History YMMV / KamenRiderBuild

** [[OmnicidalManiac Evolt]]/[[SatanicArchetype Kamen Rider Evol]], the true mastermind behind the problems faced by the heroes, is an entity seeking to create a "new world" by [[PlanetEater devouring everything in the universe]], leaving only himself. Destroying planets alongside his people, the [[PlanetLooters Blood Tribe]], Evolt wiped out many civilizations before being stopped on Mars by the surviving Martian Queen Vernage. Possessing an astronaut and rendering him [[AndIMustScream aware but unable to do anything]], Evolt goes to the Earth and causes the Skywall Disaster that killed countless innocents and split Japan into three states. Under the alias "Blood Stalk", Evolt corrupts Gentoku Himuro by preying on his mind and killing his best friend and founds [[Characters/KamenRiderBuildFaust Faust]] with him and scientist Takumi Katsuragi to carry out painful experiments on kidnapped people to turn them into [[MonsterOfTheWeek Smash]]. When Katsuragi discovers his alien origins and turns against him, Evolt mind wipes him, kills an innocent man to swap his face with him, and renames him "[[Characters/KamenRiderBuildSentoKiryu Sento Kiryu]]" so he can keep using him. Desiring Ryuga Banjo, whom he corrupted with his DNA when he was only an infant, as his new host, Evolt had Ryuga's fiancée, fatally transformed into a "Smash", to increase Ryuga's raise Hazard Level by increasing his rage. Inciting a war between the three states of Japan, Evolt painfully experiments on Gentoku to turn him into a weapon and takes over Sento's body, keeping his personality around so he can [[ForcedToWatch make him watch]] as he slaughters his friends. He later betrays Namba and challenges the Kamen Riders to a final battle where they will have to reach the top of the Pandora Tower, destroying a section of Japan for every ten minutes they don't make it. Achieving his ultimate form, Evolt summons a Black Hole to consume the Earth but destroys it slowly [[ForTheEvulz so he can gaze at the despair on the heroes' faces for longer]].

* TheyWastedAPerfectlyGoodCharacter: Soichi Isurugi. Starting as a loveable mentor figure to our main rider, Soichi being revealed as Blood Stalk added a rather interesting nuance and layers to his character. While he was a villain, Soichi still had some rather sympathetic aspects in him, such as him showing regrets of his actions and helping the heroes from time to time, even having a pep talk to Sento at the latters lowest point. Then come TheReveal where [[spoiler:it turns out that Soichi was used as a meatpuppet by an EldritchAbomination, pretty much turning a lot of aftermentioned nuance obsolite. Their dynamic isn't even explored, as Evolt ditches Soichi shortly after the reveal. The fact that Soichi spends rest of the series in a coma and doesn't even get to help the heroes in defeating Evolt doesn't help the matters either.]]
** There are also some fans who feel that Juzaburo Namba, as an influential businessman and NonActionBigBad who utilizes on manipulation and political maneuvering to further his goals, also made for an excellent main antagonist and would have preferred if [[spoiler:he had stayed in the show for longer rather than be usurped by Evolt.]]

** [[OmnicidalManiac Evolt]]/[[SatanicArchetype Kamen Rider Evol]], [[BigBad the true mastermind]] behind the problems faced by the heroes, is an entity seeking to create a "new world" by [[PlanetEater devouring everything in the universe]], leaving only himself. Destroying planets alongside his people, the [[PlanetLooters Blood Tribe]], Evolt wiped out many civilizations before being stopped on Mars by the surviving Martian Queen Vernage. Possessing an astronaut and rendering him [[AndIMustScream aware but unable to do anything]], Evolt goes to the Earth and causes the Skywall Disaster that killed countless innocents and split Japan into three states. Under the alias "Blood Stalk", Evolt corrupts Gentoku Himuro by preying on his mind and killing his best friend and founds [[Characters/KamenRiderBuildFaust Faust]] with him and scientist Takumi Katsuragi to carry out painful experiments on kidnapped people to turn them into [[MonsterOfTheWeek Smash]]. When Katsuragi discovers his alien origins and turns against him, Evolt mind wipes him, kills an innocent man to swap his face with him, and renames him "Sento Kiryu" so he can keep using him. Desiring Ryuga Banjo, whom he corrupted with his DNA when he was only an infant, as his new host, Evolt had Ryuga's fiancée, fatally transformed into a "Smash", to increase Ryuga's raise Hazard Level by increasing his rage. Inciting a war between the three states of Japan, Evolt painfully experiments on Gentoku to turn him into a weapon and takes over Sento's body, keeping his personality around so he can [[ForcedToWatch make him watch]] as he slaughters his friends. He later betrays Namba and challenges the Kamen Riders to a final battle where they will have to reach the top of the Pandora Tower, destroying a section of Japan for every ten minutes they don't make it. Achieving his ultimate form, Evolt summons a Black Hole to consume the Earth but destroys it slowly [[ForTheEvulz so he can gaze at the despair on the heroes' faces for longer]].

** For the most part Gentoku is a well liked character. What causes discourse however, is his behavior post HeelFaceTurn. Did the show turning him from an interesting AntiVillain into a comic relief character ruin him, or was it just a way to show a different perspective. To be fair, the shift in his behavior has both an explanation both in universe and [[RealLifeWritesThePlot out of it]].

* WhatAnIdiot: [[WhatAnIdiot/KamenRider See here]].

* AlternateCharacterInterpretation: [[spoiler:In the V Cinema, Evolto suddenly decides that destroying Earth isn't worth the effort anymore, despite the people of the planet directly insulting him and defeating him, and after helping to butcher the only family he has in the universe, he just says ''Ciao'' and goes into the wild blue yonder. And all through the movie he's unusually determined to assist Banjo. This raises the possibility that he's developed empathy as a result of gaining human emotions, and he's just too proud to admit any sort of weakness on his own part, nor any emotional attachment to his spawn.]]

** Evolto. While he is one of the franchise's most popular villains due to his charismatic personality and devious plans, others see him as too cunning and overpowered, and that his constant outsmarting of the cast makes the show feel predictable and padded out at times. There is also discourse of the way he is written in the second half: Was he better when we knew him as Blood Stalk and did knowing his true identity make his character worse? Did his reveal of being a cosmic horror ruin the second half of the show? The world may never know.

* CatharsisFactor: ''Any'' time things don't go [[spoiler:Evolto's]] way and he gets royally ticked off is this, given how incredibly smug he is.

* EsotericHappyEnding: The end of Kamen Rider Cross-Z NEW WORLD: [[spoiler:Killbus is dead! Universe destruction averted! And Evolto decides to leave Earth while promising to return when he has full power with his form that let him destroy entire planets in an instant… Yay? Of course, that all depends on if you think his time with Ryuga taught him empathy or not]].

** [[SnakesAreSinister Blood Stalk]] has the same cool factor as Night Rogue, but with a [[FauxAffablyEvil fun personality]] and [[RedAndBlackAndEvilAllOver more color]]. Taken even further by his upgrade into [[spoiler:Kamen Rider Evol]]. You thought the other evil riders and pseudo riders in ''Build'' were walking swag factories of puppy kicking hate and balls blasting epic. In comes [[spoiler:Evolto]] who pretty much exists to exclaim the virtues that evil gets all the cool toys.

** The classical music piece played at the start of #29 is "An die Freude", from the final movement of [[Music/LudwigVanBeethoven Beethoven]]'s Ninth Symphony, and one of his most famous works. [[spoiler:Evolto's]] Standby music for his regular forms is a twisted techno version of that piece.
** The standby music for [[spoiler:Evolto's Black Hole Form]] is a twisted version of "O Fortuna" by Carl Orff.
** In Episode 38, Namba is sitting in his office listening to a woman play Frédéric Chopin's "Revolutionary Etude" on the piano. [[spoiler:Not only does Evolto's newly-achieved Black Hole Form get announced with the phrase "Revolution!", but that very same episode he finally drops the subservient act and "revolts" against Namba by killing him.]]

** [[spoiler:The "Fragile" warning on the back of Kamen Rider Rogue's helmet initially seemed like a cute FreezeFrameBonus… then came Episode 48, where Evolto breaks the helmet shortly before killing Gentoku]] It can be argued this happens even sooner, if you consider the reveal that [[spoiler:the suit contains a ''thoroughly'' broken man who endured grueling physical torture to try and keep up in the Kamen Rider arms race.]]

*** [[spoiler:This becomes even more brilliant on the reveal as to why he makes crappy coffee. Soichi may have known how to make coffee, but Evolto certainly doesn't]].

** Tetsuo Kanao (Evolto's voice actor) actually performed the voice of [[spoiler:another PlanetEater in a film a few months before ''Build'' premiered, being the voice of Ego, the Living Planet in ''Film/GuardiansOfTheGalaxyVol2'']].

** Fanfiction of Sento and Ryuga was up before the show even aired. The show itself calls them a "Best Match" in the title of the first episode, and their relationship is central to the story. Sento outright says that he and Ryuga are a best match [[spoiler:in the series finale, before defeating Evolto]].

** The finale has one that manages to completely [[UpToEleven outdo EVERYTHING that came before it and then some]], courtesy of the title character himself. How does he achieve such a feat? [[spoiler:By delivering a Rider Kick so utterly powerful and devastating that it not only [[RetGone erases Evolto's very existence]], but the attack itself '''[[BeyondTheImpossible can be seen all the way into space and between the two worlds]]''']].

* TheyWastedAPerfectlyGoodCharacter: Soichi Isurugi. Starting as a loveable mentor figure to our main rider, Soichi being revealed as Blood Stalk added a rather interesting nuance and layers to his character. While he was a villain, Soichi still had some rather sympathetic aspects in him, such as him showing regrets of his actions and helping the heroes from time to time, even having a pep talk to Sento at the latters lowest point. Then come TheReveal where [[spoiler:it turns out that Soichi was used as a meatpuppet by an EldritchAbomination, pretty much turning a lot of aftermentioned nuance obsolite. Their dynamic isn't even explored, as Evolto ditches Soichi shortly after the reveal. The fact that Soichi spends rest of the series in a coma and doesn't even get to help the heroes in defeating Evolto doesn't help the matters either.]]

* SugarWiki/AwesomeMusic:
** The OP, [[https://www.youtube.com/watch?v=tH7NWi7mLOk "Be The One"]] is very catchy.
*** [[https://www.youtube.com/watch?v=G87WJDpNC8Y Now available officially in English!]]
** [[https://youtu.be/bHVcWNRgJ4M "Ready Go!"]], for Build's [[MidSeasonUpgrade RabbitRabbit and TankTank]] form.
** [[https://youtu.be/r3fq7cEJ41I "Burning My Soul"]] for Cross-Z [[SuperMode Magma]] form. The cover from Hiroyuki Takami (who previously did "Wish in the Dark" and "JUSTICE" from ''Series/KamenRiderExAid'') and [=AXL21=] is [[https://www.youtube.com/watch?v=ZmX0EdWB1QI no less awesome]]
** [[https://youtu.be/ZboeU_mPfPU "Evolution"]] for Evol's debut.
** [[https://youtu.be/kMdXDTF_mfM "Build Up"]] for Build's [[SuperMode Genius form]].
** [[https://youtu.be/62jYb7jOPBw "Law of the Victory"]] for the four main riders.
** [[https://youtu.be/uRSVDd22rlE "CROSS"]] from the V-Cinema of Cross-Z and for Cross-Z [[FusionDance Evol]] form.
** [[https://www.youtube.com/watch?v=pI2raO2diIQ "Perfect Triumph"]] from the V-Cinema of Grease which marks the end of Build's saga.

*** Even more so with the follow-up V-Cinemas restoring the cast’s memories. Was it a well-deserved EarnYourHappyEnding, or too much of a ResetButton to make the original ending seem like it mattered.

** Tetsuo Kanao (Evolt's voice actor) actually performed the voice of [[spoiler: another PlanetEater in a film a few months before ''Build'' premiered, being the voice of Ego, the Living Planet in ''Film/GuardiansOfTheGalaxyVol2'']].

** The reason why certain Full Bottles are Best Matches is revealed to be [[spoiler:what things (non-living) can destroy the things the Isurugis like (living)]]. It's nonsensical in different ways, [[spoiler:such as how [[NoKillLikeOverkill overkill]] some of the choices are when [[WhyDontYouJustShootHim just shooting them with a gun]] is more logical or that the later choices were deliberately nonsense choices made by Souichi]] and needless to say, people had a field day with joking about TheReveal.

* UnintentionallyUnsympathetic: Yui Mabuchi from Cross-Z's V-Cinema can come off as this. While Ryuga's past aversion to aiding civilians in favor of finishing fights is something to call out, some have noticed that the Guardians that captured her and her students allowing Faust to turn her into the first Scissors Lost Smash and her subsequent death only turned towards them when she ''[[ViolationOfCommonSense popped her head out of cover to shout at Cross-Z to come back and save her and her students.]]'' Her initial grudge against Ryuga long after his CharacterDevelopment also doesn't help.

* WhatAnIdiot:
** Ryuga's impulsiveness is usual source of this. Episode 6 presents the best example in his plan to uncover Faust's base. He followed Press Smash to the place and had not thought any further. Of course he was spotted and captured nearly immediately after arriving. If [[spoiler:Sento didn't appear]], things would be shitty for Ryuga.
*** Well, #6 is this for Ryuga pretty much from start to finish with attempts to get into Faust's base, transform or attack Blood Stalk.
*** He did it AGAIN in #15, ruining Sento's plan to get a recording of Night Rogue revealing himself.
*** And then again in #27 when his fighting spirit falters after he fell to Fu Washio's words of "his brother will get killed if he lose" thing, causing him to lose the match.
** Hokuto's Prime Minister Tajimi, of all the people, didn't escape the idiocy as well after she send all her troops to attack Touto thanks to Blood Stalk's suggestion, causing her homeland to be captured by Seito.
** Utsumi, having captured all of Kazumi's employees, has brought Gentoku[=/=]Kamen Rider Rogue along with him, in an attempt to get Kazumi to steal Pandora's Box, but Kazumi (wisely) decides not to take their bargain. Utsumi orders Gentoku to kill the hostages, but Gentoku refuses, setting them free. Gentoku has a special chip that will explode if his handlers get suspicious, and Utsumi reminds Gentoku of this. \\
'''You'd Expect''': For Utsumi to keep the remote triggering said chip in his pocket. No, really, that's all he had to do.\\
'''Instead''': Utsumi foolishly brings the remote out of his pocket, allowing Gentoku to knock it out of his hands. Clearly Utsumi took lessons from [[Anime/DragonBallZ Dr. Gero]] in this subject.
** Gentoku also suffers from this in the above situation; after knocking the remote out of Utsumi's hands:\\
'''You'd Expect''': Gentoku to immediately destroy--or at least grab--the remote.\\
'''Instead''': He ignores the remote, leaving Utsumi free to grab it and trigger the chip.
** Misora suffers this [[spoiler:after Gentoku knocks Evolto!Soichi out of his transformation. She is still holding the Evol Driver, but seeing her father]], she walks towards him.\\
'''You'd Expect''': Misora to put [[spoiler:the Evol Driver]] down or hand it off to someone else before approaching the one who not only covets said [[spoiler:Driver]], but has been antagonising the group for almost the whole show.\\
'''Instead:''' She keeps hold of [[spoiler: the Evol Driver]] as she approaches. Even if [[spoiler:Evolto wasn't going to attack her for the Driver]], [[spoiler:Utsumi takes her by surprise and throws the Evol Driver to Souichi]], allowing him to regain his true form.
** Namba himself seems to be an idiot that's TooDumbToLive, as even after Evolto almost started destroying Earth by opening Pandora's Box, he ''still thought they were on the same side.'' He also shows a spectacular amount of overconfidence when all he sends to kill Evolto when it's clear they're not working together is a contingent of Hard Guardians and the Kaisers when Evolto in his previous ''weaker'' forms had delivered consistent {{Curb Stomp Battle}}s to all four of the ''vastly stronger Kamen Riders'', both individually and in groups.

** Tetsuo Kanao (Evolt's voice actor) actually performed the voice of [[spoiler: another PlanetEater in a film earlier this year, being the voice of Ego, the Living Planet in ''Film/GuardiansOfTheGalaxyVol2'']].

* AlternateCharacterInterpretation: [[spoiler: In the V Cinema, Evolt suddenly decides that destroying Earth isn't worth the effort anymore, despite the people of the planet directly insulting him and defeating him, and after helping to butcher the only family he has in the universe, he just says ''Ciao'' and goes into the wild blue yonder. And all through the movie he's unusually determined to assist Banjou. This raises the possibility that he's developed empathy as a result of gaining human emotions, and he's just too proud to admit any sort of weakness on his own part, nor any emotional attachment to his spawn.]]

** Sento. Is he one of the better written main riders with an interesting arc that fits well to the show's central themes or is he an {{Jerkass}} with a poorly executed character arc? A lot of it has to do with AlternateCharacterInterpretation regarding the character, as there are different ways in reading in his actions throughout the show.
** Evolt. While he is one of the franchise's most popular villains due to his charismatic personality and devious plans, others see him as too cunning and overpowered, and that his constant outsmarting of the cast makes the show feel predictable and padded out at times. There is also discourse of the way he is written in the second half: Was he better when we knew him as Blood Stalk and did knowing his true identity make his character worse? Did his reveal of being a cosmic horror ruin the second half of the show? The world may never know.

* CatharsisFactor: ''Any'' time things don't go [[spoiler:Evolt's]] way and he gets royally ticked off is this, given how incredibly smug he is.

* EsotericHappyEnding: The end of Kamen Rider Cross-Z NEW WORLD: [[spoiler:Killbus is dead! Universe destruction averted! And Evolt decides to leave Earth while promising to return when he has full power with his form that let him destroy entire planets in an instant… Yay? Of course, that all depends on if you think his time with Ryuga taught him empathy or not]].

** [[SnakesAreSinister Blood Stalk]] has the same cool factor as Night Rogue, but with a [[FauxAffablyEvil fun personality]] and [[RedAndBlackAndEvilAllOver more color]]. Taken even further by his upgrade into [[spoiler:Kamen Rider Evol]]. You thought the other evil riders and pseudo riders in ''Build'' were walking swag factories of puppy kicking hate and balls blasting epic. In comes [[spoiler:Evolt]] who pretty much exists to exclaim the virtues that evil gets all the cool toys.

** The classical music piece played at the start of #29 is "An die Freude", from the final movement of [[Music/LudwigVanBeethoven Beethoven]]'s Ninth Symphony, and one of his most famous works. [[spoiler:Evolt's]] Standby music for his regular forms is a twisted techno version of that piece.
** The standby music for [[spoiler:Evolt's Black Hole Form]] is a twisted version of "O Fortuna" by Carl Orff.
** In Episode 38, Nanba is sitting in his office listening to a woman play Frédéric Chopin's "Revolutionary Etude" on the piano. [[spoiler:Not only does Evolt's newly-achieved Black Hole Form get announced with the phrase "Revolution!", but that very same episode he finally drops the subservient act and "revolts" against Nanba by killing him.]]

** Short range one in that everything nice/heartwarming/funny etc. [[spoiler: Souichi]] did prior to #13 is soured by the reveal of Blood Stalk's identity in #13.

** [[spoiler:The "Fragile" warning on the back of Kamen Rider Rogue's helmet initially seemed like a cute FreezeFrameBonus… then came Episode 48, where Evolt breaks the helmet shortly before killing Gentoku]] It can be argued this happens even sooner, if you consider the reveal that [[spoiler: the suit contains a ''thoroughly'' broken man who endured grueling physical torture to try and keep up in the Kamen Rider arms race.]]

** Souichi apparently went into the coffee shop business despite having no prior experience in making coffee [[spoiler:as an astronaut]], which really shows in the way the coffee turns out. Which is funny when you consider the number of times in Western media that [[spoiler:astronauts]] or people in that sort of space-age scifi environment can make their own coffee as a required skill, such as ''Film/EventHorizon'' or even ''{{VideoGame/Overwatch}}'' if you've seen "Rise and Shine".
*** [[spoiler:This becomes even more brilliant on the reveal as to why he makes crappy coffee. Souichi may have known how to make coffee, but Evolt certainly doesn't]].
** A short-range one where the whole scene with Ryuga holding the same DeathGlare consistently at Sento, now that he might be the real murderer, has been cited as resembling all the DevilInPlainSight shots of one [[Series/KamenRiderFaiz Masato Kusaka.]] Just two weeks later it's revealed that they already have a character like that. [[spoiler:It's Sawa]].
** Kamen Rider Cross-Z's looks and finisher are similar to Kamen Rider Ryuki and his PaletteSwap / EvilTwin, Ryuga. Guess who is Cross-Z? [[spoiler: Yup, it's [[NameIsTheSame Ryuga]].]]

** [[spoiler: In first part of ''ROGUE'', Gentoku compares Souichi to Mephistopheles (the faustian devil) and says he can't be as powerful. Then it turns out that Souichi really is not, but he is possesed by an EldritchAbomination that is the closent equivalent of the faustian devil ''Build'' has.]]

** The show set into a country being divided into three sections, each having tension with each other. The initial section of it is dedicated into fighting different minor threats/monsters, while trying to solve the mystery of the main characters enigmatic past and the world around them. Eventually the story escalates into all out war between the three divided sections as one of the villains, a masked figure with ties of a villanuous organization doing human experimentations [[spoiler:turns out to be one of the allies the entire time]]. [[spoiler: It's eventually revealed that everything in the story was more or less caused by a GreaterScopeVillain who were weakened as a result of a war with an otherworldly species which happened centuries before the story's beginning and resulted in near extinction of said species. And the protagonist is revealed to essentially share the body/conscience with a major character who tried to stop the villains but was murdered by them. The character in question ultimately fuses with the protagonist, giving them their ultimate form.]] [[VideoGame/FireEmblemThreeHouses Doesn't this sound rather familiar?]]

** Fanfiction of Sento and Ryuga was up before the show even aired. The show itself calls them a "Best Match" in the title of the first episode, and their relationship is central to the story. Sento outright says that he and Ryuga are a best match [[spoiler:in the series finale, before defeating Evolt]].

** A keen eye can notice that the [=TankTank=] suit's arms are being held together by [[https://imgur.com/a/J8fkC7G scotch tape in episode 44]], not unlike [[Series/KamenRiderOOO Ankh's arm]].

** In the ''New World: Cross-Z'' V Cinema, Kilbus darts between this and NightmareFuel at light speed. His flamenco dancer motions and habit of kissing his TransformationTrinkets, combined with his habit of [[CurbStompBattle trashing the heroes]] makes for a weird MoodWhiplash.

** Build manages to hit this as soon as #17 [[spoiler: with the war between Touto and Hokuto starting and the Kamen Riders being degraded from those two guys to weapons that should be at Gentoku's beck and call [[note]] At least that's what he expects. They [[IAmNotAGun disagree]]. [[/note]] ]].

** The finale has one that manages to completely [[UpToEleven outdo EVERYTHING that came before it and then some]], courtesy of the title character himself. How does he achieve such a feat? [[spoiler:By delivering a Rider Kick so utterly powerful and devastating that it not only [[RetGone erases Evolt's very existence]], but the attack itself '''[[BeyondTheImpossible can be seen all the way into space and between the two worlds]]''']].

** For reasons unclear, Night Rogue's stunt undersuit is an unsightly maroon color which clashes heavily with the black armor and looks decidedly different from the black undersuit during his debut episode. This might not be a problem if not for the stunt suit often being used in place of the original costume entirely from around episode 8 onwards. The same undersuit gets reused for Engine Bros, Remocon Bros, and Kamen Rider Mad Rogue, with the same glaring difference in color.

** In the V Cinema, Kilbus' Rider form has a spider theme, which means he can create webbing. This is all well and good until the cameras close in on the Riders, and the webbing goes from CGI to mediocre stringy ropes.

* TheyWastedAPerfectlyGoodCharacter: Souichi Isurugi. Starting as a loveable mentor figure to our main rider, Souichi being revealed as Blood Stark added a rather interesting nuance and layers to his character. While he was a villain, Souichi still had some rather sympathetic aspects in him, such as him showing regrets of his actions and helping the heroes from time to time, even having a pep talk to Sento at the latters lowest point. Then come TheReveal where [[spoiler: it turns out that Souochi was used as a meatpuppet by an EldritchAbomination, pretty much turning a lot of aftermentioned nuance obsolite. Their dynamic isn't even explored, as Evolt ditches Souichi shortly after the reveal. The fact that Souichi spends rest of the series in a coma and doesn't even get to help the heroes in defeating Evolt doesn't help the matters either.]]

** [[spoiler: [=RabbitDragon=] in the final episode is this, especially since it was a CGI model. Many pointed out they could have simply reused Cross-[=ZBuild=] from TheMovie]].

** Misora suffers this [[spoiler:after Gentoku knocks Souichi out of his transformation. She is still holding the Evol Driver, but seeing her father]], she walks towards him.\\

'''Instead:''' She keeps hold of [[spoiler: the Evol Driver]] as she approaches. Even if [[spoiler:Souichi wasn't going to attack her for the Driver]], [[spoiler:Utsugi takes her by surprise and throws the Evol Driver to Souichi]], allowing him to regain his true form.
** Nanba himself seems to be an idiot that's TooDumbToLive, as even after Evolt almost started destroying Earth by opening Pandora's Box, he ''still thought they were on the same side.'' He also shows a spectacular amount of overconfidence when all he sends to kill Evolt when it's clear they're not working together is a contingent of Hard Guardians and the Kaisers when Evolt in his previous ''weaker'' forms had delivered consistent {{Curb Stomp Battle}}s to all four of the ''vastly stronger Kamen Riders'', both individually and in groups.

* WinBackTheCrowd: WordOfGod says that one of the goals of the series is to bring back the demographic that had been turned off by how different ''Franchise/KamenRider'' has been for the past few years, with ''Build'' containing elements similar to the classic Shōwa ''Kamen Rider'' series.

* MemeticMutation:
** The motion for using the bottles to transform by shaking them has garnered hilarious usage, especially Sento angrily shaking two bottles before transforming in episode 6.
** Once [=NinninComic=] was revealed, the inevitable ''Manga/{{Naruto}}'' jokes spread like wildfire.
*** The fact that one of the first attacks Build uses is a [[DoppelgangerAttack duplication ability (literally "Bunshin no Jutsu")]] helped as well.
** This too is all Stalk's fault. [[labelnote: Explanation]] It seems that the further the series goes along, Stalk just gets more and more integrated into the main plot, to the point of becoming [[spoiler: the BigBad.]] [[/labelnote]]
** "Just punch harder, Banjou." [[labelnote: Explanation]] Fans joked about this constantly due to Ryuga somehow managing to resort to pure brute force when all other methods are exhausted. [[/labelnote]]
** [[PowerUpLetdown His power up is another weapon]].[[labelnote: Explanation]]Grease is able to put the Dragon Sclashjelly in his driver to access...another Twin Breaker. Fans then mocked how basically just giving Grease two of the exact same weapon was treated as some power up and how poor Grease seemed to get the short end of the stick. Becomes more or less a DiscreditedMeme with the introduction of Grease Blizzard at the end of the series and Perfect Kingdom in his V-Cinema.[[/labelnote]]
** The infamous scene where Utsumi [[spoiler:going insane and snapping Namba's cane in half]] in episode 38 led to a fair share of memes. [[https://twitter.com/mao_mao514/status/1003108379433172993 Case in point]].
** Sento's raging [[SayMyName reaction]][[note]]'''EVOLT!!!'''[[/note]] to Evolt casually greeting the team with a "Yo!" to twist in the knife while they're [[spoiler: mourning Kazumi]] has been photoshopped with various degrees of glowing/flaming eyes and has been used as a common reaction image.
** "[[SupermanStaysOutOfGotham Fourze, you lying sack of shit]]." [[labelnote: Explanation]]At the end of Heisei Generations Final, [[Series/KamenRiderFourze Gentaro]] says that they'll rush to each other's aid in times of trouble to Sento. While obviously it wouldn't take, fans still poked fun at this by having a IronicEchoCut to Evolt putting Build's world in jeopradoy, to which the edited in captions read out as the meme.[[/labelnote]]
** Much like the "''Series/KamenRiderGaim'' belongs on HBO" confession, the "I personally think that Build is the only show that could be aired in the West" confession has gotten some traction being rather absurd, but also for coming from ''the same confessions page as well''.

* MagnificentBastard: [[spoiler:[[BigGood Shinobu Katsuragi]]/[[SuperPrototype Kamen Rider Build (Prototype)]] is the father of hero Sento Kiryu aka Takumi Katsuragi and the progenitor of Project Build. Following the Sky Wall Disaster, Shinobu successfully fakes his death after being blackmailed by [[BigBad Evolt]], working with the sinister alien while [[TheStarscream secretly taking steps to stand against him and his universe destroying plans]] for a whole decade. Soon after Sento obtains his SuperMode, Shinobu reveals himself alive and his alliance with Evolt to Sento and his allies, using this as the opportunity to play StealthMentor in order to raise the Hazard Levels for his son and [[TheLancer Banjo Ryuga]] for his own ends. After being found out and killed by Evolt, Shinobu uses his last moments to pass on important information to his son, giving Sento the tools he needs to execute his true plan in his place: merging parallel worlds by using Evolt himself as a LivingBattery, effectively deleting the evil alien from time and reality. Fully determined to atone for his role in all of the tragedy that occurred in the series, Shinobu's actions led to the world of love and peace he and his son became scientists to create]].

* TheyWastedAPerfectlyGoodCharacter: Souichi Isurugi. Starting as a loveable mentor figure to our main rider, Souichi being revealed as Blood Stark added a rather interesting nuance and layers to his character. While he was a villain, Souichi still had some rather sympathetic aspects in him, such as him showing regrets of his actions and helping the heroes from time to time, even having a pep talk to Sento at the latters lowest point. Then come TheReveal where [[spoiler: it turns out that Souochi was used as a meatpuppet by an EldritchAbomination, pretty much turning a lot of aftermentioned nuance obsolte. Their dynamic isn't even explored, as Evolt ditches Souichi shortly after the reveal. The fact that Souichi spends rest of the series in a coma and doesn't even get to help the heroes in defeating Evolt doesn't help the matters either.]]
* TheyWastedAPerfectlyGoodPlot: Wow, Sento can use the Hazard Trigger to make a more powerful version of any of his other forms? Too bad we never see [[spoiler:[=RabbitTank=] Sparkling Hazard]], although it's possible that Sento might consider said form TooAwesomeToUse due to how out of control most of his other forms are when using the Hazard Trigger.

* MagnificentBastard: [[spoiler: [[BigGood Shinobu Katsuragi]]/[[SuperPrototype Kamen Rider Build (Prototype)]] is the father of TheHero Sento Kiryu aka Takumi Katsuragi and the progenitor of Project Build. Following the Sky Wall Disaster, Shinobu successfully fakes his death after being blackmailed by [[BigBad Evolt]], working with the sinister alien while [[TheStarscream secretly taking steps to stand against him and his universe destroying plans]] for a whole decade. Soon after Sento obtains his SuperMode, Shinobu reveals himself alive and his alliance with Evolt to Sento and his allies, using this as the opportunity to play StealthMentor in order to raise the Hazard Levels of his son and [[TheLancer Banjo Ryuga]] for his own ends. When found out and fatally wounded by Evolt, Shinobu uses his last moments to pass on important information to his son, giving Sento the tools he needs to execute his true plan in his place: merging parallel worlds by using Evolt himself as a LivingBattery, effectively deleting the evil alien from time and reality. Fully determined to atone for his role in all of the tragedy that occurred in the series, Shinobu's actions led to the world of love and peace he and his son became scientists to create.]]

* MagnificentBastard: [[spoiler: [[BigGood Shinobu Katsuragi]]/[[SuperPrototype Kamen Rider Build (Prototype)]] is the father of TheHero Sento Kiryu aka Takumi Katsuragi and the progenitor of Project Build. Following the Sky Wall Disaster, Shinobu successfully fakes his death after being blackmailed by [[BigBad Evolt]], working with the sinister alien while [[TheStarscream secretly taking steps to stand against him and his universe destroying plans]] for a whole decade. Soon after Sento obtains his SuperMode, Shinobu reveals himself alive and his alliance with Evolt to Sento and his allies, using this as the opportunity to play StealthMentor in order to raise the Hazard Levels of his son and [[TheLancer Banjo Ryuga]] for his own ends. After being found out and killed by Evolt, Shinobu uses his last moments to pass on important information to his son, giving Sento the tools he needs to execute his true plan in his place: merging parallel worlds by using Evolt himself as a LivingBattery, effectively deleting the evil alien from time and reality. Fully determined to atone for his role in all of the tragedy that occurred in the series, Shinobu's actions led to the world of love and peace he and his son became scientists to create.]]

* MagnificentBastard: [[spoiler: [[BigGood Shinobu Katsuragi]]/[[SuperPrototype Kamen Rider Build (Prototype)]] is the father of TheHero Sento Kiryu aka Takumi Katsuragi and the progenitor of Project Build. Following the Sky Wall Disaster, Shinobu successfully fakes his death after being blackmailed by [[BigBad Evolt]], working with the sinister alien while [[TheStarscream secretly taking steps to stand against him and his universe destroying plans]] for a whole decade. Soon after Sento obtains his SuperMode, Shinobu reveals himself alive and his alliance with Evolt to Sento and his allies, using this as the opportunity to play StealthMentor in order to raise the Hazard Levels for his son and [[TheLancer Banjo Ryuga]] for his own ends. After being found out and killed by Evolt, Shinobu uses his last moments to pass on important information to his son, giving Sento the tools he needs to execute his true plan in his place: merging parallel worlds by using Evolt himself as a LivingBattery, effectively deleting the evil alien from time and reality. Fully determined to atone for his role in all of the tragedy that occurred in the series, Shinobu's actions led to the world of love and peace he and his son became scientists to create.]]

* MagnificentBastard: [[spoiler: [[BigGood Shinobu Katsuragi]]/[[SuperPrototype Kamen Rider Build (Prototype)]] is the father of hero Sento Kiryu aka Takumi Katsuragi and the progenitor of Project Build. Following the Sky Wall Disaster, Shinobu successfully fakes his death after being blackmailed by [[BigBad Evolt]], working with the sinister alien while [[TheStarscream secretly taking steps to stand against him and his universe destroying plans]] for a whole decade. Soon after Sento obtains his SuperMode, Shinobu reveals himself alive and his alliance with Evolt to Sento and his allies, using this as the opportunity to play StealthMentor in order to raise the Hazard Levels for his son and [[TheLancer Banjo Ryuga]] for his own ends. After being found out and killed by Evolt, Shinobu uses his last moments to pass on important information to his son, giving Sento the tools he needs to execute his true plan in his place: merging parallel worlds by using Evolt himself as a LivingBattery, effectively deleting the evil alien from time and reality. Fully determined to atone for his role in all of the tragedy that occurred in the series, Shinobu's actions led to the world of love and peace he and his son became scientists to create.]]

* ''[[Series/KamenRiderBuild Build]]'': [[spoiler: [[BigGood Shinobu Katsuragi]]/[[SuperPrototype Kamen Rider Build (Prototype)]] is the father of hero Sento Kiryu aka Takumi Katsuragi and the progenitor of Project Build. Following the Sky Wall Disaster, Shinobu successfully fakes his death after being blackmailed by [[BigBad Evolt]], working with the sinister alien while [[TheStarscream secretly taking steps to stand against him and his universe destroying plans]] for a whole decade. Soon after Sento obtains his SuperMode, Shinobu reveals himself alive and his alliance with Evolt to Sento and his allies, using this as the opportunity to play StealthMentor in order to raise the Hazard Levels for his son and [[TheLancer Banjo Ryuga]] for his own ends. After being found out and killed by Evolt, Shinobu uses his last moments to pass on important information to his son, giving Sento the tools he needs to execute his true plan in his place: merging parallel worlds by using Evolt himself as a LivingBattery, effectively deleting the evil alien from time and reality. Fully determined to atone for his role in all of the tragedy that occurred in the series, Shinobu's actions led to the world of love and peace he and his son became scientists to create.]]

** The show set into a country being divided into three sections, each having tension with each other. The initial section of it is dedicated into fighting different minor threats/monsters, while trying to solve the mystery of the main characters enigmatic past. Eventually the story escalates into all out war between the three divided countries as one of the villains, a masked figure, [[spoiler:turns out to be one of the allies the entire time]]. [[spoiler: It's soon revealed that this was more or less caused by a GreaterScopeVillain who was behind most if not all of the story's major events whether directly or indirectly. And the protagonist is related to essentially share the body/conscience with a major character who tried to stop and was murdered by said greater scope villain before they ultimately fuse with them.]] [[VideoGame/FireEmblemThreeHouses Doesn't this sound rather familiar?]]

** [[spoiler:The "Fragile" warning on the back of Kamen Rider Rogue's helmet initially seemed like a cute FreezeFrameBonus… then came Episode 48, where Evolt breaks the helmet shortly before killing Gentoku]].