, the relationship between the master and the apprentice lacked trust, as both constantly searched for signs of weakness in the other.

Bane took an apprentice of his own, Darth Zannah, and passed on his knowledge while establishing the new Sith way of pursuing power and revenge against the Jedi through manipulation and subterfuge. The Jedi became aware of Bane's philosophy and Bane was killed. Although historical records weren't accurate, it was considered possible that Bane was killed by his own apprentice. The Jedi Order took responsibility for ending what Jedi Master Elzar Mann described as "the rule of Darth Bane." No matter the case, the Jedi went on to falsely believe that they had destroyed the Sith forever despite rumors that the Sith continued in the shadows.

However, Bane's plans continued through his apprentice, allowing the Sith to survive secretly for years while planning their revenge against the Jedi Order. Darth Sidious stated in his book, The Secrets of the Sith, that Bane was in fact killed by his apprentice. As a result, a cycle of betrayal and death became affixed to the Rule of Two, in which generations of apprentices fulfilled their training by killing their masters. The Rule of Two created a powerful dynamic by limiting the Sith to only one master and one apprentice at a time, although not all Sith followed the decree as some took apprentices of their own while still serving a master.

The Sith carried out their vendetta for a thousand years, gaining power in secret while the Jedi still believed that the Sith had been destroyed. During this period, the Dark Lord of the Sith Darth Plagueis took Darth Sidious, the Sith persona of Senator Sheev Palpatine of Naboo, as his apprentice. They worked for years to coax the final secrets from the dark side of the Force. Sidious called back on the wisdom of Plagueis as a planner and a prophet, knowing full well that two Sith were required to enact their means; one to serve as bait for the dark side, the other to be the vessel. Success would allow them the ability to harness the full power of the dark side and rule immortal for ten thousand years. Plagueis attempted to create a Force dyad with Sidious, which was a power as strong as life itself, which he discovered from the Doctrine of the Dyad, which was the predecessor of the Rule of Two. However, Plagueis was unable to form the dyad.

While training under Plagueis, Sidious acquired a Dathomirian Zabrak named Maul as his pupil. He had initially considered Mother Talzin, Maul's mother, to be his Sith apprentice, but took Maul upon realizing his potential. Seeing no further use for his master, Sidious betrayed Plagueis by killing him in his sleep. However, Sidious always saw him as not quite good enough, which he saw as the essential quality that defined Maul's life.

After killing his first Jedi, the Twi'lek Padawan Eldra Kaitis, Darth Maul reflected that she would have made a good Sith apprentice, but that he had to finish her off to prevent his master from discovering his intended betrayal. Concurrently, Xev Xrexus from the Xrexus Cartel theorized the Sith's comeback, leading Maul to kill her as Sidious had threatened him with death if they were prematurely discovered.

In 32 BBY, during the Invasion of Naboo by the Trade Federation, the Sith finally revealed themselves to the Jedi with Sidious sending Maul to Tatooine to capture Queen Padmé Amidala and take her back to Naboo so she could sign a peace treaty. The Jedi Qui-Gon Jinn faced Maul but was able to leave Tatooine with Amidala and his allies, realizing that the Sith had returned. During the Battle of Naboo, which broke the Federation's blockade, Maul killed Jinn only to be seemingly killed in turn by Padawan Obi-Wan Kenobi, leading the Jedi to realize the return of the Sith. During Jinn's funeral, both Yoda and Mace Windu, the Grand Master and Master of the Order of the Jedi respectively, pondered on who could be the other Sith Lord due to the Rule of Two demanding only two Sith and whether Maul was the master or apprentice of the Sith pair that had just been reduced to one. Though Maul would later turn out to be alive, Sidious turned his gaze away and lost all interest in him.

With Maul presumed dead, Sidious took the former Jedi Master Count Dooku from House Serenno as his next apprentice and bestowed him the name Darth Tyranus. Sidious had actually approached Dooku while still apprenticing Maul, and met with Dooku in a skyscraper of his after Maul's loss on Naboo to assure him that the deaths of their apprentices were in service of their goals upon being called out for allowing Maul to kill Jinn, whom Dooku felt could have been a great ally to them despite Sidious not thinking the same. Unknown to the Sith, Jedi Master Yaddle had followed Dooku there, but at Sidious' prompting, Dooku finished Yaddle off to prevent her from alerting the Jedi, officially cutting any ties he still had with the Jedi and becoming Sidious' pupil. During a mission on Sullust, Dooku considered recruiting the Jedi Knight Jak'zin as an ally to the Sith cause, but ultimately stopped when Sidious stated that a Sith Master needed only one apprentice and threatened to replace him with the Togorian Jedi. Dooku ensured that Jak'zin was killed, though he lamented that his death was a pity.

During the next decade, Dooku aided his master in engineering the Clone Wars, including orchestrating Jedi Master Sifo-Dyas' death, and then to use his name to order an army of clone troopers to be created for the Republic and selecting bounty hunter Jango Fett as the genetic template for the clones. They also had biochips implanted in the clones' brains, which unbeknownst to all but Sidious and Dooku, would allow Sidious to force the clones to destroy the Jedi through his secret protocol, Order 66. In 22 BBY, with the Confederacy of Independent Systems on their side, Dooku revealed his new allegiance to the Jedi and the Clone Wars began with the First Battle of Geonosis.

Throughout the conflict, the Rule of Two was violated by Dooku, who took the Dathomirian Nightsister Asajj Ventress on as an assassin and apprentice. However, Sidious, believing Dooku may have been training her to destroy him and sensing that her power had grown, ordered Dooku to eliminate her. Dooku obeyed his master and left her for dead following the Battle of Sullust. Dooku later took the Zabrak Savage Opress, brother of Maul, as his apprentice so he could take Sidious' place as master only for his plan to fail due to Ventress' intervention. Upon receiving a premonition of events to come, the Besalisk Jedi Master Pong Krell fell to the dark side in an attempt to become Dooku's new apprentice, but the clone Dogma executed him after Krell turned on the 501st Legion. However, Dooku took the Jedi Master Quinlan Vos as his apprentice after capturing him, but his plan failed again as Ventress gave her life to save Vos.

Opress tracked his lost brother, Darth Maul, to the planet Lotho Minor in 20 BBY and subsequently brought him to Dathomir, where Mother Talzin used magick to restore Maul's mind and repair his body. Although he was no longer apprenticed to Darth Sidious, Maul still claimed the mantle of Sith, and therefore, assumed the role of master with Opress as his apprentice. Maul regarded Darth Tyranus as a "Sith pretender" and claimed to be the "true" lord of the Sith alongside his brother.

Following his secret takeover of Mandalore, Maul was confronted by his former master in 19 BBY. Despite Maul's assertions of attempting to regain his place at Sidious' side, the Dark Lord sensed deception and acknowledged his former pupil as a rival. Sidious fought alone against the Dathomirian brothers, and ultimately killed Opress before subduing Maul, whom he reminded of their order's rule stipulating that only two Sith could exist at any given time. As such, Sidious denounced Maul's claim to the title of Sith, having replaced him with another apprentice.

By 3 BBY, Maul had abandoned his claim as a Sith and even discarded the title of "Darth," although he still drew power from the dark side of the Force and took refuge in a Sith temple of Malachor. When the Spectres rebel crew and the former Jedi Ahsoka Tano ventured into the temple, Maul tried to to take Kanan Jarrus' Padawan Ezra Bridger as his apprentice just to take revenge on all his enemies, but Bridger resisted. At one point, Maul discovered the location where an ancient Sith Lord was sealed away by the Fermata Cage and attempted to free them so they could kill Sidious and Vader for him in accordance to the Rule, but his attempts were unsuccessful. His quest for revenge culminated in Maul's death on Tatooine, where the former Sith Lord was killed by his nemesis, Jedi Master Obi-Wan Kenobi, in 2 BBY.

In 19 BBY, shortly before the end of the Clone Wars, General Grievous kidnapped Palpatine, which was a plan orchestrated by Sidious, in order to bring Anakin Skywalker to the dark side and replace Dooku as his next apprentice, as Sidious felt it was time to make Anakin his apprentice and that Dooku's purpose had been served. Palpatine's capture led to Kenobi and Skywalker to be dispatched to rescue him aboard the Invisible Hand. During a lightsaber duel aboard the ship, Skywalker defeated and disarmed Dooku. Sidious then betrayed his apprentice by encouraging Anakin to kill the Sith Lord, paving the way for Skywalker to take the older man's place. After Dooku's death, Sidious and his Jedi rescuers eventually made it back to Coruscant. Studentless again, Sidious seduced Skywalker to the dark side by telling him about Plagueis upon discovering his fears that Amidala, his secret wife, would die in childbirth. Skywalker initially revealed Palpatine's secret to Mace Windu, who then attempted to arrest the Chancellor. Skywalker, however, turned on the Jedi to save Palpatine from being killed, leading to Windu's death.

No longer a Jedi, Skywalker became Sidious' new apprentice and was anointed as Darth Vader. Sidious issued Order 66, causing the biochips to activate and brainwash the clone troopers into betraying and murdering their Jedi Generals, while Vader purged the Jedi Temple on Coruscant under Sidious's order. No longer requiring the Separatist Council, Sidious betrayed them by having Vader execute them. Sidious then framed the Jedi for treason and proclaimed himself Galactic Emperor, reorganizing the Republic into the First Galactic Empire. Kenobi and Yoda resolved to destroy the Sith, including the former Anakin Skywalker. However, neither Sith Lord was destroyed.

Sidious survived his battle with Yoda who subsequently fled into exile. Vader sustained grievous injuries in his duel with Kenobi, and was rebuilt as a cyborg encased within life support armor. After learning of Amidala's death and being told by Sidious it was his own doing, Vader lashed out in anger against his master but ultimately relented, agreeing to begin his new life. While bleeding his new kyber crystal, it showed him a vision of returning to the light, killing Sidious, and reuniting with Kenobi, but Vader rejected any such future, declaring his new reality was all that was left for him.

Vader still struggled with his sentiment for Amidala, but he finally fully committed himself to the Sith following the Battle of Fortress Vader and a failed effort to revive her. Having not heard any word from Vader over the course of that incident, Sidious began considering that he would need to search for another apprentice. Once Vader finally contacted him again, Sidious claimed he would desist from seeking another apprentice. One part of the battle had also seen the ancient Sith Lord Darth Momin, who had kept his essence alive via his mask, resurrect himself and mock the modern Sith as a weak, Jedi-obsessed order. In their duel, Vader ultimately killed the ancient dark side user.

Sidious also tried to create a dyad with his own apprentice, Darth Vader. Yet, even with the Chosen One at his side, Sidious was unable to form the dyad. He started to doubt if a dyad was possible at all if the two most powerful bloodlines in the galaxy—Palpatine and Skywalker—could not produce such a bond.

During the Imperial Era, Vader taught the Inquisitorius, a group of former Jedi who had turned to the dark side, and were tasked with hunting down the remaining Jedi, though the Inquisitors themselves only served the Sith and were not considered Sith apprentices, being mere dark side adepts. By the time of the Battle of Yavin in 0 BBY, the Inquisitorius had ceased to exist. Vader did once ponder if the the Grand Inquisitor would have taken his place should he had lost their duel in the former Jedi Temple, but he quickly assured Sidious there was never a chance of him losing that encounter.

The New Order was put in danger when the Alliance to Restore the Republic succeeded in destroying the DS-1 Death Star Mobile Battle Station at the Battle of Yavin. In the aftermath of the Death Star's destruction, Doctor Cylo presented the Emperor with several bioengineered warriors—Commander Karbin, Tulon Voidgazer, twins Morit and Aiolin Astarte and a Trandoshan—as replacements for Vader. The scientist considered Vader a ceremonial apprentice, and therefore believed that his cybernetically enhanced creations were superior to the Sith Lord.

Vader regarded Cylo's work as heresy, his creations as abominations; however, the Emperor chastised Vader who was also a cyborg. He reminded Vader that, as an apprentice, it was his duty to learn rather than preach doctrine. By then, Vader had lost favor with his master who blamed him for failing to save the Death Star.

Vader, however, eventually proved himself to his master and killed each of Cylo's creations and Cylo himself. Sidious had reflected on the triumphs of the Sith by then, from their survival as an order to the fall of the Jedi and the rise of the Galactic Empire. He recounted that it took generations before the Sith could return to power through him. He also remembered his former apprentices, Darth Maul and Darth Tyranus, and considered them tools in his ascension to ultimate power. He credited Vader as his ideal apprentice, but Vader dismissed the Emperor's words as false flattery, believing that Sidious would have made a similar speech to any of Cylo's warriors had they succeeded in defeating him.

Upon learning the existence of Luke Skywalker, Vader's secret son and the Rebel pilot who destroyed the Death Star, both made plans to use Luke to overthrow each other. Vader desired for Luke to help him overthrow Sidious, so the two could rule the galaxy. Sidious, on the other hand, planned to have Luke kill Vader and then replace him as Sidious's apprentice. While trying to recover the Emperor's respect before Cylo's death, Vader became aware of his parenthood after the bounty hunter Boba Fett discovered the pilot's name and informed Vader of this. Focused on trying to get his son to join him on the dark side, Vader killed Karbin and prevented Luke from being captured on Vrogas Vas.

In 3 ABY, following the Battle of Hoth, Vader communicated with Sidious aboard the Executor, as the Emperor had sensed the threat Skywalker posed to the Sith. Promising his master that Skywalker would either choose joining them or be killed by his hand, Vader managed to capture the crew of the Millennium Falcon on Cloud City and manipulated Luke into saving his friends.

Upon arriving on Cloud City, Bespin, Skywalker was unable to hear Leia Organa's warnings that Vader had set up a trap for him. Skywalker then found Vader and the two engaged in a duel. Vader defeated his son by severing Skywalker's right hand before telling him that he was his father. Vader then offered Skywalker the chance to join him and overthrow the Emperor and bring order to the galaxy. Skywalker, however, refused and plunged himself into the shaft only to be rescued by the Falcon.

In the aftermath of his failure to bring his son to the dark side, Vader unearthed some secrets about Amidala's death before the Emperor summoned him to the Imperial Palace. Believing that Vader had regressed from a powerful Sith Lord to a grief-stricken widower, Sidious destroyed his apprentice's cybernetic limbs before leaving him on Mustafar as test of Vader's resolve to survive. He also sent his Sith assassin, Ochi of Bestoon, to test Vader's abilities without relying on the Force.

Vader rebuilt himself, captured Ochi and traveled to the hidden Sith world of Exegol to discover the Emperor's plans. Finding Sidious there, Vader mocked Sidious' title as his master and declared himself to no longer be his apprentice. Following Sidious into the Sith Citadel, Vader and Ochi discovered the Emperor's creations as well as his acolytes. Though none of them were Sith, Sidious declared that they all had the potential to replace Vader.

Vader killed the Emperor's servants, but was ultimately overpowered by Sidious who used a mountain of kyber crystals as a display of the unlimited power in his possession. He discovered the construction site of a massive reserve of Xyston-class Star Destroyers armed with planet-destroying cannons. He inflicted pain on the kyber, a living entity connected to the Force, in accordance with the traditions of the Sith. As Vader felt the crystals' pain through the Force, Sidious issued an ultimatum to him—to share in his power, but as an apprentice once more. Ultimately, Vader returned to his master's side after experiencing a vision of his son, Luke Skywalker, telling him that he could destroy the Emperor. Concluding that there was no room for another and having witnessed the true might and purpose of the Sith, despite knowing that Luke could still be strong, Vader felt that he had no other choice than to eventually kill his son despite, ultimately, still wishing Skywalker had joined him on Cloud City, just as he still wished Amidala would have joined him on Mustafar.

In 4 ABY, both the Empire and the Rebel Alliance were preparing for a definitive showdown above the Forest Moon of Endor with the second Death Star's superlaser finally operational. Still determined to find his son and having given up on the idea he needed to kill Skywalker, Vader was sent by his master to Endor to wait for Luke to come to him. After Luke turned himself over to Vader, Luke attempted to turn Vader back to the light side of the Force. Vader refused his son's pleas and the two traveled to the Death Star where Sidious awaited.

Once in the Emperor's Throne Room, the Emperor welcomed Skywalker, promising to complete his training, yet Luke affirmed the Emperor to be gravely mistaken and that he would not be turned like his father. Eventually a duel broke out between Luke and Vader, ending with Luke cutting off his father's hand. Sidious, who betrayed Dooku to gain Anakin as an apprentice, tried to replace Vader by having Luke kill his own father. Luke spared Vader's life, however, and declared that he had become a Jedi like his father before him.

Sidious attacked Luke in anger, using Force lightning to attack the Jedi for refusing to join him. Moved by his son's compassion, Vader returned to the light side as Anakin Skywalker and prevented Luke's death by throwing his master into a reactor shaft, killing Sidious and sacrificing himself in the process. This final act of sacrifice redeemed Anakin who died peacefully, restoring balance to the Force as the prophesied Chosen One.

Around 9 ABY, the Hunters of the Outer Rim competition would see a Force-sensitive named Rieve join its roster under the persona of a Sith Lord. While in private she was on good terms with her fellow hunters, her public persona saw use in HoloNet-streamed matches against other competition members. After Rieve won a match against her on-stage rival, the Jedi focused droid J-3DI, Arena News ran a story about her victory and included a reference to the Rule of Two as a fun fact. While unsure what the Rule of Two even was and admitting as such in the report, Arena News guessed it saw Sith carry twice as many lightsabers as a Jedi or was about a Sith needing to act twice as villainous as those who came before them. In the end, Arena News was hopeful that, one day, the truth behind the Sith edict would be revealed.

The deaths of Sidious and Vader ended the Sith lineage that dated back to the creation of the Rule of Two. But while the Sith's destruction was foretold in the Jedi prophecy of the Chosen One, it did not mean the end of the dark side of the Force. Sidious had observed the Rule of Two to the extent that it limited the Sith ranks to a master and an apprentice; beyond that, he was unwilling to be replaced and therefore sought to rule the galaxy forever as an immortal Sith Lord. Using the knowledge he gained from his late master, Plagueis, Sidious resurrected himself in a cloned body. The transference was flawed, however, and Sidious found his spirit tethered to a weak, decaying vessel. Sidious regarded the dyad as the key to the ultimate power coveted by all Sith; as such, he considered the Rule of Two a "pale imitation", an unworthy but necessary successor to the Doctrine of the dyad.

Aided by the Sith Eternal, the revived Emperor oversaw the continuation of the Contingency from Exegol, where a massive invasion fleet was built to enforce his future Sith Empire. Sidious also sought a new apprentice to train; the grandson of Vader and nephew to Luke Skywalker, Ben Solo's strength with the Force was prodigious as a result of his Skywalker bloodline. Through the Force, Sidious secretly communicated with Solo in order to lure him away from the Jedi path, undermining Skywalker's plan to restore the Jedi Order. Rather than directly training Solo, he created Snoke—an artificial strandcast—through whom he could mold the Skywalker heir into a servant of the dark side. The Sith Eternal were also involved in the creation of Snoke, whom they designed to groom Solo as an heir worthy of claiming the Sith legacy.

With the destruction of the Jedi Temple of Luke Skywalker, Sidious' efforts to turn Solo to the dark side of the Force succeeded as the fallen Jedi apprentice joined the Knights of Ren by killing their leader. Adopting the persona of Kylo Ren, he became the master of the Knights of Ren as well as the apprentice of Supreme Leader Snoke who ruled the First Order, a successor to the Galactic Empire. While neither Snoke nor Ren claimed the title of Sith, and instead represented a new generation of dark side wielders, they were nonetheless influenced by Sidious who remained hidden on Exegol.

Although Snoke had trained other apprentices before Ren, he regarded Ren as his most promising student. Snoke believed that as part of the Skywalker bloodline, Ren had the right balance of the dark side and the light in him due to his heritage as Darth Vader's grandson. Following a visit to the Cave of Evil on Dagobah, Ren reassured Snoke that he would not need other apprentices.

Thirty years after the defeat of the Sith, Ren assassinated Snoke in an act worthy of the Rule of Two. Ren subsequently gained the power and independence he coveted as the First Order's new Supreme Leader, and vowed to never return to serving powerful masters like Luke Skywalker or Snoke. In destroying his master, Ren had passed the final test in his training, achieving ascendance through his full submission to the dark side. Snoke's reason for existing had also been fulfilled; by using the former Supreme Leader as a proxy, Sidious circumvented the Sith tradition that required the apprentice to ascend by killing the master who trained him.

A year after the Battle of Crait, Sidious broadcasted a message announcing his imminent return. Deeming the phantom Emperor a threat to his rule, Ren obtained Vader's wayfinder and tracked Sidious to Exegol. The Emperor revealed himself as the source of all the voices in Ren's mind, including Snoke and Vader. He offered to help Ren succeed to the Throne of the Sith as the galaxy's new Emperor in exchange for killing his granddaughter, the Jedi apprentice Rey.

Rey confronted her grandfather after learning about their connection. During the Battle of Exegol between the Resistance and the Sith Eternal, Sidious urged Rey to submit to the dark side by sacrificing him, freeing his soul from its temporary vessel and allowing Sidious to possess Rey. However, she rejected him with the help of the redeemed Ben Solo, causing Sidious to unleash his power against the prophesied Force dyad. The power of their Force-bond restored Sidious' body, and he resolved to rule alone as Emperor once more. Empowered by the spirits of the past Jedi, Rey sacrificed herself to destroy the Emperor in body and soul, and with his destruction, Darth Bane's long lasting vendetta and the return of the Sith were aborted.

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