History Characters / KamenRiderBuildToutoGovernment

* EvilIsPetty: When Gentoku threatens him at gunpoint to make him a Rider, he forces his old employer to kneel down and ''beg'' for him to do so. [[KickTheSonOfABitch And then he]] ''[[KickTheSonOfABitch doesn't]]''.

[[folder:Nariaki Utsumi/Night Rogue II/Kamen Rider Mad Rogue]]
!!Nariaki Utsumi

!!!'''Portrayed by:''' Joji Kokubo

!!Takumi Katsuragi
!!!'''Portrayed by:''' Yukiaki Kiyama
[[quoteright:210:https://static.tvtropes.org/pmwiki/pub/images/takumi_katsuragi.png]]

The researcher originally in charge of studying the Pandora's Box, a brilliant man known as "The Devil's Scientist" by his colleagues. Ryuga was arrested for his murder prior to the series, and discovering the mystery behind Katsuragi's murder is his main motivation.

He was a founding member of Faust, the original planner of Project Build, and most importantly, [[spoiler:''the true identity of [[TheHero Sento Kiryu]]''.]]

* AntiHero: Once his full motivations are revealed, it's clear that Katsuragi was seeking a good end, but for vengeance rather than justice. Unlike his current personality as Sento, Katsuragi is willing to get his hands dirty in order to defeat the likes of Kaisei Mogami and Evolt, even as far as to steal Ex-Aid's powers or try to kill the yet-to-be awakened Ryuga just to achieve his goals, but that same willingness to do anything to kill Evolt was what let the snake take advantage of Katsuragi's brilliance to help get his plans rolling.
* BackFromTheDead: Either as a side-effect of his possession or as a deliberate act of spite, Evolt's theft of Sento's body causes Takumi's memories and personality to return and Sento's to vanish. It only lasts for a few episodes before Takumi willingly "dies" a second time.
* CatchPhrase: Episode 39 shows that Sento's catchphrase "Isn't it great? Isn't it amazing? Aren't I a genius?" started with Katsuragi, but he delivers it in a much more arrogant manner.
* ColdHam: He loves science just as much Sento, but since he is stoic and reserved compared to his much more excitable other self, he naturally expresses it in a way as cold as to give someone a frostbite.
** In ROGUE special, he bolts towards the research equipment at Faust's base in the same way Sento typically reacts to stuff that interests him, but his expression doesn't change nor does he say anything.
** He has the same victorious routine after inventing something as Sento has, but performs it without any childishness or excitement.
* ComfortFood: Tamagoyaki [[note]]basically an omelette served in rolls[[/note]] prepared by his mother. He apparently liked it so sweet that it's unbearable for anyone else to eat.
* CreativeSterility: [[DownplayedTrope Of a sort.]] He's certainly not starved for ideas, but he's so stuck in his ways and distrusting of others that he can't properly use Build Genius and ultimately can't utilize ''the Build System itself'' because his emotional mindset is too dulled to bring out its full power. His [[TalkingToThemself conversation with Sento]] in a representation of his mind shows formulas and gears stuck statically in place that only start moving again once he puts Sento back in the driver's seat. The real fault in his creativity, however, is one he shares with Sento: they both respond to problems by building weapons instead of thinking about how to use the Rider System and its components constructively, which blinded them both to the real functionality of the Hazard Trigger.
* DissonantSerenity: His eager and professional demeanor never falters during his device showcase videos, even when he's talking about how some of them have lethal, mind-destroying side effects. This partially carries into Sento's habit of using this state as a defense mechanism in traumatic situations.
* EveryoneHasStandards:
** Even for Katsuragi, the Hazard Trigger was too much, as was the discovery of Stalk and Ryuga's shared true identity. The real reason he brought both to his house was to try and kill them.
** Near the end of the first part of the ''ROGUE'' miniseries, he's noticeably uncomfortable when Gentoku repurposes his underground research facility into the starting point of Faust.
** ''Heisei Generations FINAL'' reveals that he helped build Kaisei Mogami's Enigma device, and even used it to travel to the [[Franchise/KamenRider main Kamen Rider universe]] and steal Emu Hojo's powers, but the moment he found out about Mogami's plan to forcibly merge the two worlds (which would destroy them both) he tried to pull the plug.
* {{Foil}}: It's clear that he and Sento are two completely different people/personalities when you break it down.
** Relationships: Sento, despite his smug behavior, has complete trust in his allies, cares for Misora as a clear friend, and despite bickering with Ryuga several times, they are clearly best friends. On the other side, Takumi trusts nobody, sees Misora as nothing but a means to create [=FullBottles=], and was actively ''trying'' to kill Ryuga due to the latter containing Evolt's [=DNA=].
** Use of the Build Station. Even though Takumi built the Build Driver and powers, he was unable to handle the more powerful forms Sento created, and had to adjust the [=RabbitRabbit=] form for his own goals. Sento had at least a year to train with the Build system, went through multiple different Best Matches with different abilities, and was easily able to adapt to any situation.
** And finally, their beliefs. Sento wanted to use the Build system as a way to ''protect'' people, and believed that science should be used to help instead of destroying. Takumi wanted to use the Build system to defeat Evolt, which turns into a plot point when he could not use the Genius [=FullBottle=] as his desire was not compatible with Sento's sense of justice.
* GeniusSweetTooth: As noted above, Takumi's preferred preparation of Tamagoyaki is considered to be very sweet compared to how it is usually served and him fulfilling the genius aspect serves little explanation given his scientific background and his hand in creating the system used by the Riders.
* GoodIsNotNice: When his memories return late in the series, his primary goal is to defeat Evolt to save humanity. However, he dismisses anyone of "lesser" intelligence, treating Sento's friends and allies as little more than gibbering chimps and refusing to hear any debate about sparing Banjou's life because they can't offer it in a logical manner.
* HeelFaceDoorSlam: Played with. He attempted to quit Faust and kill both Blood Stalk and Banjo upon discovering that they were the mind and body of Evolt, only for Stalk to have outplayed him by swapping Katsuragi's Build Driver for the nonfunctional prototype. Stalk then wiped Katsuragi's memory and changed his appearance, turning him into Sento. He still ended up becoming a good guy, but in a way that, initially, served Stalk's plans rather than ruining them.
* HesBack: In the absolute worst way. Raising his Hazard Level into the ''[[BeyondTheImpossible 6.0 range]]'' and subsequently being possessed by Evolt restored his memories at the cost of Sento's personality disappearing.
* HowDoIShotWeb: To his frustration, he's barely able to use Sento's upgrades due to his lack of experience despite having been the major architect of the entire Rider System.
* LikeFatherLikeSon: Turns out his father was also involved in human experimentation, with Ryuga as a test subject.
* LastChanceToQuit: The usually rabid and reckless Gentoku gave him ample opportunities to scrap Faust before they went past the point of no return, but Katsuragi pressed on anyway, believing their experiments, as monstrous as they would inevitably become, would benefit human civilization in the long run.
* MadScientist: He was the first to conceive of Nebula Gas technology, and at least for some period he was entirely comfortable with human experimentation. It still shows up in his new personality, Sento Kiryu, but to a lesser degree.
* MyGodWhatHaveIDone: After his return, he dissolves his relationship with Gentoku once he learns that in spite of all they had sacrificed to create the Rider System, the nightmare scenarios they tried to prevent with its usage (Evolt's return to power and a Japanese civil war respectively) still came to pass.
* NotWhatItLooksLike: ''Heisei Generations FINAL'' reveals that he was the Build who appeared in ''Ex-Aid: True Ending'' and stole Emu's powers, seemingly being his usual "Devil's Scientist" self. Later in the movie, Sento finds Katsuragi's notes and discovers that he was trying to ''save'' Ex-Aid's powers, believing that Hyper Muteki was the only thing capable of stopping Mogami's plans but realizing that his powers would be affected by the two worlds merging.
* PosthumousCharacter: Initially alleged to be dead before the show even begins, before it's revealed that he was TheHero all along.
* PowerIncontinence: During his return and loss of his memories as Sento, Katsuragi realizes that he can't keep up with the current Build upgrades.
* TheRedBaron: "Devil's Scientist".
* TheReveal: While the audience had plenty of reason to guess it beforehand, #15 finally confirms that Katsuragi lives on as Sento.
* SplitPersonalityMerge: Averted as the solution to his and Sento's situation: after Sento becomes their dominant personality again, he gets Katsuragi's childhood memories, but not the ones from his adulthood. Instead, Katsuragi's personality containing those memories sticks around as a SpiritAdvisor.
* TheStarscream: He worked with Faust while intending to kill Evolt from the very beginning to avenge his father.
* TheStoic: In life, he was phenomenally [[CannotSpitItOut bad at expressing his emotions]]. He even kept an even, level face while eating his favorite food. That being said, it was just expressing those emotions he was bad at. He still dearly loved his mother, despite never telling her such, and left her a coded message in his final message thanking her for giving him life.
* StrawVulcan: During his return in #37-39, he dispassionately dismisses the rest of the cast's silly antics and belief in friendship as nonsense straight out of a shonen manga while planning out a way to destroy Evolt...and Banjo, whom he believes will become another Evolt if left unchecked. However, despite having created the Genius Bottle himself, he's unable to use it because he doesn't have the right emotional mindset; after he regains all his memories and becomes the emotional Sento Kiryu again, the Genius Bottle works perfectly, creating [[SuperMode Build Genius Form]].
* SurprisinglyRealisticOutcome: When he fights as Build in Episode 38, he can't handle the various upgrades, weapons and tweaks that Sento made in his "absence" as the furthest he got was ''[=GorillaMond=]''. He also didn't realize that the Pandora's Box panel doesn't work as a power-up because it's meant to simply increase the user's Hazard Level fast enough for them to perform a SuicideAttack.
* ThenLetMeBeEvil: It's shown in a flashback that Katsuragi accepted that his desire to advance the world through Faust and Project Build would lead to suffering, but such was his fury and resolve that he declared he would even sell his soul to the devil if it was for the sake of research.
* WalkingSpoiler: Just like Himuro, it's impossible to discuss his role in this series without spoiling huge plot twists. After all, he ''is'' our protagonist.
* WellIntentionedExtremist: Katsuragi is implied to have had sympathetic motivations for creating Faust, but the monster he created grew far beyond his control. When he learned who Evolt was, he tried to kill him and his other host Banjo before he could set into motion his plan to destroy the world.
* WhosLaughingNow: Furious that the nation drove his father to suicide by blaming him for the Sky Wall Disaster, he decided to reclaim his family's honor by creating weapons derived from the anomaly's Nebula Gas deposits.
* WouldHurtAChild: He exploited a preteen Misora's abilities dozens of times to create his [=FullBottes=]. His incredibly backhanded apology for it when he returns stuns the usually fierce girl with its sheer glib audacity, much to Ryuga's ire.
[[/folder]]

[[folder:Shinobu Katsuragi (SPOILERS)]]
!!Shinobu Katsuragi/Kamen Rider Build
!!!'''Portrayed by:''' Joji Kokubo


[[quoteright:325:https://static.tvtropes.org/pmwiki/pub/images/shinobu_katsuragi.png]]
Takumi Katsuragi's father and the lead scientist on the fateful Mars expedition, Shinobu was blamed for the ensuing Sky Wall disaster and driven to suicide as a result. His suicide drove his son Takumi to the path of revenge that would bring about Project Build.


In truth, before his supposed death, Shinobu was blackmailed by the newly-arrived Evolt into fixing the broken Evol Driver, and his research notes on Evolt, the Evol Driver, and the Pandora Box prove crucial to the creation of the Genius [=FullBottle=]. ''Supposed'' death, because evidence soon comes to light that like his son, rumors of Shinobu's death have been greatly exaggerated.
----

* HeelFaceDoorSlam: {{Subverted|Trope}}. He tries to convince Sento that there was another path to take and to not end up like he has, but is shot by Gentoku before he could say anything else. He survived, but rather than turn face, returns to working with [[Characters/KamenRiderBuildNambaHeavyIndustries Namba Heavy Industries]]. He looks like he might turn again as Namba's ambitions escalate into madness, but his indoctrination is too strong for him to do more than look a bit worried before going along with whatever his master desires.

[[quoteright:210:https://static.tvtropes.org/pmwiki/pub/images/krbu_guardian_touto.png]]

See his page in Characters/KamenRiderBuildProtagonists

[[folder:Guardians]]
!!Guardians

----
* AIIsACrapshoot: Their focus is obscenely single-minded, and they aren't especially intelligent, such that they can all decide to only target Build even though there's an active and dangerous Smash ''right in front of them''. Making matters worse is that Stalk, and presumably anyone else working with Namba Heavy Industries, can take control of any Guardian at any time. Subverted as the guy they're taking orders from was the guy sending out Smash to begin with and that's exactly what Namba designed them to do.
* BayonetYa: Guardian's rifles are adorned with a blade at the end.
* BoringButPractical: They have the potential to defeat Smash by themselves. It just takes a lot of bullets. ''A lot'' of bullets.
* ButtMonkey: In ''Heisei Generations FINAL'', the Nebula Bugsters goons are swapped out for Guardians in the film's last act so that all the Riders get opponents they can beat since Bugsters are immune to attacks not backed by a Game Driver or weaponry associated with such.
* CombiningMecha: A whole group of them can combine into a larger mecha.
* CoolHelmet: The Guardians do have pretty cool helmet designs.
* ImperialStormtrooperMarksmanshipAcademy: Whoever designed their targeting systems needs to be fired immediately. That said, their effectiveness against anyone but the protagonists (who Faust explicitly wanted alive for their own ends) imply their seemingly poor aim might just be for PragmaticVillainy in those cases.
* JustAMachine: The heroes have no qualms destroying them, often in creative ways.
* ManchurianAgent: Namba Heavy Industries, as part of their pact with Faust, included a VillainOverride function allowing Night Rogue and Blood Stalk to hijack them at a moment's notice.
* MechaMooks: For every faction, with their ownership distinguished by their faceplates. Even Foundation X has some. All of them are produced and sold by Namba Heavy Industries, whose entire intent for starting the war was to sell weapons like them in the first place.
* RedshirtArmy: They're basically government-issued [[Series/KamenRider Shocker Grunts]].
* VillainOverride: Namba Heavy Industries included one in their design, allowing Blood Stalk and Night Rogue to take control of them whenever they want.

[[center: [- [[Characters/KamenRiderBuild Main Character Index]] | [[Characters/KamenRiderBuildProtagonists Protagonists]] ([[Characters/KamenRiderBuildSentoKiryu Sento Kiryu/Kamen Rider Build]]) | [[Characters/KamenRiderBuildFaust Faust]] | '''Touto Government''' | [[Characters/KamenRiderBuildHokuto Hokuto Government]] | [[Characters/KamenRiderBuildSeito Seito Government]] | [[Characters/KamenRiderBuildNambaHeavyIndustries Namba Heavy Industries]] | [[Characters/KamenRiderBuildMovieExclusiveCharacters Movie-Exclusive Characters]]]]-]

** [[spoiler:President Nanba (disguised as Midou) even calls him out on this in episode 32. When Taizan attempts to use Pandora's Box as a deterrent force to demand that Seito pull its forces out of Touto, Nanba laughs the threat off by claiming that a conscientious man such as Taizan who is fully aware of the destructive potential of Pandora's Box would never actually follow through on using it, meaning he can act as he wants without worrying about an effective reprisal.]]

* GoodParents: He loves his son and wants him to know it, but considering how Gentoku is a power hungry maniac, his attempts usually fall flat. Granted, he did disown Gentoku after getting to known about everything, but that was completely justified shock. He tries to talk it out the next time they meet even thought he is held at a gunpoint.

* BigGood: He's the only regional leader who's actively trying to fix things. [[spoiler:After Evolt was destroyed for good and the world is remade as [[RetGone if he never influenced Earth in the first place]], Taizan is now the Prime Minister of Japan as a whole.]]

** [[spoiler:Despite being held at gunpoint by Gentoku, who is now a veritable SuperSoldier, he doesn't beg for his life and his first action is to ensure the safety of his aides. He even tries to reconcile with Gentoku in a sincere manner rather than than disingenuously using it to bargain for his life.]]

[[center: [- [[Characters/KamenRiderBuild Main Character Index]] | [[Characters/KamenRiderBuildProtagonists Protagonists]] | [[Characters/KamenRiderBuildFaust Faust]] | '''Touto Government''' | [[Characters/KamenRiderBuildHokuto Hokuto Government]] | [[Characters/KamenRiderBuildSeito Seito Government]] | [[Characters/KamenRiderBuildNambaHeavyIndustries Namba Heavy Industries]] | [[Characters/KamenRiderBuildMovieExclusiveCharacters Movie-Exclusive Characters]]]]-]

* EvenEvilHasStandards: Played with. Juzaburo Namba's actions and escalating ambitions after the Seito representative duel leave Utsumi visibly unnerved, but it's not enough to overcome the brainwashing he's been indoctrinated with since childhood, and so he continues to go along with Namba's plans even knowing that what he's doing is wrong. He even takes a sort of twisted satisfaction in being put in a position where he can repeatedly take out his frustrations on Gentoku.

* BigGood: He's the only regional leader who's actively trying to fix things. [[spoiler:After Evolto was destroyed for good and the world is remade as [[RetGone if he never influenced Earth in the first place]], Taizan is now the Prime Minister of Japan as a whole.]]

The secretary to Gentoku Himuro and another aide to the Prime Minister of Touto, Utsumi is rarely seen without his boss. After seemingly being killed by Gentoku as a substitute Night Rogue, he's saved by Stalk and recruited to work for Namba Heavy Industries. In this role, Utsumi develops Hokuto and Seito's Sclash Drivers, recreates the Kaiser System to create the Bros, and takes the original Transteam Gun for himself to become the second Night Rogue. He later uses the Evol Driver together with the Bat and Engine Fullbottles to become Kamen Rider Mad Rogue after being driven insane by Evolto.

* BigDamnHeroes: [[spoiler:Shows up when Gentoku is about to fight the mimics Evolto generated of the Hell Bros, for what Gentoku thinks is making the fight 3-on-1. Then he promptly turns on the Hell Bro Mimics, at least entering an EnemyMine with Gentoku]].
* BodyBackupDrive: [[spoiler:The real reason Evolto gave him a copy of the Evol Driver was to make it so that he could use Utsumi as a host body in the event of his "death".]]

* BrainwashedAndCrazy: As a Namba Child he's been conditioned since childhood to be absolutely loyal to Namba himself. This works in Evolto's favor after he ''kills'' Namba, as Utsumi's unstable mental state causes him to snap and swear loyalty to Evolto instead.

* CrazyPrepared: [[spoiler:He designed Hell Bros with a deliberate weakness to the [=SameBike=] Best Match. He had no reason to ever think that Hell Bros would be used against him or Namba, but it pays off ''much'' later when he and Gentoku team up against a Mimic created by Evolto.]]

* CrouchingMoronHiddenBadass: After becoming Mad Rogue he spends most of his time either getting his ass kicked to show off new forms and power-ups or generally just a slightly more powerful enemy to fill out fights. [[spoiler:In the third-to-last episode he reveals that he was faking loyalty to gather data on Evolto's Phases to become even more powerful and avenge Namba. He actually keeps Evolto up against the ropes for a while before he gets too cocky and activates Phase 4, blowing out his own cybernetics.]]

* DespairEventHorizon: After Evolto kills Namba, Utsumi leaps over the edge, cracks a goofy grin and gleefully swears loyalty to Evolto, becoming Mad Rogue.

* TheDragon: After becoming Mad Rogue, he is effectively this to Evolto, acting as his enforcer and doing his dirty work whenever he doesn't feel like getting involved.
* DragonTheirFeet: While acting as Namba's assistant for a portion of the series, after Namba gets offed by Evolto, Utsumi goes on to serve him.

* FatalFlaw: His reliance on having superior weaponry and data. As Mad Rogue, he mainly relies on his Evol Driver boosting his capabilities. However, it's never enough to truly close the gap between him and the heroes since not only do they have higher Hazard Levels and/or equivalent technology, they also have much more combat experience than him. [[spoiler:In the end, his over reliance on the Evol Driver costs him dearly when he pushes his Evol Driver to Phase 4 in order to deal the finishing blow to Evolto only for the power to be too much for his cyborg body, interrupting him at the worst possible moment.]]

* FourEyesZeroSoul: Always seen wearing a pair of glasses, though he doesn't fully embrace the "Zero Soul" part until he [[SanitySlippage goes crazy]] and joins Evolto. [[spoiler:Somewhat subverted when it's revealed he was just biding his time until he could get revenge for Namba's death.]]
* ForcedToWatch: All he can do as Evolto kills Namba is helplessly watch over his tablet's live feed. This directly leads to his SanitySlippage and becoming Evolto's [[TheDragon Dragon.]]
* GoMadFromTheRevelation: The death of his "father figure" Juzaburo Namba in #38 seems to drive him over the edge. Evolto shows up and throws him Namba's walking stick while asking him if he wants "Do you want revenge for Namba, or to swear your loyalty to me?" Utsumi [[FlashBack flashes back]] to memories of his time under Namba...and then [[LaughingMad bursts out laughing]], breaks the cane over his knee, and signs up with Evolto with a grin on his face. Appropriately enough, his new form is named Kamen Rider ''Mad'' Rogue. [[spoiler:It's later subverted when it's revealed that this was all an act just so he'd have a chance to avenge Namba]].
* GoodAllAlong: [[spoiler:Er, Less Evil All Along, but it's revealed in #47 that he was only pretending to be on Evolto's side, if only for the chance to gather data to use against Evolto to avenge Namba. He still holds a grudge against Gentoku for what happened earlier, but he's more than willing to put aside that grudge if it means the chance to take down Evolt]].

* HeroicSacrifice: [[spoiler:Sacrifices himself to protect Gentoku and Sawa against a blow from Evolto. However, he's only protecting the Lost Bottle, since he still hasn't entirely forgiven Gentoku]].

* IFightForTheStrongestSide: Utsumi has no real will on his own and usually falls in line with whoever is directly in charge at the time such as Gentoku, Namba, and ultimately Evolto.

* OnlySaneMan: With the obvious exclusion of Sawa who is the only one who got out the sinking ship that is Namba Heavy Industries. Utsumi seems to be the only villain to openly question Evolto's methods. It's then blown straight to hell once Utsumi joins Evolto and becomes the oh so fittingly named Mad Rogue.

* SatelliteCharacter: The majority of his character revolves around his role as Gentoku's secretary, until his apparent death in #12 and his return in #18, at which point he switches to being Juzaburo Namba's satellite instead. Come #38, he's now ''Evolto's.''

* SuicidalOverconfidence: He charges Evolto with nothing more than a Transteam Gun ''untransformed'' and demands he stop opening Pandora's Box. He gets casually sent flying for his trouble.
* TookALevelInBadass: He actually gets to ''fight'' as Night Rogue in the [=YouTube=] specials, showing himself to be a great deal more cunning and analytical than Gentoku ever was. He later gets an even bigger upgrade after receiving an Evol Driver (which explicitly needs a Hazard Level of 5) from Evolto to become Kamen Rider Mad Rogue.

* AntiHero: Once his full motivations are revealed, it's clear that Katsuragi was seeking a good end, but for vengeance rather than justice. Unlike his current personality as Sento, Katsuragi is willing to get his hands dirty in order to defeat the likes of Kaisei Mogami and Evolto, even as far as to steal Ex-Aid's powers or try to kill the yet-to-be awakened Ryuga just to achieve his goals, but that same willingness to do anything to kill Evolto was what let the snake take advantage of Katsuragi's brilliance to help get his plans rolling.
* BackFromTheDead: Either as a side-effect of his possession or as a deliberate act of spite, Evolto's theft of Sento's body causes Takumi's memories and personality to return and Sento's to vanish. It only lasts for a few episodes before Takumi willingly "dies" a second time.

** Relationships: Sento, despite his smug behavior, has complete trust in his allies, cares for Misora as a clear friend, and despite bickering with Ryuga several times, they are clearly best friends. On the other side, Takumi trusts nobody, sees Misora as nothing but a means to create [=FullBottles=], and was actively ''trying'' to kill Ryuga due to the latter containing Evolto's [=DNA=].

** And finally, their beliefs. Sento wanted to use the Build system as a way to ''protect'' people, and believed that science should be used to help instead of destroying. Takumi wanted to use the Build system to defeat Evolto, which turns into a plot point when he could not use the Genius [=FullBottle=] as his desire was not compatible with Sento's sense of justice.
* GoodIsNotNice: When his memories return late in the series, his primary goal is to defeat Evolto to save humanity. However, he dismisses anyone of "lesser" intelligence, treating Sento's friends and allies as little more than gibbering chimps and refusing to hear any debate about sparing Banjou's life because they can't offer it in a logical manner.
* HeelFaceDoorSlam: Played with. He attempted to quit Faust and kill both Blood Stalk and Banjo upon discovering that they were the mind and body of Evolto, only for Stalk to have outplayed him by swapping Katsuragi's Build Driver for the nonfunctional prototype. Stalk then wiped Katsuragi's memory and changed his appearance, turning him into Sento. He still ended up becoming a good guy, but in a way that, initially, served Stalk's plans rather than ruining them.
* HesBack: In the absolute worst way. Raising his Hazard Level into the ''[[BeyondTheImpossible 6.0 range]]'' and subsequently being possessed by Evolto restored his memories at the cost of Sento's personality disappearing.

* MyGodWhatHaveIDone: After his return, he dissolves his relationship with Gentoku once he learns that in spite of all they had sacrificed to create the Rider System, the nightmare scenarios they tried to prevent with its usage (Evolto's return to power and a Japanese civil war respectively) still came to pass.

* TheStarscream: He worked with Faust while intending to kill Evolto from the very beginning to avenge his father.

* StrawVulcan: During his return in #37-39, he dispassionately dismisses the rest of the cast's silly antics and belief in friendship as nonsense straight out of a shonen manga while planning out a way to destroy Evolto...and Banjo, whom he believes will become another Evolto if left unchecked. However, despite having created the Genius Bottle himself, he's unable to use it because he doesn't have the right emotional mindset; after he regains all his memories and becomes the emotional Sento Kiryu again, the Genius Bottle works perfectly, creating [[SuperMode Build Genius Form]].

* WellIntentionedExtremist: Katsuragi is implied to have had sympathetic motivations for creating Faust, but the monster he created grew far beyond his control. When he learned who Evolto was, he tried to kill him and his other host Banjo before he could set into motion his plan to destroy the world.

In truth, before his supposed death, Shinobu was blackmailed by the newly-arrived Evolto into fixing the broken Evol Driver, and his research notes on Evolto, the Evol Driver, and the Pandora Box prove crucial to the creation of the Genius [=FullBottle=]. ''Supposed'' death, because evidence soon comes to light that like his son, rumors of Shinobu's death have been greatly exaggerated.

* AlwaysSomeoneBetter: He's this to Takumi and Sento, being able to not only repair the Evol Driver, but create a replacement [=EvolBottle=] for the one that broke on Mars, and even constructed a whole new Evol Driver almost as good as the original, though tuned down for a human. While the Genius [=FullBottle=] is made using Takumi's skills and Sento's purifier machine, it's built on a function of the Pandora Box that Shinobu discovered. He also created the [[PsychoPrototype Lost Bottles]], although even Takumi can't begin to fathom why his father would have done something so vile. It's eventually revealed that they exist for a project similar to what Takumi had previously explored with Kaisei Mogami: to eliminate Evolto and undo his actions by creating a MergedReality, using Evolto himself as the fuel source.

* AmbiguouslyEvil: Shinobu's actions at first appear unquestionably evil, but soon contain enough shades of stealth mentoring Sento that it's clear there's more to Shinobu than meets the eye. He disables Build by striking the Hazard Trigger, then uses [=NinninComic=]'s SmokeOut ability to teleport Sento to safety, all while delivering a speech that can be read as either EvilGloating or a legitimate warning. Sento later realizes that he can use the same trick on the Evol Trigger and starts wondering if his father showed him the trick on purpose so he could use it against Evolto.

* BigGood: Shinobu eventually turns out to be a secondary one after it's revealed that he's GoodAllAlong. While Vernage gave the heroes a fighting chance, it's Shinobu's actions that ultimately paved the way for Evolto's defeat. After making contact with Evolto, he elected to feign allegiance with him in order to study both him and the Pandora Box. Not only did this allow him to create the Rider System, but it also allowed him to learn of the Black and White Pandora Box Panels, allowing him to trick Evolto into sparing Earth for the time being with the promise of more power, and create a means by which Evolto could be destroyed and everything he did would be undone. While he never lived long enough to see the plan to through the end, he was able to entrust the plan to Sento, who was ultimately able to finish the job.
* EvilCounterpart: While not truly evil, Shinobu plays the role while being active on Evolto's side as another Kamen Rider Build.
* GoodAllAlong: As it turns out, he's been plotting against Evolto the entire time just waiting for his chance. Once Evolto's defeated by the other Riders he seals the Evol Driver in a canister to keep him from regenerating and reveals his plan to use the black Pandora Panel to do something to protect humanity. Unfortunately, Evolto had a backup plan and Shinobu is KilledOffForReal in retribution for his betrayal.

* IDidWhatIHadToDo: He worked with Evolto even though his plans would kill a whole lot of innocent people because if Evolto won, it would mean that ''everyone'' would die. Thus, he stuck close to Evolto in order to plot against him right under his nose.

* OutGambitted: He planned to trick Evolto into losing on purpose in order to complete the last Lost Bottles and then trap his Evol Driver inside a canister in order to prevent him from regenerating, and then use the Black Pandora Panel's warp travel abilities to hopefully find a more permanent solution. Unfortunately, Evolto was already suspicous of Shinobu and was smart enough to splinter off a part of himself to posses Utsumi, allowing him to confirm his suspicions, retrieve his Driver and claim the Lost Bottles and Black Pandora Panel.

* NotSoDifferent: Sees himself this way to Sento, and attempted to convince the latter not to end up like him before his death.

* NotSoDifferent: The more the audience learns about Katsuragi, the more it's revealed that he's not far off in personality from his new identity as Sento.

!!!Portrayed by: Meikyo Yamada

!!!Portrayed by: Kensei Mikami

!!!Portrayed by: Yuki Ochi (live) Yuji Nakata (suit)

* BigDamnHeroes: [[spoiler:Shows up when Gentoku is about to fight the Mimics Evolt generated of the Hell Bros, for what Gentoku thinks is making the fight 3-on-1. Then he promptly turns on the Hell Bro Mimics, at least entering an EnemyMine with Gentoku]].

* CrouchingMoronHiddenBadass: After becoming Mad Rogue he spends most of his time either getting his ass kicked to show off new forms and power-ups or generally just a slightly more powerful enemy to fill out fights. [[spoiler: In the third-to-last episode he reveals that he was faking loyalty to gather data on Evolto's Phases to become even more powerful and avenge Namba. He actually keeps Evolto up against the ropes for a while before he gets too cocky and activates Phase 4, blowing out his own cybernetics.]]

* OnlySaneMan: With the obvious exclusion of Sawa who is the only one who got out the sinking ship that is Namba Heavy Industries. Utsumi seems to be the only villain to openly question Evolto's methods. It's then blown straight to hell once Utsumi joins Evolt and becomes the oh so fittingly named Mad Rogue.

* SuicidalOverconfidence: He charges Evolt with nothing more than a Transteam Gun ''untransformed'' and demands he stop opening Pandora's Box. He gets casually sent flying for his trouble.

* ExplosiveOverclocking: [[spoiler: He was able to imitate Evol's various Phases, even up to Phase 4. However, this was too much for his cyborg body, and it results in his death.]]

!!!Portrayed by: Yukiaki Kiyama

* TheStarscream: He worked with Faust while intending to kill Evolt from the very beginning to avenge his father.

* StrawVulcan: During his return in Episodes 37-39, he dispassionately dismisses the rest of the cast's silly antics and belief in friendship as nonsense straight out of a shonen manga while planning out a way to destroy Evolto...and Banjo, whom he believes will become another Evolto if left unchecked. However, despite having created the Genius Bottle himself, he's unable to use it because he doesn't have the right emotional mindset; after he regains all his memories and becomes the emotional Sento Kiryu again, the Genius Bottle works perfectly, creating [[SuperMode Build Genius Form]].

!!!Portrayed by: Joji Kokubo

!!!Portrayed by: Tsukasa Honjo (Eita) and Ryo Yoshida (Shingo)

!!!Portrayed by: Taro Nakatani

!!!Portrayed by Meikyo Yamada

!!!Portrayed by Kensei Mikami

!!!Portrayed by Yuki Ochi (live) Yuji Nakata (suit)

!!!Portrayed by Yukiaki Kiyama

!!!Portrayed by Joji Kokubo

!!!Portrayed by Tsukasa Honjo and Ryo Yoshida

[[folder:Guardians]]
!!Guardians
[[quoteright:166:https://static.tvtropes.org/pmwiki/pub/images/krbu_guardian_touto.png]]
Robot soldiers created by Namba Heavy Industries and sold to all factions in Japan, and possibly worldwide. Touto uses them as the bulk of their peacekeeping force.

* BigGood: He's the only regional leader who's actively trying to fix things. [[spoiler:After Evolt is destroyed and for good and the world is remade as [[RetGone if he never influenced Earth in the first place]], Taizan is now the Prime Minister of Japan as a whole.]]

The secretary to Gentoku Himuro and another aide to the Prime Minister of Touto, Utsumi is rarely seen without his boss. After seemingly being killed by Gentoku as a substitute Night Rogue, he's saved by Stalk and recruited to work for Namba Heavy Industries. In this role, Utsumi develops Hokuto and Seito's Sclash Drivers, recreates the Kaiser System to create the Bros, and takes the original Transteam Gun for himself to become the second Night Rogue. He later uses the Evol Driver together with the Bat and Engine Fullbottles to become Kamen Rider Mad Rogue after being driven insane by Evolt.

* BigDamnHeroes: [[spoiler: Shows up when Gentoku is about to fight the Mimics Evolt generated of the Hell Bros, for what Gentoku thinks is making the fight 3-on-1. Then he promptly turns on the Hell Bro Mimics, at least entering an EnemyMine with Gentoku]].
* BodyBackupDrive: [[spoiler: The real reason Evolt gave him a copy of the Evol Driver was to make it so that he could use Utsumi as a host body in the event of his "death".]]

* BrainwashedAndCrazy: As a Namba Child he's been conditioned since childhood to be absolutely loyal to Namba himself. This works in Evolt's favor after he ''kills'' Namba, as Utsumi's unstable mental state causes him to snap and swear loyalty to Evolt instead.

* CrazyPrepared: [[spoiler: He designed Hell Bros with a deliberate weakness to the [=SameBike=] Best Match. He had no reason to ever think that Hell Bros would be used against him or Namba, but it pays off ''much'' later when he and Gentoku team up against a Mimic created by Evolt.]]

* CrouchingMoronHiddenBadass: After becoming Mad Rogue he spends most of his time either getting his ass kicked to show off new forms and power-ups or generally just a slightly more powerful enemy to fill out fights. [[spoiler: In the third-to-last episode he reveals that he was faking loyalty to gather data on Evolt's Phases to become even more powerful and avenge Namba. He actually keeps Evolt up against the ropes for a while before he gets too cocky and activates Phase 4, blowing out his own cybernetics.]]

* DespairEventHorizon: After Evolt kills Namba, Utsumi leaps over the edge, cracks a goofy grin and gleefully swears loyalty to Evolt, becoming Mad Rogue.

* TheDragon: After becoming Mad Rogue, he is effectively this to Evolt, acting as his enforcer and doing his dirty work whenever he doesn't feel like getting involved.
* DragonTheirFeet: While acting as Namba's assistant for a portion of the series, after Namba gets offed by Evolt, Utsumi goes on to serve him.

* FatalFlaw: His reliance on having superior weaponry and data. As Mad Rogue, he mainly relies on his Evol Driver boosting his capabilities. However, it's never enough to truly close the gap between him and the heroes since not only do they have higher Hazard Levels and/or equivalent technology, they also have much more combat experience than him. [[spoiler: In the end, his over reliance on the Evol Driver costs him dearly when he pushes his Evol Driver to Phase 4 in order to deal the finishing blow to Evolt only for the power to be too much for his cyborg body, interrupting him at the worst possible moment.]]
* {{Flanderization}}: [[spoiler:Utsumi's appearances in Build new world are mostly internet memes made AscendedCanon.]]
* FourEyesZeroSoul: Always seen wearing a pair of glasses, though he doesn't fully embrace the "Zero Soul" part until he [[SanitySlippage goes crazy]] and joins Evolt. [[spoiler:Somewhat subverted when it's revealed he was just biding his time until he could get revenge for Namba's death.]]
* ForcedToWatch: All he can do as Evolt kills Namba is helplessly watch over his tablet's live feed. This directly leads to his SanitySlippage and becoming Evolt's [[TheDragon Dragon.]]
* GoMadFromTheRevelation: The death of his "father figure" Juzaburo Namba in Episode 38 seems to drive him over the edge. Evolt shows up and throws him Namba's walking stick while asking him if he wants "Do you want revenge for Namba, or to swear your loyalty to me?" Utsumi [[FlashBack flashes back]] to memories of his time under Namba...and then [[LaughingMad bursts out laughing]], breaks the cane over his knee, and signs up with Evolt with a grin on his face. Appropriately enough, his new form is named Kamen Rider ''Mad'' Rogue. [[spoiler:It's later subverted when it's revealed that this was all an act just so he'd have a chance to avenge Namba]].
* GoodAllAlong: [[spoiler:Er, Less Evil All Along, but it's revealed in episode 47 that he was only pretending to be on Evolt's side, if only for the chance to gather data to use against Evolt to avenge Namba. He still holds a grudge against Gentoku for what happened earlier, but he's more than willing to put aside that grudge if it means the chance to take down Evolt]].

* HeroicSacrifice: [[spoiler:Sacrifices himself to protect Gentoku and Sawa against a blow from Evolt. However, he's only protecting the Lost Bottle, since he still hasn't entirely forgiven Gentoku]].

* IFightForTheStrongestSide: Utsumi has no real will on his own and usually falls in line with whoever is directly in charge at the time such as Gentoku, Namba, and ultimately Evolt.

* OnlySaneMan: With the obvious exclusion of Sawa who is the only one who got out the sinking ship that is Namba Heavy Industries. Utsumi seems to be the only villain to openly question Evolt's methods. It's then blown straight to hell once Utsumi joins Evolt and becomes the oh so fittingly named Mad Rogue.

** [[spoiler:In Build new world there is nothing left of Utsumi. And recovering his memories has reduced him from a loyal worker to a living {{meme}}of a man.]]
* SatelliteCharacter: The majority of his character revolves around his role as Gentoku's secretary, until his apparent death in episode 12 and his return in episode 18, at which point he switches to being Juzaburo Namba's satellite instead. Come episode 38, he's now ''Evolt's.''
* SpannerInTheWorks: [[spoiler: During TheMovie, he ends up breaking Gentoku and Kazumi out of Kengo's captivity, allowing them to help Sento. Unsurprisingly, he makes them beg for his help first]].

* TookALevelInBadass: He actually gets to ''fight'' as Night Rogue in the [=YouTube=] specials, showing himself to be a great deal more cunning and analytical than Gentoku ever was. He later gets an even bigger upgrade after receiving an Evol Driver (which explicitly needs a Hazard Level of 5) from Evolt to become Kamen Rider Mad Rogue.

The researcher originally in charge of studying the Pandora's Box, a brilliant man known as "The Devil's Scientist" by his colleagues. Ryuuga was arrested for his murder prior to the series, and discovering the mystery behind Katsuragi's murder is his main motivation.

* AntiHero: Once his full motivations are revealed, it's clear that Katsuragi was seeking a good end, but for vengeance rather than justice. Unlike his current personality as Sento, Katsuragi is willing to get his hands dirty in order to defeat the likes of Kaisei Mogami and Evolt, even as far as to steal Ex-Aid's powers or try to kill the yet-to-be awakened Ryuga just to achieve his goals, but that same willingness to do anything to kill Evolt was what let the snake take advantage of Katsuragi's brilliance to help get his plans rolling.
* BackFromTheDead: Either as a side-effect of his possession or as a deliberate act of spite, Evolt's theft of Sento's body causes Takumi's memories and personality to return and Sento's to vanish. It only lasts for a few episodes before Takumi willingly "dies" a second time.

** Relationships: Sento, despite his smug behavior, has complete trust in his allies, cares for Misora as a clear friend, and despite bickering with Ryuga several times, they are clearly best friends. On the other side, Takumi trusts nobody, sees Misora as nothing but a means to create [=FullBottles=], and was actively ''trying'' to kill Ryuga due to the latter containing Evolt's [=DNA=].

** And finally, their beliefs. Sento wanted to use the Build system as a way to ''protect'' people, and believed that science should be used to help instead of destroying. Takumi wanted to use the Build system to defeat Evolt, which turns into a plot point when he could not use the Genius [=FullBottle=] as his desire was not compatible with Sento's sense of justice.
* GoodIsNotNice: When his memories return late in the series, his primary goal is to defeat Evolt to save humanity. However, he dismisses anyone of "lesser" intelligence, treating Sento's friends and allies as little more than gibbering chimps and refusing to hear any debate about sparing Banjou's life because they can't offer it in a logical manner.
* HeelFaceDoorSlam: Played with. He attempted to quit Faust and kill both Blood Stalk and Banjou upon discovering that they were the mind and body of Evolt, only for Stalk to have outplayed him by swapping Katsuragi's Build Driver for the nonfunctional prototype. Stalk then wiped Katsuragi's memory and changed his appearance, turning him into Sento. He still ended up becoming a good guy, but in a way that, initially, served Stalk's plans rather than ruining them.
* HesBack: In the absolute worst way. Raising his Hazard Level into the ''[[BeyondTheImpossible 6.0 range]]'' and subsequently being possessed by Evolt restored his memories at the cost of Sento's personality disappearing.

* MyGodWhatHaveIDone: After his return, he dissolves his relationship with Gentoku once he learns that in spite of all they had sacrificed to create the Rider System, the nightmare scenarios they tried to prevent with its usage (Evolt's return to power and a Japanese civil war respectively) still came to pass.

* StrawVulcan: During his return in Episodes 37-39, he dispassionately dismisses the rest of the cast's silly antics and belief in friendship as nonsense straight out of a shonen manga while planning out a way to destroy Evolt...and Banjou, whom he believes will become another Evolt if left unchecked. However, despite having created the Genius Bottle himself, he's unable to use it because he doesn't have the right emotional mindset; after he regains all his memories and becomes the emotional Sento Kiryu again, the Genius Bottle works perfectly, creating [[SuperMode Build Genius Form]].

* WellIntentionedExtremist: Katsuragi is implied to have had sympathetic motivations for creating Faust, but the monster he created grew far beyond his control. When he learned who Evolt was, he tried to kill him and his other host Banjou before he could set into motion his plan to destroy the world.

In truth, before his supposed death, Shinobu was blackmailed by the newly-arrived Evolt into fixing the broken Evol Driver, and his research notes on Evolt, the Evol Driver, and the Pandora Box prove crucial to the creation of the Genius [=FullBottle=]. ''Supposed'' death, because evidence soon comes to light that like his son, rumors of Shinobu's death have been greatly exaggerated.

* AlwaysSomeoneBetter: He's this to Takumi and Sento, being able to not only repair the Evol Driver, but create a replacement [=EvolBottle=] for the one that broke on Mars, and even constructed a whole new Evol Driver almost as good as the original, though tuned down for a human. While the Genius [=FullBottle=] is made using Takumi's skills and Sento's purifier machine, it's built on a function of the Pandora Box that Shinobu discovered. He also created the [[PsychoPrototype Lost Bottles]], although even Takumi can't begin to fathom why his father would have done something so vile. It's eventually revealed that they exist for a project similar to what Takumi had previously explored with Kaisei Mogami: to eliminate Evolt and undo his actions by creating a MergedReality, using Evolt himself as the fuel source.

* AmbiguouslyEvil: Shinobu's actions at first appear unquestionably evil, but soon contain enough shades of stealth mentoring Sento that it's clear there's more to Shinobu than meets the eye. He disables Build by striking the Hazard Trigger, then uses [=NinninComic=]'s SmokeOut ability to teleport Sento to safety, all while delivering a speech that can be read as either EvilGloating or a legitimate warning. Sento later realizes that he can use the same trick on the Evol Trigger and starts wondering if his father showed him the trick on purpose so he could use it against Evolt.
* BigGood: Shinobu eventually turns out to be a secondary one after it's revealed that he's GoodAllAlong. While Vernage gave the heroes a fighting chance, it's Shinobu's actions that ultimately paved the way for Evolt's defeat. After making contact with Evolt, he elected to feign allegiance with him in order to study both him and the Pandora Box. Not only did this allow him to create the Rider System, but it also allowed him to learn of the Black and White Pandora Box Panels, allowing him to trick Evolt into sparing Earth for the time being with the promise of more power, and create a means by which Evolt could be destroyed and everything he did would be undone. While he never lived long enough to see the plan to through the end, he was able to entrust the plan to Sento, who was ultimately able to finish the job.
* EvilCounterpart: While not truly evil, Shinobu plays the role while being active on Evolt's side as another Kamen Rider Build.
* GoodAllAlong: As it turns out, he's been plotting against Evolt the entire time just waiting for his chance. Once Evolt's defeated by the other Riders he seals the Evol Driver in a canister to keep him from regenerating and reveals his plan to use the black Pandora Panel to do something to protect humanity. Unfortunately, Evolt had a backup plan and Shinobu is KilledOffForReal in retribution for his betrayal.

* IDidWhatIHadToDo: He worked with Evolt even though his plans would kill a whole lot of innocent people because if Evolt won, it would mean that ''everyone'' would die. Thus, he stuck close to Evolt in order to plot against him right under his nose.

* OutGambitted: He planned to trick Evolt into losing on purpose in order to complete the last Lost Bottles and then trap his Evol Driver inside a canister in order to prevent him from regenerating, and then use the Black Pandora Panel's warp travel abilities to hopefully find a more permanent solution. Unfortunately, Evolt was already suspicous of Shinobu and was smart enough to splinter off a part of himself to posses Utsumi, allowing him to confirm his suspicions, retrieve his Driver and claim the Lost Bottles and Black Pandora Panel.

[[/folder]]

----

!!!Tropes exclusive to him as Kamen Rider Mad Rogue:

* BecauseYouWereNiceToMe: It's implied in the [=YouTube=] specials that he has a soft spot for Sento because the latter sees him as a fellow scientist, rather than just the weapons factory that Namba and Night Rogue treat him as. [[RealityEnsues However,]] this does nothing to stop his loyalties to Namba Industries or prevent him from using the data he gathered on Kamen Rider Build to perfect the Hell Bros.

* RealityEnsues: When he fights as Build in Episode 38, he can't handle the various upgrades, weapons and tweaks that Sento made in his "absence" as the furthest he got was ''[=GorillaMond=]''. He also didn't realize that the Pandora's Box panel doesn't work as a power-up because it's meant to simply increase the user's Hazard Level fast enough for them to perform a SuicideAttack.

* FamousLastWords: "Takumi... Have you gotten taller again?"

* AceCustom: Zig-Zagged. Utsumi's Evol Driver, while visually identical, had been modified and tuned for human use. While it gives him greater initial power compared to users of the Build System, it has a lower limit than Evolt's original.

!!Shinobu Katsuragi / Kamen Rider Build