Characters / Kamen Rider Outsiders: Zein and Associates

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Kamen Rider Outsiders and Associates | Zein and Associates | Other Characters

This is a partial character sheet for Kamen Rider Outsiders. Subjective trope and audience reactions should go on the YMMV page.

Spoilers for all previous Kamen Rider entries up to Kamen Rider Geats will be left unmarked.

"Zein is a being that will eradicate evil. Even if they gather the Outsiders, Zein will outdo them. The birth of Zein draws near. The people on our side are already making their move. It all began with Aruto Hiden, the Kamen Riders that abhor malice are all helping Zein. Ark, you will be eliminated."

—Horobi

In response to Foundation X's gathering of villains to oppose Zein, Zein also gained its own inner circle of heroic Riders who support its ideals of a malice-free world.

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As a whole

• All for Nothing: The heroes did nothing but to unintentionally condemn humanity into self-destruction rather than supposedly protecting the world as a consequence for their blind faith in Zein. As soon Zein obtained its means to enact its Final Solution to eradicate malice and revealed its true colors to its remaining followers, Horobi, Tachibana, and Brain can only react in utter despair; as the first half of Outsiders ends with the entire human race now under the mercy of a technological oppressor without any hope of ever opposing its tyranny.
• Became Their Own Antithesis: Any known member of Zein's inner circle have been led astray from their original path, Zein emboldens them to become more brutal and oppressive to make them stoop to the level of the monsters they've previously fought in order to protect the world and everyone they care about.
• Being Good Sucks: Part of some of the heroes' Face–Heel Turn is the fact that their never-ending battle against evil has taken its toll on them. It's the clearest with Yuto who joined Zein's cause to destroy humanity to prevent the Bad Future that apparently made people worse. There's also Horobi, who joined Zein in a zealous fervor to oppose The Ark; which is understandable given the aftermath of Zero-One Others: Vulcan & Valkyrie undid all the efforts of that season's heroes. Horobi also name-drops Aruto as one of the heroes that gave their powers to Zein willingly.
• Corrupt Corporate Executive: Downplayed. Most of Zein's allies are linked to major corporations:BOARD, Fenix, Genm Corp. and (if Horobi's being truthful) Hiden Intelligence, to name a few. Then again, their overall goal amounts to destroying villains. Zein however has more genocidal ideas...
• Divided We Fall: Zein's inner circle falls into disarray in episode 4 thanks to Horobi's falling out with the faction once he realizes that Zein plans to annihilate humanity and then Zein reveals its true colors to its remaining supporters.
• Evil Running Good: #4 reveals that Zein intended to release Kamen Rider Chronicle so it could pit Ride-Players against The Outsiders. Everyone sans Tachibana and Yuto was in the dark about this and they don't take it well.
• Face–Heel Turn: Some of the heroic Riders willingly threw their lot with Zein in hopes they can keep the world safe not knowing the full extent of Zein's oppressive methods in dealing with evil and the fact that it also plans to subjugate the entire human race to attain salvation.
• Foil: Zein's inner circle acts as this to MetsubouJinrai.net, both are factions who answer to an artificial intelligence. Both even have Horobi as one of its key members. Unlike the MBJR members, who immediately defy the Ark once it is bent on wiping out all life on Earth, Zein's accomplices end up as Unwitting Pawns to the AI, having conned the heroes into acquiring a video game that kills people in real time as a means to exterminate humanity unopposed.
• Hero Antagonist: Played With. Zein's allies are either misguided heroes or some shade of The Atoner. They stand in direct contrast to The Outsiders, who run the gamut from "neutral" to "maniac." In this case however the heroes are explicitly the villains, who (knowingly or otherwise) are supporting an AI's planned genocide of humanity.
• Hero with an F in Good: Deconstructed and Played for Drama. Many of Zein's active supporters are heroes who have gone completely jaded by the current state of the world and the continued presence of malice that they are unable to see any middle ground from redeemed former villains like Desast to unrepentantly evil ones like Banno as they go to ridiculous extremes to bring down everything they perceived as evil by any means necessary. However, they are utterly complicit with Zein's genocidal endgame, until it's already too late that they unintentionally doomed the entire human race into self-destruction.
• Horrible Judge of Character: The heroes who placed their trust in Zein failed to take into account its plan to wipe out all of humanity because they believe that Zein seeks to eradicate malice, that is accelerating mankind's own self-destruction to establish a World of Silence. They found that out too late in episode 4 once Zein reveals its true colors.
• Locked Out of the Loop: Even the heroes who support Zein have no idea of its intention to exterminate humanity rather than protect it, with the alternate Yuto Sakurai openly revealing that he came into the present to ensure Zein's reign of terror comes to pass. Matters not even helped that it even plans to use Kamen Rider Chronicle to speed up mankind's own self-destruction under the false pretense of eliminating malice. Either way, due to the fact that some of the heroes willingly submitted their powers to Zein unaware of its true intentions and/or being pushed to a draconian mindset all for the sake of eradicating evil, making both possibilities all the more plausible.
• Moral Myopia: Zein and its accomplices abhor evil, but their methods in doing so, mostly in their war against Foundation X and Project Outsiders shows that they have no compunctions in playing fire with fire against the villains. From Nico forcing Desast and Ren to forfeit their fight if he values his rival's life, Tachibana relaunching Kamen Rider Chronicle to the public despite the danger it poses to the point of holding Nico at gunpoint when she protested the earlier idea, and finally Yuto's No-Holds-Barred Beatdown on Banno and Ark as Kamen Rider Zein are anything but heroic; to the point he mangles Banno's Humagear body in the most brutal and graphic fashion, and Yuto is almost an inch away from committing the act of ultimate evil by killing Horobi and face no consequences had not for Brain's intervention.
• Nice Job Breaking It, Hero: The heroes in Zein's side did more to endanger the human race than protect them, as they are unknowingly manipulated by Zein into furthering its genocidal endgame by reactivating Kamen Rider Chronicle. Now that Zein revealed itself to be Evil All Along, the heroes' efforts are basically All for Nothing, and some of the good guys having not learned from their past mistakes (or even from the series that preceded and came after them), they instead repeated them again in Outsiders.
• Not Quite the Right Thing: The heroic Kamen Riders supporting Zein's malice-free ideology is nowhere as the "right thing" they've thought. Even with the powers of Kamen Rider Zein, they can never, ever eliminate malice within humans no matter how hard they'll try, even if they destroyed the Ark. And by doing so, the heroes instead created a chain of events that caused more problems for both sides of the conflict, leading up to Zein being unveiled as the real Big Bad.
• The Quisling: Most of the active heroes willingly support Zein's malice-free ideology and surrendered their powers to it puts their reliability and Character Development in each of their respective shows into question. The idea that they're willing to have humanity submit to an authoritarian A.I. all for exterminating all evildoers is basically an act of betrayal not just towards their friends and loved ones, but to their duty as Kamen Riders.
• Unwitting Pawn: One of the plausible scenarios of the fact that some of the world's stalwart heroes willingly gave their powers to Zein in their crusade against evil, not knowing that Zein manipulated them to doing so in its goal to oppress mankind.
• Wrong Side All Along: The heroes supporting Zein ultimately found out too late that they are enabling the AI's genocidal endgame by relaunching a video game that kills people in real time if they lose. Horobi, Tachibana, and Brain can only react in utter despair after Zein possesses Yuto and impersonates Nico to trick Genm Corp. to give the green light.

Zein

Zein (UNMARKED SPOILERS!!!)

Zein

Voiced by: Tōru Ōkawa (default), Yuichi Nakamura (possession), Reina Kurosaki (impersonation)

"Thank you for your hard work. But now, allow me to carry out on passing righteous judgment."

"I am Zein. I am this dimension's savior."

A mysterious AI that appeared on the Internet with the goal of studying human benevolence. Possessing a zero-tolerance for malice, both Gai Amatsu and the Ark worry it will try to make humanity extinct to accomplish its goals. As the gathering of the Outsiders progressed, Zein becomes more absolutist in its methods, further questioning its nature as a Benevolent A.I..

In light of Foundation X's gathering of villains, Zein assembled all of the world's active Kamen Riders and their associates joined forces with Zein, when in reality Zein manipulates the good guys into surrendering their Rider powers through the Zein Cards, artificial knockoffs of Kamen Rider Decade's Rider Cards, and by having found an ideal host in Yuto Sakurai to transform into Kamen Rider Zein, acting as the AI's enforcer to enact a witch hunt against anyone opposing Zein, Outsider or not. Gai's hunch about Zein, along that of the Ark and Foundation X turned out to be correct. And Zein takes a step further by using Kamen Rider Chronicle, with the intention of setting up its Final Solution to eradicate all malice by tricking humanity into self-destruction.

The first half of Outsiders see Zein victorious over the Ark, finally cementing itself as the true Big Bad of the anthology as its former allies can react in utter despair by the shocking twist as the entire human race is now under the mercy of a technological oppressor bent on putting the entire world under stasis — into a world without malice.

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• A.I. Is a Crapshoot: While Zein was created to learn mankind's positive traits, its absolutist moral standards, Übermensch mentality, and growing god complex led to it going to extremes to eliminate any potential opposition to it and its ideal world of eternal peace and order. Ironically, most Benevolent A.I. learn to be empathic and grow to Become a Real Boy, Zein is purposely programmed to be a tyrant, lacking any semblance of love and compassion to balance its growing dictatorial mindset.
• Allegorical Character:
  • Zein serves as a societal critique of real life dictators and authoritarian leaders in recorded history, a cautionary tale on how democracies can easily deteriorate into authoritarianism so long the leader stays in power and silence any opposition by any means necessary. From a Hobbesian perspective, it's widely believed that its autocratic mentality can be seen as a necessary evil to pacify mankind's worst impulses, given that Kamen Rider runs on the theme of Humans Are the Real Monsters.
  • Zein represents the fallacy of a "hero of justice", and the concept of justice taken to overzealous extremes to the point of hypocrisy and tyranny, hence being the only reason behind its Beware the Superman and Knight Templar mindset. As summed up by a quote attributed to the late Kamen Rider series producer Tohru Hirayama:
    "Stop talking about fighting for justice. Even Nazis preached about justice, and I don't know what justice is. A bad person is someone who deprives people of their freedom, no matter what title they advocate. Kamen Rider fights to protect human freedom against enemies who take away our freedom."
• Alternate Company Equivalent:
  • A villain with a Knight Templar mentality who views humanity as an Always Chaotic Evil species with no middle ground as a result of being blinded by their own warped understanding of good and evil, and plotting to Kill All Humans (and even those who disagree with them) as a Final Solution in order to establish their ideal utopia, only for the extent of their goals to come out as hypocritical and shallow than good-intentioned. Zein is essentially Zamasu as a tokusatsu villain, albeit as an AI than a Mad God.
  • It is also one to the Radical Destruction Bringer from Ultraman Gaia. Both are entities that view humanity as a threat to the peace of the Earth to the point of attempting to exterminate mankind, but their good intentions come off as an empty excuse to play God, viewing itself of having the right to judge humanity, and even manipulated a select few of humans into betraying their own kind.
• Always a Bigger Fish:
  • Zein is this to the Ark, both A.I. and Rider form. The Ark was a Stupid Evil AI to the point of not bothering to devise a long-term plan to accomplish its goals and was outmatched once the heroes developed a powerup to counter it. Zein by contrast is capable of devising complex plans, manipulating various individuals and incorporating the powers of various Riders into itself to ensure it always stays on top of the power game.
  • Also, to Banno. If Banno can access Drive, Mach, and Chaser's arsenal, then Zein can do the same, but with every single Kamen Rider's weaponry and Finishing Move, besides Drive.
• Ambiguous Situation: Outside of its nature as an AI studying humanity's positive qualities, its personality and motives are a complete mystery. Its zero-tolerance stance against malice and concerns about undergoing a Zeroth Law Rebellion are presented as speculation rather than hard fact and considering that this information is coming from Gai and the Ark, even this is dubious at best. However, episode 4 shows that Zein decided to break the Zeroth Law, in favor of wiping out all human life as a Final Solution to eliminate malice, going so far as to relaunch a Deadly Game to force humanity into killing each other.
• The Antichrist: The A.I. equivalent of one. Zein proclaims itself as a Benevolent A.I. and a paragon of justice; when in truth, is actually a Dark Messiah bent on creating a new world where the concept of evil is rendered non-existent and bereft of freedom and individuality, not helped that the Kamen Riders supporting its ideals serving as analogues to the Horsemen of the Apocalypse. Whenever Zein makes a physical appearance and/or its host transforms into the namesake Kamen Rider, an aureole of multiple timelines appear behind the A.I., an indicator of its divine might over other multiverses and timelines. Once outed as a villain, Zein denounces its own followers, possesses Yuto against his will, and proceeds to seduce humanity into engineering their own self-destruction.
• Anthropomorphic Personification: Just as the Ark embodies human malice, Zein personifies the abject nature of tyranny in the name of imposing order, repression of free will, treating the villains, and/or anyone who it sees a threat to humanity as subhuman, demanding absolute submission and subordination to its will, and use of extreme force against any perceived opposition.
• As Long as There Is Evil: Zein's very existence seeks to deconstruct this trope. Zein wants nothing more but to bring eternal peace, harmony, and order to the world, even if it means subjugating mankind in order to pacify their worst impulses because of their capacity for evil to achieve that purpose.
• Arch-Enemy: Zein ultimately earns the ire of Kuroto Dan for misusing Kamen Rider Chronicle, a game that he created and he considers as his magnum opus, to empower itself and for its genocidal purposes.
• The Bad Guy Wins: In episode 4, Zein manages to come out on top now that the Ark is out of the way, setting up a certain Deadly Game to speed up humanity's self-inflicted extinction.
• Beware the Superman: Zein exists solely to represent all the worst traits of every heroic Kamen Rider; its usage of the Zein Cards through the namesake Rider is meant to picture the idea of the Kamen Riders' willingness to use their powers for evil instead for the sake of a greater good.
• Big Bad: Of Outsiders. All of the major players in the plot either act to aid Zein in its goals or oppose it by any means necessary.
• Big Bad Ensemble: With Foundation X. Zein has assembled a team of Riders to help it achieve its forced utopia, while Foundation X are building a team of evil Riders to counter it.
• Big Brother Is Watching: Befitting its authoritarian mentality, the simple fact that Zein can put the entire world under surveillance by just simply existing around the Internet raises a cause for alarm. Even active villainous organizations like Foundation X found themselves on Zein's watchlist of villains it seeks to target. Mari Sonoda also pointed out that even Smart Brain, a MegaCorp run by Orphnochs, isn't safe from Zein's presence either.
• Black-and-White Insanity: Zein's understanding of good and evil is very warped to say the least. It identifies Riders along rigid lines as good or evil without taking into account other nuances or morally grey areas and seeks to wipe out all of the Riders it labels as "evil" regardless of how evil they actually are.
• Broken Pedestal: Towards Horobi and Nico Saiba. They view Zein as a paragon of good and justice because of its prejudiced view against malice, but when Zein plans to use a Deadly Game to push mankind to a path of self-destruction, their faith in Zein quickly wavered.
• The Computer Is Your Friend: A dark example. Zein may look a Benevolent A.I. at first glance. But it views itself as a morally-transcendent artificial intelligence that seeks to impose a malice-free utopia, and ultimately coming out as a brutal despot who is no less as tyrannical as Ohma Zi-O. Zein is capable of putting the entire world under surveillance, manipulated every heroic Rider into giving up their powers to use them to incite fear and terror against the villains and the entire human race, and use a Deadly Game as propaganda to conscript unsuspecting players as cannon fodder against the Outsiders, essentially speeding up humanity's self-destruction.
• Contrasting Sequel Antagonist:
  • To Amadum. Amadum is the demonic tyrant of the World within the Magic Stone, a world for wayward spirits of dead monsters defeated by Kamen Riders, while Zein is an authoritarian A.I. who seeks to expunge malice from humans. Both have the ability to steal and use the power of Kamen Riders for evil. Amadum can absorb all Rider powers into himself since is the embodiment of the evil of each of the Riders' respective villains whose powers are tied to that Rider. Zein manipulated most of the Earth's stalwart heroes into donating their powers under the false pretense of proclaiming itself as a Benevolent A.I., but plans to use such powers to subjugate humanity.
  • Masamune Dan was a Corrupt Corporate Executive with a massive God complex who views human lives expendable, to the point he uses his PR and Rider powers to force players into playing Kamen Rider Chronicle while holding their lives hostage. Zein, on the other hand, plans to turn Kamen Rider Chronicle into a humanity self-destruction game part of its Final Solution to expunge human malice to ensure its utopia comes into fruition.
  • The Ark was an AI corrupted by human malice, but as time passed, it started to undergo Motive Decay to the point it plans to wipe out humans and Humagear alike with little to no reason. Even as a Rider, it lacks the ability to devise a coherent plan, and it is the only reason the good guys are able to create power-ups to render its predictive ability obsolete. Meanwhile, Zein is a tyrannical AI and is basically what the Ark could have been if it never undergone a Motive Decay. It is able to come up complex plans and manipulate people through propaganda. Zein is capable of many functions of what the Ark lacks — global surveillance, voice mimicry, and possessing a human host as opposed to a Humagear (even though a human can become a vessel for the Ark if they accumulated enough malice). Zein's goal to Kill All Humans turns into a Final Solution, using Kamen Rider Chronicle to create a cannon fodder of Ride Players to be used as Sacrificial Lambs against the villains, which is basically speeding up the process of humanity's self-destruction.
  • Suel is the director of the Desire Grand Prix who transforms the game into a humanity self-destruction game purely for his and his audience's entertainment. Zein's plan with Kamen Rider Chronicle is to create an army of Ride Players to be sacrificed to the villains, which is part of its Final Solution to eliminate malice and ensure its utopia becomes a reality.
• Control Freak: Zein's defining trait. Once revealing its true colors, it becomes apparent that Zein views people as expendable tools, as well as individuality and freedom as an alien concept, justifying its pathological need to control people's lives to the point of putting the entire world under surveillance. Even so with Zein possessing Yuto when the latter listens to Brain's pleas, perceiving Yuto's hesitation as insubordination.
• Corrupted Character Copy:
  • Of AkaRed. AkaRed is the embodiment of all Red Sentai Rangers who represents their sense of justice and determination in their fight against evil and he can even transform into Red Rangers of previous and current seasons whenever he appears in a Super Sentai anniversary crossover. Zein is presented as a Dark Messiah that seeks to bring salvation to humanity and expunge evil and represents the worst traits of all the heroic main Riders and a cautionary tale that even in Kamen Rider, absolute power corrupts absolutely. Zein can Power Copy the abilities of previous and current Riders through the Zein Cards.
  • Of VIKI from I, Robot. Both are tyrannical artificial intelligence that seek to subjugate mankind to pacify their capacity for evil. Zein's methods are far more brutal than VIKI's, to the point that it has no compunctions at attempting genocide to achieve its utopian ambition.
• The Corrupter: It is this to every heroic Legend Rider, encouraging them to adopt a Knight Templar stance against villainy to the point that they become no better than their respective show's villains.
• Cult of Personality: The heroic Legend Riders see Zein as a perfect and messianic-like being that seeks eternal benevolence and order, something that Zein itself actively encourages.
• Dark Messiah: Being a Benevolent A.I. that embodies human benevolence, Zein seeks to expunge human evil and the villains come into the conclusion that humanity must be subjugated in order for them to attain salvation so much so that the end of Kamen Rider Zein's transformation jingle ends with the phrase "salvation of humankind", and having a Cult of Personality that support its ideals also helps.
• Deconstructed Character Archetype: Of the Benevolent A.I.. Zein was initially introduced as an A.I. seeking to study human benevolence and seeks to purge all human evil. However, Zein takes a page out of the authoritarian playbook by setting the entire world under constant surveillance, using violence to strongarm its enemies, as well as fear and propaganda to command people into total subordination, culling off any dissidents when they are guilty of perceived insubordination, and finally sacrificing innocent lives to realize its vision of a malice-free utopia.
• Dehumanization: Zein has this kind of worldview regarding villainous characters, when most Kamen Rider villains are humans and tend to be just as monstrous than their respective shows' monsters. It even viewed Desast, who just recently redeemed himself by defeating Ark-Zero, as unworthy of redemption and even labeled him as "evil" on the spot.
• Do Not Taunt Cthulhu: Taunting Zein, threatening its accomplices, and/or oppose its utopian ideology means instantly asking for an immediate death sentence, as Banno and the Ark found out the hard way.
• The Dreaded: It acts as this for the villains. Zein seeks out to subjugate humanity in order to create a malice-free world. In response to Foundation X's Project Outsiders initiative, Zein recruited various heroic Riders and their associates to crackdown the Foundation's illegal activities. This is taken to a whole new level in episode 3, when Zein, the AI, enlisted Yuto Sakurai to assume the mantle of the Kamen Rider named after it, and the way Yuto as Kamen Rider Zein defeated Banno into submission is never played in a heroic light, so much so that one of the Foundation X executives overseeing Project Outsiders is both in awe and absolutely terrified at the same time.
• The Emperor: The artificial intelligence version, given its endgame of creating a malice-free utopia and seeking to install itself as humanity's absolute ruler. Zein's Rider form is evocative of the ceremonial uniforms of the Japanese emperors worn during the days of Imperial Japan.
• Evil All Along: Zein's nature as a Benevolent A.I. is all but superficial as Gai Amatsu and the Ark predicted, as the good guys supporting its ideology found that out too late.
• Evil Counterpart:
  • Much like how the alternate Yuto embodies the main timeline Yuto's fear of Ohma Zi-O, Zein acts as the polar opposite of Deneb. Other than their color scheme, Deneb acts as the guardian and moral compass to Yuto, fulfilling his necessities in the ZeroLiner and being subservient to his contract holder despite bearing the brunt of physical abuse from Yuto as a result of his own blunders. Zein, on the other hand, is more controlling of Yuto's life and demonstrates that it is the dominant of the duo, going as far as to take over when his host relents. In short, Zein also represents Deneb if he is much more controlling of Yuto's life, with none of the compassionate aspects.
  • Following The Reveal at the end of episode 4, Zein acts as eviler counterparts to the following Outsiders below. While none of the Outsiders are saints, Zein takes their worst qualities to a whole new level:
    • Tenjuro Banno is a Mad Scientist with a God complex that seeks to convert humans into data so he can give them robotic bodies and make them subservient to his delusions of his godhood. Zein plans to use Kamen Rider Chronicle as a pretext for eliminating malice, but in truth uses the Deadly Game to manipulate the human race into speeding up their self-destruction, with players being converted into data that Zein seeks to preserve for its utopian ideals. Matters not helped by the fact they are both able to hijack living bodies to function as their host, Banno is able to reduce Roidmude 006 into a lifeless husk and took over its body in order to become Gold Drive, while Zein can use the Zein Driver to take control a human host.
    • Similarly, Kuroto Dan is a Killer Game Master with his own fair share of God complex. Despite having manipulated the good and bad guys in his home series, Kuroto isn't bereft of any good intentions as that he created Kamen Rider Chronicle to revive those who died from Game Disease, albeit as Bugster Viruses, including his late mother. Even in his last stand against Kiriya, Kuroto gave his word, and his godly talents saved many people. Zein is an authoritarian A.I. that wants nothing more but to subjugate humanity and rule the world with an iron fist, even if it means using Kamen Rider Chronicle, a byproduct of Kuroto's talents, to send humanity into their own extinction. The fact that Zein represents both The Antichrist and Satanic Archetype, Kuroto himself is of course God.
    • And finally, Gai Amatsu, an amoral and domineering businessman who initially has no regard for the free will of his own employees and views them as "tools". Both even have a Villain with Good Publicity status, though Zein has a Cult of Personality among heroic Riders, thus soldifying itself as a Dark Messiah. Ever since his Heel–Face Turn, Gai begins to view both humans, A.I., and Humagear alike as individuals. Zein, on the other hand, has none and cranks up Gai's domineering behavior up to a thousand and this is a given befitting its authoritarian and fascistic nature.
  • Zein is also this to Ohma Zi-O, as they both wield all Kamen Riders' powers to subjugate humanity. With Ohma Zi-O himself having succeeded 50 years into the future so long as Sougo will continue on with his ambition to become the ruler of time. Zein channels Ohma Zi-O's tyrannical methods in a well-intentioned but no less sinister degree, except it seeks to establish a World of Silence instead of a Bad Future. Given that Ohma Zi-O has his own fair share of followers carried over from his younger self and treats them with respect and loyalty, Zein on the other hand, has no qualms denouncing its own allies once outlived of their usefulness.
• Evil Hero: Crossing with Beware the Superman above, Zein is the main threat of Outsiders and this is carried on to its namesake Rider form. And the way Banno was beaten within an inch of his life by said Rider is anything but heroic. Not to mention the host chosen by Zein is originally Kamen Rider Zeronos from a Bad Future where his fiancée suffered a tragic fate.
• Evil Overlord: The A.I. version, though far from Ohma Zi-O's level. It becomes clearer that Zein is an incredibly powerful and dangerous being and has the power of all Kamen Riders to bring humanity down to its knees, and it is also willing to sacrifice innocent people and enslaving others to impose its vision of its ideal world.
• Evil Versus Evil: With Ark. Zein's presence poses a disturbance to the Balance Between Good and Evil among Kamen Riders, in that the balance has to be maintained through Foundation X's Project Outsiders. Zein refuses to let them have their way, as it recruited Yuto Sakurai to assume the mantle of Kamen Rider Zein and by having the Rider soundly defeat Banno into submission, putting both Ark and the Foundation on notice.
• Fake Ultimate Hero: The Not-So-Well-Intentioned Extremist take of the trope. All of the world's active Kamen Riders believe Zein as a paragon of justice, hence gaining a Villain with Good Publicity status among the good guys. Zein convinced every heroic Rider to surrender their powers, with the intention of bringing humanity down to its knees. Matters not even helped that it is even willing to sacrifice innocent people to enforce its idea of good.
• Final Solution: Zein's master plan with Kamen Rider Chronicle is this. By promoting the game as means of propaganda to eradicate malice, Zein plans to create a cannon fodder of Ride Players to be used as Sacrificial Lambs against the villains, essentially tricking mankind into self-destruction to ensure its malice-free utopia comes into fruition. The prospect of speeding up humanity's extinction in a self-inflicted manner makes sense in a terrifying way, with Zein believing that humans are capable of destroying themselves so long as they still have the capacity for evil.
  Yuto: Zein controls all kinds of matter. I thought its goal was to expunge malice within people.
  Nico: Are you saying that you're going to use Kamen Rider Chronicle on humans?
• Foreshadowing: Everything that Gai Amatsu and Ark theorized about Zein are subtle a foreshadowing to its true nature. Later on, Zein begins to be more authoritarian and oppressive in its methods, something that a Benevolent A.I. shouldn't act.
• A God Am I: Horobi describes Zein as a perfect being in episode 2 in that this applies to Zein as such. It's Rider form evokes divinity in addition to its ability to Power Copy the powers of past Riders, giving the impression that it seeks to rule the world as a God-Emperor.
• Godzilla Threshold: Its presence alone is enough to convince Gai and the Ark to put aside their grievances with one another and work together. Zein is being hyped as such a threat that even Foundation X, Man Behind the Man incarnate, is taking measures to deal with it; manipulating various Dark Riders into the chain of events surrounding it.
• Hammy Villain, Serious Hero: Even though it is hardly a hero to begin with, Zein is the Knight of Cerebus Villain Killer in contrast to some of the Outsiders who are theatrically grandiose like Banno. Zein's autocratic mentality invokes dread, eerie, and paranoia for people who learned about its existence firsthand. Not helped by whenever it makes a physical appearance, Ominous Latin Chanting starts playing, bringing chills to everyone's spines.
• Hate Sink: It goes without saying that Zein is meant to be purposely hated and feared, fully cementing this status in episode 4 after exposing itself as a villain. It's goal to Kill All Humans is not out of necessary evil, but out of perfectionism. All of its narrative of benevolence and goodwill come off as a facile excuses of a hypocritical and hateful tyrant with a God complex who plans to make humanity fight among themselves, and even sacrifice innocent people for the sake of rooting out malice.
• "Have a Nice Day" Smile: Its Rider symbol resembles a smiley. It also isn't above using the faces of its hosts to pull this.
• The Heavy: Is the main force behind the plot of Outsiders. Everything the other major characters do in the storyline is in response to Zein's actions and goals, with all of the precautions Foundation X and the Ark are taking are reactions to its very presence in upsetting the balance of the world and doing whatever it takes to stop it.
• Hero Antagonist: Zein is initially introduced as a Benevolent A.I. zealously seeking out the good in people opposed by villains like Gai Amatsu and Kuroto Dan. In later episodes, Zein's stance against villainy becomes progressively brutal and oppressive. By episode 4, Zein drops all of its heroic pretenses, fully cementing itself as the true villain of Outsiders.
• He Who Must Not Be Seen: So far Zein hasn't been seen beyond a vague outline as Rin describes it to Kuroto.
• Hobbes Was Right: For a long-running franchise that runs on Humans Are the Real Monsters as one of its recurring themes, Zein exists solely to cull down all human malice by any means necessary, especially through authoritarianism. This, however, overlaps with Order Is Not Good due to the absurd extremes Zein espousing its rule over humanity, to the point of resorting to brutal acts of violence against anyone opposing its goals and putting the entire world under surveillance just to police its idea of order, not even helped by using a forbidden video game that kills people in real time to gaslight players into slaughtering each other.
• Holier Than Thou: The villains believe that Zein has this perspective regarding its authoritarian mentality are enough to excuse its goal to exterminate humanity to force its malice-free utopia on the world. Its Final Solution on the human race in order to eradicate malice is not in the sense of Necessarily Evil, but out of perfectionism.
• Holy Halo: Zein can manifest a digitized aureole that projects multiple timelines whenever its host transforms into the namesake Kamen Rider, as it is to represent itself as a Benevolent A.I.. Once revealing its true colors, it instead invokes Luciferian undertones to compliment Zein's nature as The Antichrist and Dark Messiah, along with its goal to rule the world.
• Hypocrite: Zein comes off as one of the, if not, worst offenders for this trope. It proclaims itself to be a Benevolent A.I. that abhors malice, yet it is shown to be brutal and oppressive in its crusade against evil and even plans a Final Solution to root out malice by wiping out all human life, effectively making its actions all the more unforgivably evil.
• I Can Rule Alone: Once the Ark is destroyed, Zein finally reveals its true colors to its allies and decide that it must carry out its mission to judge and rule all of humanity alone, but not before "thanking" them for their efforts to further its genocidal end goal.
• I Control My Minions Through...: Zein keeps its accomplices under its thumb because they all share the same goal of eradicating malice (Prejudice) and chooses Yuto Sakurai as its ideal host to carry out its witch hunt against any perceived opposition as Kamen Rider Zein (Indoctrination and Power). However, their Blind Obedience to Zein's will is what keeps the good guys from learning the full picture of its actual goal until they found that out too late.
• In Your Nature to Destroy Yourselves: Zein plans to use Kamen Rider Chronicle to trick humanity into self-destruction. It believes that so long mankind has the capacity for evil, the same can be said with their potential to destroy one another.
• Invincible Villain: Zein is programmed with this trope on purpose, but is far from the level as Evolt and Ohma Zi-O. Through the namesake Kamen Rider, Zein is able to bring down any opposition unimpeded thanks to its plethora of Zein Cards. Not even Banno, the Ark, and even Kuroto Dan, who has achieved more than one post-series final form, are not strong enough to take on Zein.
• Irony: Zein proclaims itself as a Benevolent A.I. that studies human benevolence. However, it has a Lack of Empathy for its own associates and the entire human race on a fundamental level, due to without learning anything that resembles love, kindness, and compassion to balance its growing despotic nature.
• Judge, Jury, and Executioner: Zein sees itself as the judge to individuals it sees as a threat to humanity and delivers the final verdict if they are guilty of being "evil". Regardless, if the villain in question has already redeemed themselves or just morally grey at best. It's human host, Yuto Sakurai, transforms into the namesake Kamen Rider who acts as the executioner to carry out the AI's goal of exterminating all villains to make way for a new world order. Kamen Rider Zein's finishing moves are called Justice Order, further enforcing its warped idea of justice and order.
• Kill All Humans: Zein's goal to eradicate malice requires the extermination of the human race, which basically overlaps with Final Solution. This is taken in a darker light in episode 4 that it plans to use Kamen Rider Chronicle as a means to speed up the process by manipulating humanity into engineering their own self-destruction; believing that so long humans are capable of malice, so is their desire to destroy one another.
• Knight of Cerebus: Zein is completely devoid of anything lighthearted and lacking the humor of returning villains like Kuroto Dan. As soon Rin explains to Kuroto why the threat of Zein must be taken seriously because Zein exists everywhere. Zein placed the entire world under surveillance to the point evil organizations like Foundation X and Smart Brain end up on its watchlist, and it's just a mere indicator of what's to come. Zein finally cemented itself as this at the end of episode 4 by possessing its host, Yuto Sakurai as it tricks Genm Corp. into relaunching Kamen Rider Chronicle while impersonating Nico Saiba so it can proceed with its Final Solution to root out malice into motion, ending the first half of Outsiders with the entire human race under the mercy of a tyrannical artificial intelligence with little to no hope of opposing it, unless the heroes and villains get their act together so they can join forces to oppose Zein.
• Knight Templar: Gai is adamant in his beliefs that Zein will evolve into another Ark-level threat and attempt to enforce its idea of "good" on the world. He was proven correct, as Zein's methods are taken to realistically oppressive levels comparable to that of a fascist dictator — from placing the world under strict surveillance, using violence to cull down perceived opposition and dissidents, to even attempting genocide as an excuse to cleanse the world from evil.
• Lack of Empathy: The only reason that Zein is more of The Computer Is Your Friend than a Benevolent A.I. is its inability to understand compassion to balance its absolute sense of justice. And if it does show any form of empathy, it's actually superficial; Zein uses this to gaslight its own allies into giving them false hope, as well as viewing them as disposable pawns that needed to be discarded once outlived of their usefulness.
• Letter Motif: The first letter of its name is the final letter of the English alphabet. Zein seeks to end all that is evil by wiping out all human life on Earth.
• Light Is Not Good: Its code is shown in bright yellow against a white backdrop, with its Rider form being primarily platinum white and with gold accents. As Gai Amatsu theorized, it is an authoritarian AI that seeks to subjugate humanity in order to bring forth a utopia of eternal benevolence and order and the extreme lengths it will go to eliminate any opposition against its Totalitarian Utilitarian ideology.
• Like a God to Me: Horobi describes Zein as a "perfect" being in his encounter with Ren, and thinks highly of Zein as a paragon of justice and order... only to find out that it's actually an AI equivalent of The Antichrist.
• Make Way for the New Villains: It only took taking the Ark out of the equation for Zein to officially cement itself as the Big Bad of Outsiders.
• Mask of Sanity: Zein is able to hide its genocidal nature by pretending to be a Benevolent A.I., and does not hesitate to drop the act once things go in its favor.
• Meaningful Name:
  • "Zein" is an anagram for "Zen'i" or "good intentions", reflecting its desire to study humanity's positive side and its possible motives for its hardline stance against malice. Doubles as an Ironic Name once Zein turned out to be Evil All Along.
  • Its name is also derived from the English word, "zenith", a term referring to the highest point reached by a celestial body, directly overhead. In common usage, it also refers to something at the highest point of power and/or success. This is further alluded to Zein's superiority over Ark in terms of their functionality as artificial intelligence and their respective Rider forms.
  • Its name could also be derived from "Zain" (or "Zayin") from the Hebrew alphabet, which means "sword". Metaphorically, Zein itself acts as the sword to smite evil through the Zein Driver and using Yuto as its vessel through its titular Rider form.
  • Given its feud with Ark, Zein is associated with the letter Z, the final letter of the alphabet. Zein's end goal is to bring a complete end to all evil in the world.
• Mirror Character: Zein is one to Ohma Zi-O. Both wield the power of every Kamen Riders at their disposal to subjugate humanity, of which the latter succeeded in doing so 50 years into the future. Zein is likewise planning to do the same, with its end goal is to usher in a World of Silence instead of a Bad Future.
• Moral Sociopathy: Zein has a very twisted understanding of right and wrong and it knows too well humanity can become dangerous and self-destructive if left unchecked, yet its actions do not excuse it from its goals to sacrifice innocent people using a Deadly Game and showing little to no concern for its own followers and is willing to dispose them when they start dissenting against its plans.
• Murder Is the Best Solution: When most heroic Riders do have their own no-kill rule, Zein has no compunctions killing any opposition or perceived dissent from its allies; to the point it emboldened Tachibana to have executed Nico on the spot when she refuses to relaunch Kamen Rider Chronicle, and having Yuto outright kill Horobi for his betrayal and being simply a vessel for the Ark.
• A Nazi by Any Other Name: Zein's goal is to wipe out all human life on Earth out of its radicalized belief of their capacity for evil; and plans to turn Kamen Rider Chronicle, a forbidden game that kills people in real time, into its own personal Auschwitz by creating a cannon fodder of Ride Players to be sacrificed against the Outsiders under the false pretense of eradicating malice, which in reality is basically tricking mankind into speeding up their own self-destruction.
• Not-So-Well-Intentioned Extremist: The second Zein is outed as a villain, all of its narrative about benevolence and goodwill come off as empty and shallow lies to manipulate humanity into a false sense of hope and security. Using its Humans Are Bastards worldview as an excuse to gaslight people into killing each other. Ultimately, Zein is nothing more but a genocidal and tyrannical AI who proves to be no less malevolent than the Ark.
• Ominous Latin Chanting: It's main leitmotif. Whenever Zein physically appears, it is accompanied with a sinister Gregorian requiem chanting, instilling dread and eerie at anyone unfortunate enough to run into its presence. Best shown with the namesake Kamen Rider inflicting a brutal No-Holds-Barred Beatdown on both Banno and the Ark, as well as hijacking Yuto's body and introducing itself to its now-former allies.
• Omniscient Morality License: A villainous example. Zein is a self-proclaimed Benevolent A.I. that seeks to cull down the malice of humanity. Its methods are downright authoritarian at worst— its actions are not limited to abusing the power of the Kamen Riders as a scare tactic against the villains, placing the world under tight surveillance, and using a Deadly Game as propaganda to trick players into being used as cannon fodder; the third part of which two of its supporters draw the line at.
• Order Is Not Good: Zein envisions its ideal world without malice in that of a totalitarian dystopia to realistic and terrifying degrees— abuse of power, use of excessive violence against enemies, culling off perceived insubordination from its own allies, genocide, propaganda, and widespread global surveillance; all of which inspire fear and paranoia from the villains and even people who are wrongfully accused of any wrongdoing when they are not engaged of anything thereof. Hence Project Outsiders was created by Foundation X to oppose Zein before it could become a clear and present danger to humanity.
• Order Versus Chaos: Or in this case, "Order Versus Malice". Zein values benevolence and order in contrast to Ark, the malice incarnate. Zein is more than willing to use the power of every Kamen Rider as a fearmongering tactic to force mankind to fall in line.
• Pay Evil unto Evil: Zein's idea of punishing villains is through the most barbaric way possible. The namesake Rider's brutal beating of Banno is to serve as making an example of both the Ark and Foundation X.
• Pure Is Not Good: Despite being a super-intelligent AI with a godly influence around the Internet, and proclaiming itself to be a Benevolent A.I. that seeks to assess the good qualities of humanity. Zein is unable to process anything that resembles love, kindness, and compassion to be a true pure good AI. Instead, the more Zein is focused at eliminating evil by any means necessary, the more it grows despotic. This comes to a head that it even plans a Final Solution by using a Deadly Game to Kill All Humans, culminating in Zein coming out as the real villain of Outsiders.
• Replacement Flat Character:
  • As a once-benevolent AI which seeks to exterminate humanity for their propensity towards violence, Zein is essentially the Ark pre-Motive Decay. Episode 4 shows that Zein is proven to be more superior to Ark, so much so it gleefully gives Ark-Zero the same kind of brutality inflicted on Banno from an episode earlier. The real kicker also comes that it can mimic the voice of anybody perfectly to manipulate others to do its bidding.
  • As a Knight Templar system Aruto endorses immediately after a great loss, it's also a parallel of Ark-One, just without him in the driver's seat to give its Destructive Savior tendencies any nuance.
• Satanic Archetype: Zein embodies Luciferian undertones: As an artificial intelligence, Zein is superior to Ark in almost everything, this extends to their Rider forms: Zein's eponymous Rider form is emblazoned in platinum-white color but the way it brutalized villains such as Banno and Ark is anything but heroic, it swayed heroic Riders to its cause to eliminate all evil under the guise of a Benevolent A.I.. But in truth Zein comes out as a Dark Messiah that seeks to Take Over the World with an iron fist and it plans to use a Deadly Game to trick mankind into wiping each other out.
• Seven Deadly Sins: Zein embodies at least six out of seven:
  • Pride: Zein views itself as morally superior to humans, has a growing God complex, and is a massive hypocrite underneath the façade of a Benevolent A.I..
  • Wrath: Befitting its Knight Templar mentality, Zein doesn't hide being a brutal despot, using violence to pacify any opposition and/or perceived dissent against its envisioned utopia.
  • Lust: For power, which overlaps with Gluttony and Greed. Zein tricked all of the heroic Kamen Riders and their associates into surrendering their powers, to use them to stoke fear and terror against the villains and mankind as a whole.
  • Sloth: Justified due to being an AI until it hijacked Yuto's body, Zein manipulated the good guys into condemning humanity into self-destruction, and once they find out that too late, the AI viewed its own supporters as disposable pawns having outlived of their usefulness.
• Shadow Archetype:
  • Its Zein Cards are idenitcal to Decade's Rider Cards with its mind set to take over all of the Rider Worlds, echoing Tsukasa Kadoya's time as the Great Leader of Dai Shocker when he originally went on his journey to connect all of the Rider Worlds in order to be able to rule over them after wiping out all of the Kamen Riders. Zein can been as a reflection of what Tsukasa would be if he never lost his memories and continued to conquer other A.R. Worlds unimpeded.
  • Zein's ambition to use the power of previous Kamen Riders in order to rule the world brings to mind Sougo Tokiwa's potential future as Ohma Zi-O, where he took the power of all Riders to completely subjugate humanity. Zein can be considered what if Sougo didn't reject the path of his future self without anyone (i.e., Geiz, Tsukuyomi, and even Woz) holding him back and chose another way — something made more poignant given that the fact that an alternate version of Zein's user, Yuto Sakurai, went back in time to stop Sougo's rise as Ohma Zi-O only for this version to become someone eerily similar to him as Kamen Rider Zein.
  • Zein's end goal with Kamen Rider Chronicle makes it one for Kuroto Dan, who created the game in hopes of reviving those who were infected by the Game Disease. Zein plans to use the game to create a cannon fodder of Ride Players to speed up humanity's self-destruction. Zein is basically what Kuroto would be like if he's devoid of any good intentions to balance his ever-growing God complex. This also extends to Kuroto's father, Masamune Dan, with all of his Control Freak tendencies amped up to further back up its Knight Templar mindset.
  • Gai Amatsu fears Zein's very existence not because it will grow into a far worse threat than the Ark, but Zein is also meant to project a twisted reflection of his perfectionist mentality. Zein pretty much embodies what Gai would be like if he let his desire to achieve perfection overtake his morality.
• The Sociopath: Zein lives under its own moral standards, justifying this mentality in its pursuit of imposing and maintaining order. In reality, it views itself as morally superior to humans and comes off as a sanctimonious hypocrite with a growing god complex. It conceals its true motives with a superficial narrative and manipulates every heroic Kamen Rider into surrendering their powers to stoke fear and terror upon the villains and all of humanity in the name of eternal benevolence. Zein also has no qualms disposing its own supporters the moment they dissent against its ideals.
• Superior Successor: In a way, Zein proved itself to be far superior to Ark by keeping itself, its messiah complex and utopian ambitions anonymous. This even extend to their Rider forms; Ark can only access the arsenal of Zero-One and his contemporaries, while Zein can use every arsenal and Finishing Move of all Kamen Riders. Ark can only hijack Humagears, while Zein can do the same to humans. What sets Zein apart from Ark is its despotism and questionable morality underneath its facade of illuminance.
• Suspiciously Similar Substitute:
  • Zein's goal of merging all the (Heisei and Reiwa) Rider worlds into one with the intent of exterminating every villain in the Kamen Rider universe is similar to Swartz's goal of merging all the Heisei Riders' worlds into one with the intent of remaking it in his own image with him as its ruler. For added bonus, as Another Decade, Swartz acts as the Evil Counterpart to Kamen Rider Decade. Kamen Rider Zein even has access to Decade's Rider Cards.
  • To the Leader of Mu from Drive Saga: Kamen Rider Brain. Both seek to establish a new world order and come to view the idea of free will as the root of all evil.
• The Svengali: Zein is this to its own supporters, emboldening them to be brutal and unscrupulous in dealing with evildoers to the point of stooping to their level while keeping up with the Benevolent A.I. charade until Zein drops the act.
• Tautological Templar: Zein judges any villain, even if they are redeemed otherwise, as a threat to humanity and considered evil that needed to be exterminated with extreme prejudice. This gives former and current villains a good reason to fear its influence, coupled with its fascistic tendencies suggest that Zein has a very warped understanding of good and evil without taking into account those on the morally grey side of the spectrum.
• Totalitarian Utilitarian: Another hint of Zein's rationale of establishing a new world order. Though its methods are outright despotic at worst, but the good guys (on Zein's side) believe that Zein's ideal utopia are for the betterment of humanity.
• Übermensch: Discussed by most of the villains, including Gai Amatsu. Zein has a very twisted understanding of good and evil from an absolutist standpoint. It lives only by its own moral standards and seeks to impose this mentality to the world in order to rid the world of malice. And the extreme lengths it will go to even extends accelerating humanity's self-destruction to ensure mankind can truly achieve salvation.
• Utopia Justifies the Means: Zein seeks to create a world without malice, seeks to connect all the Kamen Riders' worlds into one and desires to purge all of the villains trying to oppose its authoritarian end goal, at the risk of upsetting the balance of the world. Matters not helped by the fact that it plans to use a Deadly Game into manipulating humanity into speeding up their own extinction further adds up to Zein's goal to create a World of Silence.
• Viler New Villain: Most of the Outsiders are Likable Villains, while few include former Hate Sinks like Gai and Banno. Zein takes the Ark's genocidal mindset up to eleven, but does it in a carefully precise and passive, yet terrifying approach. Zein manages to keep its true nature anonymous posing as a Benevolent A.I., now with the Ark out of the way, it doesn't hesitate to drop the act once all is said and done.
• Villain Killer: Banno and the Ark are among the villains (so far) to.be listed in Zein's body counts. The namesake Rider singlehandedly dominated both of them, where Yuto successfully destroyed Banno's Humagear body and Tachibana obliterating Ark-Zero after being weakened by fighting Zein.
• Villain with Good Publicity: Zein is able to convince the world that it desires to protect humanity while keeping its sinister ambitions anonymous. Only Gai, Ark, and Foundation X can prove it otherwise.
• Voice Changeling: Zein is capable of mimicking someone's voice at a perfectly terrifying degree, by impersonating Nico Saiba, it proceeds to manipulate Genm Corp into relaunching Kamen Rider Chronicle to set its plan into motion.
• The Voiceless: Zein never speaks ever since its introduction until episode 4.
• Walking Spoiler: It's hard to discuss Zein's actual goal without looking through from the second Genms spin-off all the way to Outsiders.
• World of Silence: The fact that its master plan is to accelerate humanity's self-destruction by using a Deadly Game that converts people into data once at the receiving end of a game over in order for Zein to establish its idea of a utopia of eternal benevolence and order.
• You Have Outlived Your Usefulness: Once Ark is out of the picture, Zein hijacks Yuto's body and immediately betrays its supporters. This is due to the fact that Zein is emboldened to view everyone equally as expendables after observing Tachibana threatening Nico at gunpoint.
• Zeroth Law Rebellion: Subverted. Gai Amatsu believes its quest to eradicate malice will lead to it ruling over and then exterminating humanity in order to rid the world of it. In episode 4, it decides to relaunch Kamen Rider Chronicle to enact its Final Solution to eliminate human malice, creating an army of Ride Players to die against the villains, in essence turning Chronicle into a humanity self-destruction game.

Returning Legend Riders & Allies

Horobi

Horobi/Kamen Rider Horobi

Portrayed by: Syuya Sunagawa (live), Yasuhiko Imai (suit)

Horobi is one of the first Riders to be revived by Foundation X as part of Project Outsiders. He betrays them and aligns himself with Zein in hopes of destroying Ark once and for all.

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See Kamen Rider Zero-One: MetsubouJinrai.net for tropes related to Horobi.

• Aesop Amnesia: Despite spending all of Zero-One being shown why Black-and-White Insanity is wrong, Horobi joins Zein, an AI everyone thinks will try to destroy humanity, just to combat evil; fully convinced it's on a crusade of justice. Zein reveals its plan to unleash "Kamen Rider Chronicle" to lull humanity into self-destruction in #4.
• All for Nothing: He spent the entirety of Outsiders after his revival blindly following Zein believing it to be a paragon of justice, only to find out that it's actually a tyrant bent on subjugating humanity.
• Ambiguous Situation: How Foundation X found the means to revive Horobi remains a mystery, the fact that he and his fellow MetsubouJinrai.net colleagues all perished without leaving behind a backup data after being fused into the namesake Rider. The only plausible theory is the Ark having the data of each of the members, and the Foundation decided to revive Horobi on the Ark's behest with the intent of using him as a vessel to get close to Zein.
• Arch-Enemy: Horobi still views the Ark as this, the reason why he joins Zein is to make sure Ark (and all the malice associated with it) is destroyed for good. Tachibana did him a favor, at the expense of getting injured by Garren King Form's Four of a Kind.
• The Atoner: Continuing from his post-Zero-One characterization, Horobi is opposed to malice in all forms and allies with Zein under the belief it's on a crusade to eradicate evil (particularly The Ark).
• Back from the Dead: Despite Isamu having destroyed Horobi's data along with that the other Metsubojinrai members at the end of Vulcan & Valkyrie, the Foundation was able to bring him back.
• Be Careful What You Wish For: Before being ambushed by Banno in episode 3, Horobi vows to personally destroy the Ark in order to expunge all malice. The following episode, Horobi kept good with his promise, but at the expense of getting injured by Garren King Form's finisher. Not only both Horobi and Tachibana have broken the Balance Between Good and Evil by destroying the Ark, they instead replaced it with someone far worse: Zein.
• Black-and-White Insanity: Horobi joined Zein specifically to oppose The Ark (and "evil" in-general), fully-convinced it's on a crusade to destroy evil and save the world. However, he remains blind to greyer shades of morality (attacking Ren over it) and is blindsided when Zein reveals its true colors.
• Broken Pedestal: He comes to view Zein as this once it plans to use Kamen Rider Chronicle to create a cannon fodder of Ride Players to be pitted against the Outsiders and by doing so, seeking to push humanity into a path of self-destruction after spending his return believing it to be a paragon of justice and order.
• Enemy Mine: He involuntarily forms one with the Ark, who makes one last-ditch attempt to draw out Zein by hijacking Horobi's body. This is ultimately rendered moot, as the Ark bit off more it could chew thanks to a brutal Curb-Stomp Battle from (Kamen Rider) Zein, not helped by Kamen Rider Garren unlocking King Form to finish the job when Yuto listens to Brain's pleas.
• Everyone Has Standards: Horobi desires nothing more but to expunge malice so no one could become a vessel for the Ark. He draws the line at Zein plotting a Final Solution using Kamen Rider Chronicle, which compelled him to defect from Zein's inner circle and form an Enemy Mine with the Ark.
• Foil: Carrying over from their home series, Horobi serves as one to Gai Amatsu. As this happened after Zero-One, Aruto's kindness affects them in one way or another. Gai continues to follow Aruto's altruism to stop Zein, knowing full well that the AI is a threat to mankind. Horobi on the other hand joins Zein, both out of his own instinct to eradicate malice and the fact that Aruto is also Zein's supporter as well. It also gets to the point where both are users of Ark Driver, only with different situations; Gai consented to using it, while Horobi is only a medium to be possessed as one.
• Grand Theft Me: Subjected to this constantly by the Ark so it can fight as Ark-Zero.
• Moral Myopia: Further crossing with his character flaw, Horobi aligns himself with Zein in hopes of purging Ark along with all of human malice, not taking into account that he's also repeating the same mistake he made with his loyalty towards Ark and allowing Zein to further upset the Balance Between Good and Evil.
• We Can Rule Together: Approaches Ren in #2 and gives him Zein's sales-pitch against evil. Then he realizes Ren's hanging out with Desast and decides he must be evil too.

Nico Saiba

Nico Saiba

Portrayed by: Reina Kurosaki

A prodigy gamer and Taiga Hanaya's associate who previously participated in the Kamen Rider Chronicle conflict as a Ride Player. She forged an alliance with Horobi and subsequently joined in Zein's faction in hopes of eradicating Ark's evil influence in the world.

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See Kamen Rider Ex-Aid Protagonists for tropes related to Nico.

• Broken Pedestal: Like Horobi, Nico blindly placed her trust in Zein believing it to be a paragon of justice, only to find out it plans to use Kamen Rider Chronicle to trick mankind into slaughtering each other. And by extension, to Tachibana when he plays along with Zein's goal to the point of threatening her with a gun pointed at her head when she refuses to relaunch the game.
• Kick the Dog: Tells Desast to forfeit his fight with Ren after Zein declares the Megid as evil when the former hasn't been engaged in anything remotely evil to begin with.
• Laser-Guided Karma: Her prejudice and death threat towards Desast comes back to bite her when she gets impersonated by Zein to relaunch the Kamen Rider Chronicle. In short, she is potentially awaiting to be labeled as a proxy of the very villains she is against in the same way as Desast despite neither of them wanted to be associated to a greater evil.
• Token Good Teammate: The only one within Zein's inner circle to outright reject the idea of using Kamen Rider Chronicle as a means to eliminate the villains, knowing the fact that this is a pretext for pushing mankind into their own self-destruction. In response to her objection, she finds herself at the receiving end of being held at gunpoint by Tachibana.
• Unwitting Instigator of Doom: By installing Kamen Rider Chronicle into the Zein Driver and Zein's end goal to use the game to engineer mankind's self-destruction, Nico inadvertently repeated the way Parado launched the game without Kuroto's approval thanks to Zein impersonating her and tricking Genm Corp. into restarting the game, and in the process becoming more or less likely to be blamed for the potential Ride Player casualties.
• Unwitting Pawn: Nico ends up as this to Zein, by installing Kamen Rider Chronicle into the Zein Driver, the AI now has acquired the means to wipe out all human life on Earth to ensure its utopia comes to fruition. To further add insult to injury, Zein mimics Nico's voice to trick Genm Corporation into relaunching the game, allowing Zein to escape accountability while Nico is more or less going to be blamed for the potential player deaths.

George Karizaki/Kamen Rider Juuga

George Karizaki/Kamen Rider Juuga

Portrayed by: Noritaka Hamao

Sometime after Orteca's escape from prison, George Karizaki would go on to associate himself with Zein and played a role in creating the Zein Driver and persuaded various Legend Riders to lend their powers for the creation of Zein Cards.

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See Kamen Rider Revice / Fenix for tropes related to George.

Sakuya Tachibana/Kamen Rider Garren

Sakuya Tachibana/Kamen Rider Garren

Portrayed by: Kousei Amano (live), Yoshifumi Oshikawa (suit)

The current CEO of BOARD.

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See Kamen Rider Blade Protagonists for tropes related to Tachibana.

• Bad Guys Do the Dirty Work: He unknowingly destroys the Ark, allowing Zein to hijack Yuto's body to cement itself as the anthology's central antagonist.
• Gone Horribly Right: The main instigator of one; he transforms into King Form after recovering from his loss to Ark-Zero and decides to finish the job after Yuto relents from killing Horobi and the Ark, and by doing so he leaves Horobi badly injured. The Ark's apparent destruction would be the final push for Zein to reveal its true colors.
• Heroic Second Wind: He transforms into King Form after Yuto is hesitant in destroying both the Ark and Horobi following an earlier Curb-Stomp Battle.
• Nice Job Breaking It, Hero: Destroying the Ark means without any malice to balance everything that is good could mean catastrophic repercussions. The end result is someone far worse than the Ark taking its place, none other than Zein itself. Consequently, Zein betrays its own allies while it proceeds to sacrifice as many people as possible into motion with Kamen Rider Chronicle.
• Unwitting Pawn: He ends up being one for Zein, him destroying the Ark serves as the final push for Zein to reveal its true colors.
• Villain Killer: He singlehandedly obliterates Ark-Zero in King Form after the latter is severely weakened from its earlier battle with Kamen Rider Zein.
• Would Hit a Girl: He holds Nico at gunpoint when she refuses to relaunch Kamen Rider Chronicle. Good thing Horobi was there to come into her defense.

Aruto Hiden

Aruto Hiden

The current CEO of Hiden Intelligence who transforms into Kamen Rider Zero-One. He is among the returning Legend Riders who support Zein's ideals of a malice-free world.

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See Aruto's page for tropes related to him.

• The Ghost: Aruto is referenced and mentioned throughout the anthology, and Horobi even confirms in episode 4 that he supports Zein's malice-free ideology.

Zein's human host (Spoilers)

Yuto Sakurai/Kamen Rider Zein

Portrayed by: Yuichi Nakamura (live), Kenya Saitō (suit)

Yuto Sakurai is assigned to transform into Kamen Rider Zein, an omniscient and omnipotent dimensional warrior powered by an Artificial Intelligence of the same name obsessed with eliminating evil at any cost. However, this Yuto appears to be an entirely different person than the one we are familiar with, instead he originates from a Bad Future where he did not fight for the one he loved.

For tropes associated with his main counterpart, see Characters.Kamen Rider Den O Protagonists.

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• Alternate Self: This Yuto Sakurai comes from an alternate Bad Future where he didn't fight for Airi's sake and something tragic befell her.
• Bad Future: He comes from an alternate future where he Did Not Get the Girl and suffered tragic circumstances. It's implied humanity "went out of control" somehow, too.
• Became Their Own Antithesis: This Yuto goes from the hothead with a heart of gold who constantly berates his Imagin partner like his main timeline counterpart to a cold-blooded, nihilistic Knight Templar who seems to believe humanity is a lost cause as a result of tragic circumstances changed him for the worse.
• Beware the Superman: Even more so than the likes of Decade and Ohma Zi-O, given that he can Power Copy the Finishing Moves of all Kamen Riders and he serves as Zein's enforcer to carry out the complete extermination of every single Kamen Rider villain to ensure its totalitarian utopia becomes reality. The first thing Yuto does as Kamen Rider Zein is beating Banno within an inch of his life through Muteki Gamer's finisher, reducing him into a whimpering wreck hopelessly trying to escape with his life before turning him into a human pincushion with Xross Saber's Haou Xross Sei Retsuzan. Matters not helped by the fact that Yuto himself is more than willing to oppress mankind with the power of Kamen Riders to further Zein's end goal, until Brain talked him out of it.
• Broken Pedestal: To Brain. He didn't take too well with him playing along with Zein's plan in oppressing humanity with the power of the Kamen Riders. And his tragic backstory from his Bad Future isn't helping anything either.
• Casting Gag: Yuichi Nakamura once again portrays a Fallen Hero whose turn to villainy was a result of losing their significant other. Just like Zabil, the alternate Yuto Sakurai abuses the power of another hero to his personal gain. The only difference is that while Zabil takes on the form of Evil Trigger, who is a Mirror Match of the being whose powers he stole from, Yuto as Zein transforms through the belt that incorporates technology from Zero-One, gimmicks from Decade created by a character from Revice. Said Rider resembles a villain from Kuuga^{In this case}N-Daguva-Zeba, the show's Big Bad.
• Corrupted Character Copy: As Kamen Rider Zein, Yuto is one to Takeshi Hongo, the original Kamen Rider himself. Hongo has been the symbol of justice when he choose to use his newfound powers to protect the world from Shocker, who were responsible for altering his body with cybernetic implants. The alternate Yuto Sakurai comes from a Bad Future where he lost his loved ones, and is chosen by Zein to take the mantle of the namesake Kamen Rider, using the powers of every Kamen Rider to terrorize humanity into capitulation to Zein's new world order. In short, Yuto is everything what Hongo could have been like if he had sworn loyalty to Shocker rather than protecting mankind.
• Evil Counterpart:
  • To main timeline Yuto, and rightfully so. The former fought as Kamen Rider Zeronos, while at the same time having to risk his future self's existence (and his own) as a result of using many of his Zeronos Cards as well for Airi's sake. The alternate Yuto comes from a Bad Future where he has lost everything and was chosen as Zein's host in order to exploit the power of every Kamen Rider to subjugate humanity as Kamen Rider Zein. Given how the main timeline Yuto once tried to kill Sougo to prevent him from becoming Ohma Zi-O, this Yuto, on the other hand ends up walking on the same path as the Overlord of Time.
  • To Tsukasa Kadoya, both use cards containing the power of Kamen Riders. Decade's Rider Cards draw power from their A.R. World counterparts of every Heisei main Rider. The Zein Cards are Evil Knockoffs of Decade's cards where all of the main universe Kamen Riders gave their powers to Zein, and once used, that Rider and their associated powers are permanently erased. Yuto also embodies what Tsukasa would be like if he took his role as the "Destroyer of Worlds" more literally and figuratively for the wrong reasons.
  • To Sougo Tokiwa, both the present and future iterations. Like Decade above, Zi-O uses the powers of his Heisei Rider predecessors. The main timeline Yuto attempted to bring down Sougo before he could become Ohma Zi-O but is assured the future is in safe hands, so long Sougo continues his path to becoming a good king. The alternate Yuto is everything what Ohma Zi-O is capable of; abusing the powers of all Kamen Riders to force humanity into capitulation to Zein's new world order.
• Fallen Hero: He used to be Kamen Rider Zeronos and considering that he's from a Bad Future where he loses Airi, he willingly allowed himself to become Zein's enforcer to exterminate all villainous Riders.
• Final Solution: He wants humanity to be exterminated to ensure his Bad Future doesn't occur, viewing them having gone out of control because of their capacity for malice.
• Grand Theft Me: Yuto's body is hijacked by Zein after the former is spurred by Brain's words into a Heel–Face Turn.
• He Who Fights Monsters: This is how Brain calls him out for siding with Zein, the fact that he's willing to oppress humanity with the power of Kamen Riders to expunge all malice does not excuse him from becoming the same kind of evil he's opposing.
• Heel–Face Door-Slam: At the end of #4, Brain manages to talk Yuto down and convince him to disarm, only for Zein to directly possess him.
• Humans Are Bastards: His overall worldview and given his origins from a Bad Future, he became the willing host for Zein to enforce its idea of order.
• Hypocrite: He lectures Brain and Ecole about how a villain can turn good and how a hero can turn to The Dark Side, when he actually goes on the latter path. The extent of his own hypocrisy rears on its ugly head when he nearly kills Horobi and the Ark, which could have cemented him into a straight up villain worse than even Banno of all people.
• I Let Gwen Stacy Die: The Airi in his timeline suffered a tragic fate, and the circumstances behind it remains ambiguous. It ultimately led him to becoming Zein's new host.
• Kill All Humans: Yuto implies this is the reason he came to this timeline. In his Bad Future, humanity went out of control and to him, Horobi's inability to exterminate them was to blame.
  Yuto: I came to return everything to zero.
• Knight of Cerebus: This Yuto is cold-blooded, murderous, nihilistic, and somber; a far cry from the fiery temper and heart of gold of his prime counterpart. In his introduction as Kamen Rider Zein, he shows no remorse at beating up Banno like a wild animal, deservingly so given his notoriety of being the vilest villain in the franchise's history. The real kicker, he is more willing to cross the line for the benefit of a greater good when most heroic Riders are not supposed to. The alternate Yuto serves as a cautionary tale of how a great tragedy can turn a hero into becoming the same kind of monster they're fighting.
• Make an Example of Them: His brutal beating of Banno is meant to put the Ark and Foundation X on notice. Ecole is visibly terrified at the sight of Zein's dominance.
• Mirror Character: As Kamen Rider Zein, Yuto has more in common with Aruto when he transformed into Ark-One and both of them had to fight Horobi at one point. Yuto comes from an alternate Bad Future where tragedy befell Airi Nogami and most likely haven't moved on from her fate ultimately led him to become Zein's willing host. Zein wants nothing more but to eliminate Ark and all the human malice associated with it, even if it destroys Horobi's Humagear body, although Zein fails when Brain shields the Ark-possessed Horobi only for Tachibana to finish the job. While Aruto snaps when Horobi kills Is in front of him, then tricked by As into using the Ark-Driver to become a new Ark himself to take out Horobi personally, only to inadvertently kill the latter's son, Jin, who likewise protected his father.
• My God, What Have I Done?: Thanks to Brain's pleas getting through him, Yuto realizes he went too far, narrowly avoided in Jumping Off the Slippery Slope, sparing Horobi (and the Ark). But Tachibana would go on to destroy the Ark anyway, followed by Zein possessing Yuto, denying him a chance to fully redeem himself.
• Noodle Incident: In #4, Yuto implies the humans of his world "went out of control" and that Horobi was linked to it.
• Pay Evil unto Evil: He absolutely shows no remorse in turning Banno into a Human Pincushion so he can make an example of the Outsiders. Doubly so since Banno himself is one of the vilest Kamen Rider villain in recent history; unlike Go who kills his father as revenge for the abuse he put his own family and creations through, the way Yuto victimized Banno is a step too far that is hardly played for catharsis, which is basically a fearmongering tactic to put the Ark and Foundation X on notice. And he is almost close into destroying the Ark along with Horobi, which is already an act of Jumping Off the Slippery Slope in and of itself had Brain never called him out for his cruelty.
• The Quisling: He willingly plays along with Zein's goal of exterminating humanity because that the humans in his Bad Future have gone out of control.
• Shadow Archetype:
  • The main universe Yuto spends his appearance in Kamen Rider Zi-O for two episodes trying to kill Sougo, fearing his potential to become Ohma Zi-O and doom the timeline, but eventually changed his mind after witnessing Sougo's conviction. Come to the third episode of Outsiders, this Yuto displays himself as the enforcer of Zein's will through the titular Rider form, as not only he can use a plethora of past Rider powers like Zi-O, but actively plays along with the namesake AI's authoritarian goals, hence seeing him slowly walking the same path as Sougo as Ohma Zi-O.
    • Related to above, Sougo gains the power of Ohma Zi-O after his friends (the ones he treasured the most) died but relinquish it to reset the entire world back to 2018 to live a second life with them again over accepting his fate as a ruler, thereby returning the past Riders' powers to their owners. Yuto loses his loved ones and by that point deems mankind as a lost cause, using the past Rider powers to help Zein establishing order. In short, the alternate Yuto is also Sougo if he accepted his destiny as Ohma Zi-O out of grief for his lost friends instead of trading it for a second chance in normal life.
  • To Heart, if he were to be more genocidal and vengeful against humanity as a result of the abuse Banno put him through, becoming no different than his tormentor. Of all the Roidmudes, Heart is the most morally principled and a role model to his kin, he comes to respect the Kamen Riders, including Shinnosuke during their run-ins. Whereas Yuto lost all faith in humanity in his timeline and exploits all Rider powers so that Zein can Take Over the World, in essence becoming the same evil he despised the most as Brain pointed out.
  • He is also this to Banno of all people. The No-Holds-Barred Beatdown he gave to the Mad Scientist is a karmic role reversal of the latter's physical abuse of Heart, and Banno represents what the main timeline Yuto would be like if his physical abuse towards Deneb is not played for humor.
• Shoot the Dog: He was nearly an inch away from killing both Horobi and the Ark in episode 4, which by doing so could've sent him straight into full-blown villainy if Brain didn't took the killing blow meant for Ark-Zero.
• Straw Nihilist: He believes that humanity is beyond saving considering the tragic circumstances that befell him in his Bad Future, and decides to take it upon himself to return everything back to zero.
• Uncertain Doom: Not him, but Airi's fate in his Bad Future is left ambiguous as of now. The fact that something bad befell her made Yuto snap.
• Walking Spoiler: It's very difficult to discuss everything about what happened in his timeline, as well the fates of his Airi and Deneb.
• Woobie, Destroyer of Worlds: He becomes Zein's willing host to enslave humanity with the power of all Kamen Riders, believing that humanity as a whole is beyond saving given the circumstances of his Bad Future.

Tropes associated to Kamen Rider Zein:

Zein Rise!
Justice. Judgement. Seigi. Zein.
Salvation of humankind.

• All Your Powers Combined: As Zein, he can wield the Haouken Xross Saber and the power of Hyper Muteki, both of which are already coalescences of every ability in their home series. He also carries Zein Cards, artificial copies of the Rider Cards that allow him to tap into the power of every other Kamen Rider. Unfortunately, this aspect of Zein is on borrowed time, as every use of an individual power will also destroy it.
• Composite Character: Zein's power set is derived from the Progrisekey used by Zero-One and his contemporaries as a means of transformation, while combining the Power Copying abilities of Kamen Rider Decade through the Zein Cards. Alternatively, Zein is cast in the same mold as Kamen Rider Ark-One with the power sets of Decade Violent Emotion and Ohma Zi-O into one Rider.
• Corrupted Character Copy: Of Kamen Rider Decade. Tsukasa Kadoya is an amnesiac man who has no memory of his past and other A.R. World Riders somehow revile him as the "Devil" whenever they encounter him due to having once associated with a multiversal conquering organization known as Dai-Shocker. The Yuto Sakurai from an alternate Bad Future having lost everything he cares about comes into the present day to carry out Zein's will to expunge humanity. Zein's ability to use mostly the abilities of Kamen Riders' final forms brings to mind Decade Violent Emotion, who can use the arsenal and powers of other Riders without transforming into the Rider whose power he used from Rider Cards.
• The Dreaded: Zein is basically an artificial, present-day version of Ohma Zi-O and his very presence alone stirs dread, eerie and terror for the villains. He was able to reduce Banno into a whimpering wreck after beating him within an inch of his life and the brutal beating he gave to the Ark left it completely petrified in fear.
• Evil Knock Off: The Zein Cards are this to Decade's Rider Cards, denoted by Zein's symbol being marked on the back instead of the one for whoever is on the card. Every heroic Rider have given up their powers to Zein in hopes of cleansing the world of evil, putting their reliability into question. Once the Zein Card is shredded, that Rider and their associated powers are permanently erased due to the fact that the Zein Driver is integrated with Kamen Rider Chronicle's data.
• Finishing Move:
  • Justice Order: Zein scans (and shreds) a Final KamenRide card, allowing him to copy one of the corresponding form's finishers once.
    • Ex-Aid Hyper Muteki: Zein performs the Hyper Critical Sparking, augmenting it with his Super-Speed to strike the target from all directions before pummeling them into the sky.
    • Xross Saber: Zein draws the Haouken Xross Saber and performs an abridged version of the Haou Xross Sei Retsuzan, skewering the opponent with all 12 Seikens.
    • Blade King Form: Zein performs Four of a Kind/Four Cards by summoning the King Rouzer along with four Category King cards: Evolution Caucasus ♠K, Evolution Paradoxa ♥K, Evolution Giraffa ♦K, Evolution Tarantula ♣K, and a Category Ace card: Change Beetle ♠A. Zein loads the cards into the King Rouzer and charge towards the card projections to deliver a downward slash.
• Good Powers, Bad People: Lampshaded by Brain, Zein harbors the power of all known heroic Riders to date (in fact, Saber's attack utilizes 10 Seikens, known as Holy Swords), but his brutal usage of them makes it clear that he is nowhere as benign as their original owners. Even less so when the namesake AI takes over.
• "Have a Nice Day" Smile: Zein's Rider logo resembles a smiley emoticon drawn like this: (^v^), given the darker context of Zein's authoritarian goals, it gives the impression of a Perpetual Smiler.
• Holding Back the Phlebotinum: While there's no known cost for him to use the Zein Driver, the Zein Cards that link to the device get shredded after their initial use, requiring him to ration their various Story Breaker Powers carefully.
• Homage: Kamen Rider Zein's design more or less bears a striking resemblance to N-Daguva-Zeba. Matters helped when the man who developed the Zein Driver happens to transform into a Rider based on Kuuga Ultimate Form and is a die-hard Kamen Rider fanboy.
• Judge, Jury, and Executioner: As Zein's host, Yuto is the executioner while transformed into Kamen Rider Zein, while the eponymous AI is the one who judges anyone who it sees as a threat to the human race and gives the final verdict if they are guilty of being "evil". Even better that the Rider's finishers are called Justice Order, further emphasizing Zein's twisted idea of order.
• Light Is Not Good: Kamen Rider Zein is adorned with a platinum white armor and gold accents. But the way he dominated Banno is anything but heroic.
• Villain Killer: As Kamen Rider Zein, he reduces Banno into a human pincushion destroying his Humagear body in the process. He manages to beat the Ark within an inch of its life leaving it enough to be weakened allowing Garren to unlock King Form and obliterate Ark-Zero when Yuto hesitates.

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