History Main / RuleOfTwo

* ''VideoGame/RocketKnight'': Regardless of whoever is the BigBad, they'll always have [[TheRival Axel Gear]] (the series' sole recurring villain) as their right-hand man.

-->-- '''Master Yoda''', ''Franchise/StarWars'' Episode I: ''Film/ThePhantomMenace'', about the Sith

--->'''Palpatine''': There are only two, and you are ''not'' my apprentice!

** Both of the CoDragons in ''Series/HikariSentaiMaskman'', Igam and Baraba, each have {{ninja}} bodyguards Fumin and Oyobu as their own personal henchmen respectively.

* ''VideoGame/MetalGear'': Similar to Star Wars above, there is only one Boss (Master), and one Snake (Apprentice). Big Boss was once Naked Snake, and his master was the #1 heroine of WWII, The Boss. Then she went rogue, he had to kill her and take the Boss title, which he wasn't happy about. But in a plot twist of epic proportions, [[spoiler:Solid Snake was never the apprentice - that was Venom Snake, Big Boss' body double and second-in-command. Snake killed the body double without realizing, and then set the master on fire.]]

[[folder:Film]]

* In ''ComicBook/StarWarsLegacy'', [[BigBad Darth Krayt]] does away with the Rule of Two, abandoning the Sith's SocialDarwinist tenets and instead teaching his followers the Rule of One which revolved around blind obedience to him and the Order. At one point he [[SpiritAdvisor communes with the spirits]] of the three greatest Sith Lords, seeking advice; Darth Andeddu, the progenitor of all Darths, [[VideoGame/KnightsOfTheOldRepublicIITheSithLords Darth Nihilus, who led the First Jedi Purge]], and Darth Bane, the Sith ChosenOne who created the Rule in the first place. All three of them then proceed to absolutely ''[[TheReasonYouSuckSpeech lay into him]]'' (even TheUnintelligible Nihilus), branding him [[TheHeretic a heretic unworthy of calling himself Sith]] for arrogantly trying to "improve upon" the teachings that [[Film/RevengeOfTheSith led to them conquering the galaxy]] and weakening them as a whole by attempting to share power. Krayt tries to argue that [[VillainHasAPoint power is meaningless without a purpose to apply it toward]], only for Bane to angrily retort that [[DespotismJustifiesTheMeans power is its own reward]] and that he's simply [[ChronicBackstabbingDisorder repeating the same mistakes he tried to prevent]].

* ''Franchise/StarWars'' is the TropeNamer. The Sith have the Rule of Two, where there can only be a Sith master and an apprentice - no more, no less — one to possess power and the other to desire it. The idea is that each Sith Lord teaches one apprentice until they are strong enough to destroy the master and take their place, at which point the apprentice will take on a student of his own, or until the master kills the apprentice and gets a new one. In this manner, each master not only ''becomes'' strong, but must ''stay'' that way to stay alive, and each student must become stronger than their master. A master cannot have more than one apprentice, because they may team up to kill their master despite being individually weaker than he or she, then turn on each other and weaken the Sith Order. In short, ChronicBackstabbingDisorder as a way of life and a code of morality. (Although this didn't always work, because it was shown with Sidious, he killed his master while he was sleeping.)
** The origins of this rule are first explained in the ''Film/RevengeOfTheSith'' novelization, and explored further in ''Literature/DarthBane''. When the Sith order was originally created, it was indeed an order that had many members, but since they were all steeped in the dark side, they had a collective bad case of ChronicBackstabbingDisorder. This tendency to betray each other at the drop of a hat weakened the order to the point where the Jedi ([[SanityHasAdvantages who as light-siders were more unified]]) were gaining the upper hand. Eventually, it all came to a head and a GambitPileup gone horribly wrong left a single survivor, Bane. To combat this, Bane decided that there should only be two Sith Lords at one time - a master to have power and an apprentice to covet it. He also decided that they should endeavor to take over the galaxy via subtlety and manipulation (like Palpatine eventually did) instead of outright invasion. [[spoiler: Having made up his mind on this, he manipulates all collectivist Sith Lords into committing mass suicide.]]

** Since ''WesternAnimation/StarWarsRebels'' has canonized the Imperial Inquisition, they are Dark Side Force-sensitives employed by Darth Vader, but are immune to the Rule of Two because they are not Sith. They're purposely trained so as not to reach the Siths' power level as they would run the risk of violating the rule like Asajj Ventress did.[[note]] However, this resulted in the Inquisitors having significant weaknesses of their own: since they were trained to not reach the power level of a true Sith, they're able to take out Jedi that were isolated or weak enough to not in the path of Order 66, but when confronted by prepared and skilled Force-users such as Kanan, Ahsoka or Maul, the Inquisitors are usually defeated quite handily. [[/note]]

*** Conversely, Palpatine began to suspect that Dooku was plotting the same in ''WesternAnimation/StarWarsTheCloneWars'' with his own assassin, [[DarkActionGirl Asajj Ventress]], and ordered him to have her killed to prove his loyalty. Dooku followed through with the order but failed to have her killed, resulting in her turning on him.

* This is a recurring motif in ''VideoGame/{{Touhou}}''.

** For that matter, the yin-yang features heavily in ''VideoGame/{{Touhou}}''; it's even one of Reimu's attack mode.
* ''Franchise/MetalGear'': Similar to Star Wars above, there is only one Boss (Master), and one Snake (Apprentice). Big Boss was once Naked Snake, and his master was the #1 heroine of WWII, The Boss. Then she went rogue, he had to kill her and take the Boss title, which he wasn't happy about. But in a plot twist of epic proportions, [[spoiler:Solid Snake was never the apprentice - that was Venom Snake, Big Boss' body double and second-in-command. Snake killed the body double without realizing, and then set the master on fire.]]

* In ''ComicBook/StarWarsDarthVader'', Emperor Palpatine explains that the master/apprentice arrangement was brought about because the last time the Sith fought the Jedi, they lost because [[WeAreStrugglingTogether they spent more time fighting each other]], so this way the competition is kept to a manageable level. However he's lost confidence in Vader after the destruction of the Death Star, so a large part of the plot involves Vader competing with other rivals for the role. When Palpatine claims that Vader's victory over these rivals was AllAccordingToPlan, Vader sardonically replies that if any of the others had won, Palpatine would be telling them the same thing.

* Just about every BigBad in ''Franchise/BigBad'' has a [[TheDragon right-hand]] of some sort. Some have [[CoDragons two or more]] though usually one of them will end up taking the lead.

It's usually understood that the two want to keep it that way. Never introduce a third, and quickly replace the other if they go down. Due to infighting or general ForTheEvulz culture, the BigBad may [[YouHaveOutlivedYourUsefulness decide to dispose]] of {{the Dragon}} himself and get a new one. Similarly TheDragon will [[TheUsurper overthrow]] the BigBad if the opportunity presents itself, and bring on a new Dragon of his own. The tension of this dynamic is that they rely on each other, but both know it's a race to see who will stab who in the back first.

** The rule didn't make it intact through Bane's own lifetime. By the time his apprentice confronted him he had already taken a second, and she had started training one of her own. Zannah's apprentice ended up wandering off and doing his own thing as a Dark Side user who isn't ''technically'' a Sith.

* In the job world, combined with RuleOfSeven in that if you quit, you're required giving 2 weeks (2 x 7 = 14 Days) notice.

** Ultimately Darth Bane's philosophy, while it kept the Sith alive in secret for millennia, also resulted in the order's undoing, as the chain could be easily broken by a factor that Bane failed to take into account-[[EvilCannotComprehendGood the potential redemption of either the master or the apprentice]]. Darth Vader's RedemptionEqualsDeath and, in the old ExtendedUniverse, Jacen Solo/Darth Caedus' apprentice renouncing the Dark Side of the Force and the Sith shortly after the former's demise, pretty much spells the end for the Sith Order ''because'' of the Rule of Two. What's worse is that Bane really should have known better. The Sith Lord whose Holocron gave Bane the inspiration for the Rule of Two, Darth Revan, had also renounced the Dark Side, and Bane knew this.

[[/folder:Real Life]]
* In the job world, combined with RuleOfSeven in that if you quit, you're required giving 2 weeks (2x7=14 Days) notice.

[[/folder]]

* ''Franchise/StarWars'' is the TropeNamer. The Sith have the Rule of Two, where there can only be a Sith master and an apprentice - no more, no less — one to possess power and the other to desire it. The idea is that each Sith Lord teaches one apprentice until they are strong enough to destroy the master and take their place, at which point the apprentice will take on a student of his own, or until the master kills the apprentice and gets a new one. In this manner, each master not only ''becomes'' strong, but must ''stay'' that way to stay alive, and each student must become stronger than their master. Each generation of Sith is stronger than the last, because any weak link in the chain is dead. A master cannot have more than one apprentice, because they may team up to kill their master despite being individually weaker than he or she, then turn on each other and weaken the Sith Order. In short, ChronicBackstabbingDisorder as a way of life and a code of morality.

* In ''ComicBook/StarWarsDarthVader'', Emperor Palpatine explains that the master/apprentice arrangement was brought about because the last time the Sith fought the Jedi, they lost because [[WeAreStrugglingTogether they spent more time fighting each other]], so this way the competition is kept to a manageable level. However he's lost confidence in Vader after the destruction of the Death Star, so a large part of the plot involves Vader competing with other rivals for the role. When Palpatine claims that Vader's victory over these rivals was AllAccordingToPlan, Vader sardonically replies that if any of the others had one, Palpatine would be telling them the same thing.

* In ''ComicBook/StarWarsDarthVader'', Emperor Palpatine explains that the master/apprentice arrangement was brought about because the last time the Sith fought the Jedi, they lost because [[WeAreStrugglingTogether they spent more time fighting each other]], so this way the competition is kept to a manageable level.

* In ''StarWarsDarthVader'', Emperor Palpatine explains that the master/apprentice arrangement was brought about because the last time the Sith fought the Jedi, they lost because [[WeAreStrugglingTogether they spent more time fighting each other]], so this way the competition is kept to a manageable level.