History Trivia / KamenRiderZiO

* NamesTheSame:
** The MonstersOfTheWeek for this series are "Another Riders", distorted and monster-fied versions of Kamen Riders. ''Series/KamenRiderAgito'' already used both the name and the concept with Another Agito, a person who had the potential to become Agito but instead assumed a monster-like form because only one "true" Agito can exist at any given time. Predictably, this caused problems for the staff, who ultimately opted to use the existing Another Agito suit as ''Agito''[='s=] Another Rider, albeit with relevant modifications.
*** Zi-O also has a form called "Trinity", the same name as one of Agito's. This comes full circle when their teamup features both of them using their Trinity Forms together.
** Also, the name of the series has been compared to the names of ''Series/PowerRangersZeo'' and ''Film/KamenRiderZO,'' with every joke you'd expect to be made about it.
** Kamen Rider Ginga has the name of another [[Series/UltramanGinga galaxy-theme warrior from an another franchise.]] Incidentally an MilestoneCelebration where the hero transforms into other Ultramen. And more hilariously [[Creator/TomokazuSugita both shares the same voice actor.]]
** The non-canon Another Rider (speaking rather loosely) who weaponizes OriginalGeneration, named King, is not to be confused with [[Series/KamenRiderBlade the Caucasus Undead]] or [[Series/KamenRiderKiva the first Dark Kiva]].

** In a similar case to Ankh from ''OOO'', Woz was originally intended to become the BigBad at the end, but his chemistry with the rest of the heroic cast and popularity with the audience led to him remaining a TokenEvilTeammate throughout the series, never making a full FaceHeelTurn.

* McLeaned: The ultimate fate of [[spoiler:Tsukasa Kadoya]] in ''Zi-O vs. Decade'', being the last production related to the franchise that [[spoiler:Masahiro Inoue]] intends to star in.

** So Okuno pulls triple duty as Prime Sougo, Sougo from 3 days in the Future ("Gaim Arc"), and Dark Sougo ("Ryuki Arc"). ''Zi-O vs. Decade'' takes it UpToEleven by having him portray the prime Sougo and ''six'' alternate versions of him (Including one in ''Decade vs. Zi-O''), all with separate personalities.

** The MonstersOfTheWeek for this series are "Another Riders", distorted and monster-fied versions of Kamen Riders. ''Series/KamenRiderAgito'' already used both the name and the concept with Another Agito, a person who had the potential to become Agito but instead assumed a monster-like form because only one "true" Agito can exist at any given time. ''Zi-O''[='s=] staff are reportedly trying to figure out how to handle this, and have suggested that they might just use the existing Another Agito suit as ''Agito''[='s=] Another Rider, in which they ultimately did, albeit with relevant modifications.

*** The mooks he fights against are the Dustards from [[Series/KamenRiderFourze]].

*** The mooks he fights against are the Dustards from ''[[Series/KamenRiderFourze]]''.

*** The mooks he fights against are the Dustards from ''Series/KamenRiderFourze''.

*** Kamen Rider Ginga’s helmet is retooled from [[Series/KamenRiderWizard Kamen Rider Mage's]] helmet and costume is a modified version of Kamen Rider Fourze Meteor Fusion States with Meteor's regular legs and feet.

* FanNickname:
** Another Riders - Bizarro Riders[[labelnote:Explanation]]Due to fans likening them to ComicBook/{{Superman}}'s EvilKnockoff Bizarro, and possibly to avoid any confusion with Another Agito.[[/labelnote]], [[Series/KamenRiderDecade Kaijin Riders]][[labelnote:Explanation]]As a reference to [[Series/SamuraiSentaiShinkenger Chinomanako]], who was called an "Ayakashi Rider"; he also used cards to summon previous Rider monsters, labeled as "[=KaijinRide=]" cards.[[/labelnote]]
** Sougo/Zi-O - [[Series/KamenRiderDecade Destroyer of Catchphrases/Finishers]][[labelnote:Explanation]]Due to the fact that Zi-O completely butchers Build and Ex-Aid's catchphrase and finishers with an abridged version of his own.[[/labelnote]], 我が魔王~/"Waga Maō~"[[labelnote:Explanation]]Literally "My Demon King", and Woz's [[LargeHam over-the-top way]] of addressing Sougo.[[/labelnote]]
** The new Woz suffered from this heavily to differentiate him from the original Woz, having been given names such as "New Woz" or "Another Woz"[[note]]initally used by the Wiki[[/note]]. Eventually the official name stated on the TV-Asahi website is the InSeriesNickname "White Woz", while Woz himself is renamed as "Black Woz".
** Geiz - 我が救世主~/"Waga Kyūseishu~"[[labelnote:Explanation]]Literally "My Savior"; White Woz's equally over-the-top way of addressing Geiz, after the reveal of an alternate future created by Geiz Revive defeating Oma Zi-O.[[/labelnote]]
** Another AgitΩ: At least on this very wiki, because Another Agito already existed in Agito's original series, and Another AgitΩ himself has the omega symbol (Ω) instead of an 'o' on the chest plate, he's called this in order to differentiate the two.

* CashCowFranchise: The Ridewatches have a lineup that, when including giveaways, limited items, and other obscure sources, numbers at approximately ''246'' unique watches. This includes all upgraded and final forms for every phase 2 Heisei Rider (barring [[Series/KamenRiderExAid Brave Level 50]], but including [[Theatre/KamenRiderZangetsuGaimGaiden Zangetsu Kachidoki Arms]]), every final form for every primary phase 1 Heisei Rider and some forms/watches for the other Riders, and even some hypothetical or ''SIC Hero Saga''-exclusive forms like [[Series/KamenRiderDouble CycloneAccelExtreme]] and [[Series/KamenRiderRyuki Ouja Survive]]. All without ''any'' indication that they'd ever be used in the show or related material, and even ignoring that the super form Ridewatches are [[DepartmentOfRedundancyDepartment redundant]] to the Decade Ridewatch's functions. Bandai even tried to go even further by including basic alternate forms as part of the lineup, before being rejected in polls. Even after ''Zi-O'' had finished airing, they even made more with the [[Series/KamenRiderSaber Saber]] and Decade Complete Form 21 Ridewatches, and continue to release even more Ridewatches, with the Quartzer Ridewatches seeing a release in 2022. By the time ''Zi-O'' had finished airing, it had made ''30.2 Billion Yen,'' the most ever made for a ''Kamen Rider'' season.

* CashCowFranchise: The Ridewatches have a lineup that, when including giveaways, limited items, and other obscure sources, numbers at approximately ''246'' unique watches. This includes all upgraded and final forms for every phase 2 Heisei Rider (barring [[Series/KamenRiderExAid Brave Level 50]], but including [[Theatre/KamenRiderZangetsuGaimGaiden Zangetsu Kachidoki Arms]]), every final form for every primary phase 1 Heisei Rider and some forms/watches for the other Riders, and even some hypothetical or ''SIC Hero Saga''-exclusive forms like [[Series/KamenRiderDouble CycloneAccelExtreme]] and [[Series/KamenRiderRyuki Ouja Survive]]. All without ''any'' indication that they'd ever be used in the show or related material, and even ignoring that the super form Ridewatches are [[DepartmentOfRedundancyDepartment redundant]] to the Decade Ridewatch's functions. Bandai even tried to go even further by including basic alternate forms as part of the lineup, before being rejected in polls. Even after ''Zi-O'' had finished airing, they even made more with the [[Series/KamenRiderSaber Saber]] and Decade Complete Form 21 Ridewatches. By the time ''Zi-O'' had finished airing, it had made ''30.2 Billion Yen,'' the most ever made for a ''Kamen Rider'' season.

** Another Diend's costume is used by using both [[Series/SamuraiSentaiShinkenger Chinomanako Diend Form]] and Another Decade.

** Kamen Rider Shinobi's costume is made with parts from [[Series/KamenRiderGhost Kamen Rider Dark Necrom]] [[Series/KamenRiderExAid with the shoulder armor and retooled Ride-Player helmet.]]

*** In the ''Rider Time Shinobi'' spin-off, his own secondary rider Kamen Rider Hattari's helmet and suit is retooled from [[Series/KamenRiderDrive Kamen Rider Dark Drive.]]
*** Also Yami Shinobi, The BigBad of ''Rider Time Shinobi'' has his suit recycled from Another Shinobi an enforced version of this trope.
** Kamen Rider Quiz's costume is a retooled Ghost helmet on a similarly retooled standard Ex-Aid rider body.
** Kamen Rider Kikai's costume is a remodeled version of the [[Series/KamenRiderBuild Guardians]] helmet and armor suit. Unlike the previous two who uses parts of past riders his suit is a retooled {{Mooks}} suit. [[spoiler: Fittingly, he's actually part of the Humanoise's ground forces who had a HeelFaceTurn, meaning he's actually an EliteMook.]]
** Kamen Rider Ginga’s helmet is retooled from [[Series/KamenRiderWizard Kamen Rider Mage's]] helmet and costume is a modified version of Kamen Rider Fourze Meteor Fusion States with Meteor's regular legs and feet.

** [[BatOutOfHell Another Kiva's]] head is a redesign of the [[Series/KamenRiderW Bat Dopant's head.]]

* RecycledScript: Quite a few beats in the final arc feel like they were copied from ''Series/KamenRiderBuild'''s finale, right down to [[spoiler:the hero shouting the villain's name after he kills one of the Riders. Besides that we've got an OmnicidalManiac trying to destroy everything, the Riders dying one-by-one in the FinalBattle (with one of them getting a broken faceplate) and a ResetButtonEnding that restores everyone to life. Hilariously, Evolt was present in both final battles]].

** ''Series/KamenRiderBuild'': Sento Kiryū/Kamen Rider Build, Ryūga Banjō/Kamen Rider Cross-Z, Kazumi Sawatari/Kamen Rider Grease, Gentoku Himuro/Kamen Rider Rogue and Misora Isurugi.
** ''Series/KamenRiderExAid'': Emu Hōjō/Kamen Rider Ex-Aid, Hiiro Kagami/Kamen Rider Brave, and Kuroto Dan/Kamen Rider Genm.
** ''Series/KamenRiderFourze'': Chūta Ōsugi, [[Film/KamenRiderXKamenRiderWizardAndFourzeMovieWarUltimatum Daita "Kong" Kondō and Chikao "Nezumi" Nezu]].[[note]]Sōta Fukushi and Ryō Yoshizawa were too busy filming ''Film/{{Bleach}}'' to appear as Gentarō and Ryūsei, but Fukushi was able to record voice-overs that Toei used along with their FakeShemp[[/note]]

** ''Series/KamenRiderWizard'': Kōsuke Nitō/Kamen Rider Beast.

* CashCowFranchise: The Ridewatches have a lineup that, when including giveaways, limited items, and other obscure sources, numbers at approximately ''246'' unique watches. This includes all upgraded and final forms for every phase 2 Heisei Rider (barring [[Series/KamenRiderExAid Brave Level 50]], but including [[Theatre/KamenRiderZangetsuGaimGaiden Zangetsu Kachidoki Arms]]), every final form for every primary phase 1 Heisei Rider and some forms/watches for the other Riders, and even some hypothetical or ''SIC Hero Saga''-exclusive forms like [[Series/KamenRiderDouble CycloneAccelExtreme]] and [[Series/KamenRiderRyuki Ouja Survive]]. All without ''any'' indication that they'd ever be used in the show or related material, and even ignoring that the super form Ridewatches are [[DepartmentOfRedundancyDepartment redundant]] to the Decade Ridewatch's functions. Bandai even tried to go even further by including basic alternate forms as part of the lineup, before being rejected in polls.

** ''Series/KamenRiderDecade'': Tsukasa Kadoya/Kamen Rider Decade, Daiki Kaito/Kamen Rider Diend, Yusuke Onodera/Kamen Rider Kuuga and Narutaki.
** ''Series/KamenRiderDouble'': The Master of Fumen, Katsumi Daido/Kamen Rider Eternal and Ryu Terui/Kamen Rider Accel.

** ''Series/KamenRiderRyuki'': Shinji Kido/Kamen Rider Ryuki[[note]]Takamasa Suga voices the character via TheFaceless in ''Heisei Generations FOREVER'' before appearing in the show.[[/note]], Dark Shinji/Kamen Rider Ryuga, Daisuke Okubo, Ren Akiyama/Kamen Rider Knight, Goro Yura/Kamen Rider Zolda, Miyuki Tezuka/Kamen Rider Raia, Jun Shibaura/Kamen Rider Gai, Takeshi Asakura/Kamen Rider Ouja and Kamen Rider Odin.

** ''Series/KamenRiderDrive'': Go Shijima/Kamen Rider Mach, Krim Steinbelt/Mr. Belt, and Chase/Kamen Rider Proto-Drive/Mashin Chaser/Kamen Rider Chaser.

** ''Series/KamenRiderRyuki'': Shinji Kido/Kamen Rider Ryuki[[note]]Takamasa Suga voices the character via TheFaceless in ''Heisei Generations FOREVER'' before appearing in the show.[[/note]], Dark Shinji/Kamen Rider Ryuga, Daisuke Okubo, Ren Akiyama/Kamen Rider Knight, Goro Yura/Kamen Rider Zolda, Miyuki Tezuka/Kamen Rider Raia, Jun Shibaura/Kamen Rider Gai and Takeshi Asakura/Kamen Rider Ouja.

* {{Jossed}}: Not a theory specific to this show, but rather, one for the entire franchise, the Number theory. It's generally agreed that ''Decade'', ''Double'', ''OOO'', and ''Fourze'' had a theme revolving around 1, 2, 3, and 4 respectively[[note]]all 4 transform using their corresponding number of TransformationTrinkets, all had their corresponding number in their title in some form, and there's a few unique to each show[[/note]], but the theory also believed that it continued onwards[[note]]5 for ''Wizard'', 6 for ''Gaim'', 7 for ''Drive'' and so on[[/note]]. Although the producer of ''Ex-Aid'' explicitly said that said series was based around the number 10, there was still a tiny bit of discussion during ''Build'', but this series put the final nail in the coffin for the theory, since not only was this series (which, if the theory was true, would've been themed around 11) themed around the number 20 if it ''is'' supposed to be themed after a number[[note]]20th anniversary, 20th Heisei-era rider, 20 Ridewatches, and Sougo gaining his Zi-O II form 20 episodes after becoming a rider[[/note]], but Shirakura [[https://twitter.com/cron204/status/1095471070776221697 explicitly stated]] it was a coincidence during the run of this series.

* ActorAllusion:
** Or rather, Suit-Actor Allusion, for Geiz's suit actor Yuya Nawata. In the ''OOO Arc'', Geiz gets the Genm Armor, which is based off [[Series/KamenRiderExAid Kamen Rider Genm]], Nawata's first in-suit role as a Kamen Rider.
** Creator/RikiyaKoyama as the EvilCounterpart of TheHero from another timeline? [[Film/KamenRiderXKamenRiderGaimAndWizardTheFatefulSengokuMovieBattle Sounds familiar.]]

* CastingGag:
** While Creator/RikiyaKoyama has voiced BigBad-types before, his first scene in this show involves curbstomping waves of freedom fighters very similar to [[Series/KamenRiderBlackRX Joe the Haze.]]
*** He has also played a character whose main method of fighting involves [[LightNovel/FateZero manipulating time]].
** This is not first time that Hideya Tawada played a [[StealthPun shinobi]] [[Series/ShurikenSentaiNinninger in another series written by Kento Shimoyama]].
** Jingi Irie previously starred as the titular human-robot {{Series/Kikaider}} from the recent Kikaider Reboot movie. The episode he premeres in is even called "It's Kikai! 2121", or in Japanese: "[[ShoutOut Kikaidā]]! 2121".
** This is not the first time Amane Kurihara's actress, Hikari Kajiwara, guest starred as a MonsterOfTheWeek character. She was also previously [[Series/KamenRiderFourze Ritsuko Usaka/Altar Zodiarts]].
** Creator/TomokazuSugita has two cases: He's the voice actor of the Kivat family in ''Series/KamenRiderKiva'', as the ''Kiva'' arc is Ginga's debut episode. Additionally, his voice actor is also the titular hero of ''Series/UltramanGinga'', as well as the fact that both characters are from the future.
** Katsuhisa Namase (Junichiro Tokiwa) previously starred in ''Keibuho Yabe Kenzo'', a TV series that had featured several ''Kamen Rider'' alumni as guest stars and lampshaded the everloving '''hell''' out of it by having every single aspect of their characters be a reference to their ''Rider'' role. Even better, several of those guest stars went on to appear in ''Zi-O'' itself alongside Namase.

* DoItYourselfThemeTune:
** "Zi-O! King of time!" is sung by So Okuno.
** "Future Guardian" Geiz' {{Leitmotif}} is sung by Gaku Oshida.
** "Black&White" is sung by Keisuke Watanabe.
** "Tsuki no Michiru Toki" is sung by Shieri Ohata.
** "Revolutionize" is sung by Rihito Itagaki, Ayaka Konno, and Kentaro Kanesaki.
** The theme for Rider Time: Shinobi "IZANAGI" is sung by Hideya Tawada.

* RealLifeWritesThePlot:
** In general, this happens whenever one of the actors can't reprise their role due to scheduling conflicts. Usually, this happens because many of them has reached stardom, which ironically, is often due to their breakthrough role in Kamen Rider.
** Episode 6.5 openly admits that the Fourze arc was hamstrung because both Souta Fukushi and Ryo Yoshizawa (Gentaro/Fourze and Ryusei/Meteor) couldn't reprise their roles because they were busy filming the live-action ''Film/{{Bleach}}'' movie[[note]]Though Fukushi was able to record voice-overs that were dubbed onto the FakeShemp Gentaro who appears during the arc[[/note]]. In order to patch the holes left by their absence, the arc was tied in with ''Faiz'', aided by the fact that it's ''Faiz''[='s=] 15th anniversary and both Kento Handa and Kohei Murakami (Takumi/Faiz and Kusaka/Kaixa) were available to return. There are still a few hints of the arc's [[WhatCouldHaveBeen original intentions]], primarily that Another Fourze/Faiz is a ShadowArchetype for Ryusei. The writing staff was able to spin this to tie the plot in with Faiz by revealing that both Another Fourze/Faiz and the girl he's trying to save were members of the Ryusei School, turning the hints towards Meteor into a RedHerring.
*** This ended up wedging Fourze’s heavy theme of friendship into 555's tribute plot, resulting in rather [[NotHimself significant]] [[{{Retcon}} changes]] to 555's characters from the events of 555 being erased from history. The biggest offender of this being Kusaka, originally a [[ManipulativeBastard manipulative]] [[ItsAllAboutMe self-centered]] HateSink [[JerkWithAHeartOfJerk jerkass with no redeeming qualities]], he is now a rather selfless WellIntentionedExtremist who [[ThisIsSomethingHesGotToDoHimself takes it upon himself]] to save his friends even if it means risking his own life. Keep in mind this isn't [[Film/HeiseiRiderVsShowaRiderKamenRiderWarsFeaturingSuperSentai the first time]] things from 555's was retconned with Shinichiro Shirakura as producer to give Kusaka more sympathy. Of course, [[InSpiteOfANail it apparently doesn't really try to change how much of an arrogant jerk he is anyway]], with Takumi considering him [[TheFriendNobodyLikes someone he doesn't even like that much, but still happens to be his friend]].
** Episode 9.5 lampshades that Kuroto Dan's appearance in the OOO tribute arc was due to Tetsuya Iwanaga's busy schedule only allowing him to return during the time they were filming the OOO arc, with the story written around this to involve him in the plot as Another OOO, as well as having the release of a Genm Ridewatch product campaign scheduled together with the release of ''OOO''-related ''Zi-O'' products in November 2018 to accommodate this.
** Episode 13.5 reveals the Ghost tribute arc was delayed due to Shun Nishime being busy with filming and stage play commitments, hence Zi-O's use of the Ghost Armor being rather late despite Geiz having the Ridewatch to begin with. When asked about the possibility of Ryoma Takeuchi returning for Drive however, Nishime/Takeru advised everyone not to talk about it.
** Miho Kirishima/Kamen Rider Femme’s absence in ''Rider Time: Ryuki'' owes to her actress, Natsuki Katou, giving birth to her second child at the time it was being filmed. This is the reason Abyss (originally from ''Decade'') is one of the 13 Riders in the new Rider War instead of Femme.
** The ''Hibiki'' arc using Kyosuke instead of Hibiki or Asumu is likely due to this, with Hibiki's actor having been fired and blacklisted due to power-harassment allegations[[note]]although reportedly, he swore he'd never return, so even if he wasn’t blacklisted, he likely wouldn't have reprised his role anyways[[/note]], and the latter due to his actor retiring in 2018. Jouji Shibue wasn't able to reprise his role as Iori Izumi/Kamen Rider Ibuki either due to being busy filming on ''Series/KishiryuSentaiRyusoulger''. Kenji Matsuda didn't reprise his role as Kamen Rider Zanki, likely because Hibiki's history was not erased since Another Hibiki was created in 2019. As a result, Zanki [[spoiler: remains dead]].
** Decade’s increased appearances from the ''Kabuto'' arc onwards were due to Masahhiro Inoue’s schedule being busy prior to this.
** Most ironically, however, is that ''Zi-O'' did not have the major RealLifeWritesThePlot event that allowed ''Series/KaizokuSentaiGokaiger'' to enjoy a massive boom of eager returning veteran actors, namely the 2011 Tohoku earthquake and tsunami[[labelnote:Explanation]]Originally, ''Gokaiger'' was just going to have tribute episodes related to its MechaExpansionPack, meaning only less than a third of all then-34 previous teams would have been given proper attention. However, days after the quake and tsunami hit on March 11, a Twitter feed was setup by Teruaki Ogawa ([[Series/NinjaSentaiKakuranger [=NinjaRed=]]] and [[Series/SeijuuSentaiGingaman BlackKnight Hyuuga]]) to allow other veteran actors not just from ''Super Sentai'' but from across all tokusatsu to spread encouraging messages to the people. Through this, many Sentai veterans discovered about Gokaiger and wanted in, even those who had retired like Ogawa's co-star, Kazuki Maehara ([=GingaRed=]). This explains the clearly-shoehorned-in cameos in the ''Gokaiger Goseiger 199'' crossover movie that would be released soon after. That Naruhisa Arawaka was able to seamlessly integrate new tribute episodes is likewise a testament to his skill as a writer[[/labelnote]].

* FlipFlopOfGod: Masahiro Inoue said that the series finale would be the final time he played Decade, but then he proceeded to star in the Decade vs Zi-O/Zi-O vs Decade two part special, which he claims will be the last time. Though he mentioned on a live stream with Kimito Totani that the reprisals would never end. It implies that while Masahiro is okay with reprising his role as Decade, but wants a fairly long break before his next appearance.

* RecycledScript: Quite a few beats in the final arc feel like they were copied from ''Series/KamenRiderBuild'''s finale, right down to [[spoiler:the hero shouting the villain's name after he kills one of the Riders. Besides that we've got an OmnicidalManiac trying to destroy everything, the Riders dying one-by-one in the FinalBattle and a ResetButtonEnding that restores everyone to life. Hilariously, Evolt was present in both final battles]].

** The then 21 years old Gaku Oshida and 20 years old Sheiri Ohata portrays 18-years-old Geiz and Tsukiyomi respectively.

** Jingi Irie previously starre d as the titular human-robot {{Series/Kikaider}} from the recent Kikaider Reboot movie. The episode he premeres in is even called "It's Kikai! 2121", or in Japanese: "[[ShoutOut Kikaidā]]! 2121".

** So Okuno pulls triple duty as Prime Sougo, Sougo from 3 days in the Future ("Gaim Arc"), and Dark Sougo ("Ryuki Arc"). ''Zi-O vs. Decade'' takes it UpToEleven by having him portray the prime Sougo and ''six'' alternate versions of him, all with separate personalities.

* TheWikiRule: Covered as part of [[http://kamenrider.wikia.com/wiki/ Kamen Rider Wiki]], and as an individual series on the [[http://kamenriderzio.wikia.com/wiki/ Kamen Rider Zi-O Wiki]].

** ''Series/KamenRiderDecade'': Tsukasa Kadoya/Kamen Rider Decade, Daiki Kaito/Kamen Rider Diend, Yusuke Onodera/Kamen Rider Kuuga and Tatsuhito Okuda/Narutaki.

* FlipFlopOfGod: Masahiro Inoue said that the series finale would be the final time he played Decade, but then he proceeded to star in the Decade vs Zi-O/Zi-O vs Decade two part special, which he claims will be the last time.

** Totani Kimito reprised his role as Daiki Kaito in the series, and was also planning to return for ''Decade vs Zi-O'', but had to turn it down to take care of one of his sick parents.

** Totani Kimito reprised his role as Daiki Kaito in the series, and was also planning to return, but had to turn it down to take care of one of his sick parents.