History Series / ToeiUniverse

* ''Series/KamenRiderOOO'' (2010-11): Episodes 27 & 28 celebrate the 999th and 1000th episodes of the whole franchise by BreakingTheFourthWall to have the cast film their own movie adaptation of the original series, with Kougami watching all the previous shows (including the nonexistent ''Riderman'' and ''ZX'' seasons) and a [[{{Mook}} Shocker Combatman]] as the VictimOfTheWeek hosting the episodes' Yummy to recreate footsoldiers from prior seasons. Provides a SequelHook to ''Fourze'' by having two supporting characters make TheCameo in the final episode.

** ''[[Recap/KamenRiderDriveSecretMissionTypeLUPIN Secret Mission Type LUPIN: ~Lupin, The Last Challenge~]]'' (2015): Bonus special included in the ''Magazine/TeleviKun'' magazine. AllThereInTheManual sets it between ''Drive Saga: Chaser'' & episode 41, but the Roidmude count sets it between 42 & 43.

** '' Kamen Rider Drive: ~Mach Saga~'' (2016): TieInNovel focusing on Gō Shijima/Kamen Rider Mach, acting as a prologue to the second set of ''Drive Saga'' movies and reintroducing Roidmude 005 from the ''Type TV-KUN'' special as the BigBad. Set after Shinnosuke & Kiriko's wedding in ''Super Movie War Genesis'' and before the ''Kamen Rider Mach Dream Story'' drama CD.

* ''Series/KamenRiderGhost'' (2015-16): [=ZyuohEagle=] from ''Doubutsu Sentai Zyuohger'' appears in an episode to promote the ''Kamen Rider 1'' movie. Features an EarlyBirdCameo by Ex-Aid in TheMovie, his dark counterpart Genm in the penultimate episode, and both Ex-Aid & Genm in the finale.
** Crossed over with ''Drive'' in ''Super Movie War Genesis''. Notably, the TieInNovel sequel to the ''Kamen Rider Specter'' V-Cinema handwaves the continuity errors in ''Super Movie War Genesis'' as the events of that movie taking place in an AlternateTimeline.
** Crossed over with the original ''Kamen Rider'' in ''Kamen Rider 1'', which was promoted by the crossovers with ''Zyuohger'' and a miniseries featuring villains from the previous Heisei Phase 2 seasons.

** ''[[Theatre/KamenRiderZangetsuGaimGaiden Kamen Rider Zangetsu -Gaim Gaiden-]]'' (2019): A stageplay set years after the series, focusing on Takatora Kureshima. His Shin Kachidoki Arms form introduced here will later appear in the ''Zi-O'' summer movie and the ''Gaim Gaiden: Gridon VS Bravo'' set.

** ''Film/KamenRiderDriveSurpriseFuture'' (2015): TheMovie for ''Drive'', set between episodes 40 & 41, with the ''Drive Saga: Chaser'' V-Cinema taking place immediately after.

* ''Series/KamenRiderWizard'' (2012-13): Closes with a TwoPartEpisode in which Wizard ([[TheSixthRanger and Beast]]) are transported to an AlternateUniverse along with the first thirteen Heisei Rider protagonists and the new guy, Gaim.
** Crossed over with ''Fourze'', ''OOO'', and ''Double'' in ''Film/KamenRiderXKamenRiderWizardAndFourzeMovieWarUltimatum'' (2012). AlternateContinuity versions of the protagonists from ''Series/Akumaizer3'' and ''Series/BishoujoKamenPoitrine'' feature as well. Set before episode 14.

** ''Film/KamenRiderGaimGreatSoccerBattleGoldenFruitsCup'' (2014): TheMovie for ''Gaim, taking place after its tie-in episode, #37. The BigBad of the movie returns in the post-TimeSkip epilogue episode #47.

** This changes with the SequelSeries, ''Series/KamenRiderBlackRX'' (1988-89), essentially the second season of ''Black'' with Kotaro Minami continuing on as protagonist, which reintroduces the first ten Kamen Riders in its final episodes. The BigBad, Emperor Crisis, is also heavily implied to be the original Great Leader, sharing the same voice actor, presenting himself as the embodiment of evil and treating the assembled Riders as old enemies.

* Then there's ''Film/KamenRiderWorld'' (1994); a short film which united ZO and J against a VillainTeamUp consisting of, as well as a monster from ''Shin'' and the baddies from ''J'', two bad guys from ''Black'' (that is, Black's nemesis Shadow Moon and a MonsterOfTheWeek). Thus, this film connects all three 90s movies back to the original.

** ''[[VideoGame/KamenRiderSeigiNoKeifu Kamen Rider: Genealogy of Justice]]'': A video game that acts as a story set three months after ''Agito'' crossing over the original ''Kamen Rider'' series, ''[=V3=]'', and ''Black'' via time travel, and notably treats ''Agito'' as taking place in 2003-2004, two years after the 2000-2001 date established as ''Kuuga'''s setting.

** ''Cho Kamen Rider Den-O & Decade Neo Generations: The Onigashima Warship'' (2009): The first installment in the ''Cho Den-O'' sub-franchise, taking place directly after episode 15 of ''Decade''.
** ''Kamen Rider × Kamen Rider × Kamen Rider The Movie: Cho Den-O Trilogy'' (2010): A trilogy of DayInTheLimelight movies in the ''Cho Den-O'' sub-franchise, the first two of which focus on ''Den-O'' characters. The only actual narrative throughline connecting them is the first two films setting up a gag that pays off at the end of the third one.

** Episodes 26 & 27 are tributes to ''Black'' and ''Black RX'', featuring the two versions of Kotaro Minami teaming up. Later crossovers will continue to depict the two as separate Riders despite both being Kotaro, implicitly treating one or both of them as hailing from one of the worlds in these episodes but generally not bothering to explain it. The episodes also introduce Dai-Shocker as the main antagonists, a new iteration of Shocker from the original series and expanding the anniversary celebration beyond the Heisei era.

** TheMovie was a tribute episode for ''Drive'', as well as "Lost Heisei Riders" i.e. ''Black RX'' which began in the Shōwa era but finished in the Heisei era, the three films from the 90's, and ''Amazons'', and had a cameo from the protagonists of ''Kamen Norider'', ''G'', and the ''Kuuga'' manga. Also has an EarlyBirdCameo by Zero-One in TheStinger[[note]]WordOfGod claims this movie split into an AlternateTimeline's ending that leads into the ''Final Stage'' show, but its effect on the status quo and narrative is referenced just enough that BroadStrokes versions of its events must have occurred in the series[[/note]].

** ''Recap/KamenRiderDriveSagaKamenRiderBrain'' (2019): Originally an AprilFoolsJoke based on an offhand line from Brain at the end of ''Drive Saga: Heart'', only to later be made an actual miniseries focused on the Brain Roidmude becoming Kamen Rider Brain. Most of it turned out to be AllJustADream, but Kamen Rider Brain later cameos in TheMovie for ''Zi-O'' and makes a proper appearance in ''Kamen Rider Outsiders''.

** The ''Deneb Kanjinchou'' (2020) novel focusing on Deneb and Zeronos features elements of ''Zi-O'' and takes place after its tribute episodes.

** The ''Den-O'' tribute episodes serve as the basis for the ''Cho Den-O'' sub-franchise, and notably take steps to imply that the World of Den-O visited by Decade is the original setting of the ''Den-O'' TV series, handwaving the differences with a TimeyWimeyBall instead of chalking it up to an alternate universe like the other A.R. Worlds visited.

** ''Episode Yellow: Treasure '''DE End''' Pirates'' (2010): The finale to the ''Cho Den-O Trilogy'', focusing on Daiki Kaito/Kamen Rider Diend and delivering the punchline to the gag that was set up in the previous two ''Cho Den-O'' movies.

** Crossed over with ''Decade'' in ''Film/KamenRiderxKamenRiderWDecadeMovieWar2010'' ([[NonIndicativeTitle released in 2009]]), which was the FullyAbsorbedFinale to ''Decade'''s story and is set between episodes 12 & 13 of ''Double''.

** Crossed over with ''Gaim'' in ''Movie War Full Throttle'', which also had a FreezeFrameBonus in the background depicting a landmark from ''Double''. Also crossed over with Accel from ''Double'' in the ''Drive Saga: Chaser'' V-Cinema.
** Crossed over with ''Shuriken Sentai Ninninger'' to promote ''Super Hero Taisen GP'' (though the special notably treats ''Drive'' and ''Ninninger'' as being in separate universes). The movie itself primarily takes place in an altered timeline, but depicts exactly one Roidmude elimination in the count just prior to the timeline being changed. Said movie's sequel miniseries ''Kamen Rider 4'' crosses over with ''Den-O'' and acts as a FullyAbsorbedFinale to ''555''.

* ''Series/KamenRiderGaim'' (2013-14)
Began the tradition of ''Rider'' and ''Sentai'' having crossovers to promote the new spring movie, by having a crossover with ''Ressha Sentai [=ToQger=]'' in ''[[Recap/ResshaSentaiTokkyugerVsKamenRiderGaim Ressha Sentai [=ToQger=] vs. Kamen Rider Gaim Spring Vacation Combining Special]]'', which features a surprise cameo by Narutaki from ''Decade'' to promote ''Kamen Rider Taisen''.
** Crossed over with ''Wizard'' in ''Film/KamenRiderXKamenRiderGaimAndWizardTheFatefulSengokuMovieBattle'', which was a FullyAbsorbedFinale to ''Wizard'' and featured an alternate universe of Bujin Rider counterparts to the first fifteen leading Heisei Riders, and which introduces the Legend Rider Lockseeds and Rider Arms forms that appear in later crossovers. Set between episodes 9 & 10, with ''Gaim Gaiden: Duke'' taking place before it.
** ''Film/HeiseiRiderVsShowaRiderKamenRiderWarsFeaturingSuperSentai'' and its prequel reintroduce the Badan Empire from ''ZX'' as its main antagonists, as well as the OriginalGeneration Kamen Rider Fifteen among their ranks using the Legend Rider Arms. The movie also gives particular narrative focus to returning Riders from both the Heisei and Shōwa eras; Decade, Faiz, ZX, X-Rider, and the original Kamen Rider 1.

* ''Series/KamenRiderGaim'' (2013-14): Began the tradition of ''Rider'' and ''Sentai'' having crossovers to promote the new spring movie, by having a crossover with ''Ressha Sentai [=ToQger=]'' which features a surprise cameo by Narutaki from ''Decade'' to promote ''Kamen Rider Taisen''.
** Crossed over with ''Wizard'' in the ''Sengoku Movie Battle'', which was a FullyAbsorbedFinale to ''Wizard'' and featured an alternate universe of Bujin Rider counterparts to the first fifteen leading Heisei Riders, and which introduces the Legend Rider Lockseeds and Rider Arms forms that appear in later crossovers.
** ''Kamen Rider Taisen'' and its prequel reintroduce the Badan Empire from ''ZX'' as its main antagonists, as well as the OriginalGeneration Kamen Rider Fifteen among their ranks using the Legend Rider Arms. The movie also gives particular narrative focus to returning Riders from both the Heisei and Shōwa eras; Decade, Faiz, ZX, X-Rider, and the original Kamen Rider 1.

** Crossed over with ''Double'' in 'Kamen Rider × Kamen Rider OOO & W Featuring Skull: Movie War Core'' (2010). While there are numerous continuity problems that prevent it from fitting neatly with ''OOO'' (though it is definitely canon to ''Double''), the ''OOO'' TieInNovel does attempt to explain at least one of those contradictions.

* ''Film/KamenRiderG'' (2009) is an AffectionateParody short which features Decade (and the first nine Heisei Riders) dropping in on the eponymous hero via a dimensional wall. The eponymous Rider fights against the organization Shade which, due to a reuse of costumes, has its ranks made up of modified humans who assume the form of Worms from ''Kabuto'', whilst G rides V3's Hurricane bike from ''Kamen Rider The Next''. A Neo-Shade appears in ''Series/KamenRiderDrive''. G later cameos in TheMovie for ''Kamen Rider Zi-O'' alongside other "Lost Heisei Riders". As in the real world, ''Super Sentai'' exists as a TV Asahi production in this reality as evidenced by the appearance of a poster for ''Gekiranger vs. Go-Onger''.

** ''Saraba Kamen Rider Den-O: Final Countdown'' (2008): The third ''Den-O'' movie after ''Climax Deka'' (see below), introducing Den-O's Grand{{kid from the Future}} New Den-O, who will serve as the representative for this series in later crossovers in place of Ryotaro Nogami due to the actor's StarMakingRole catapulting him far beyond Toei's paygrade.

*** ''Episode Red: Zero No Star Twinkle'' focuses on Yuto Sakurai aka Kamen Rider Zeronos, the Secondary Rider of ''Den-O''.
*** ''Episode Blue: The Dispatched Imagin is [=NEWtral=]'' centers on Kōtarō Nogami aka Kamen Rider New Den-O and Teddy from the ''Final Countdown'' movie.

** ''Episode Yellow: Treasure DE End Pirates'' (2010): The finale to the ''Cho Den-O Trilogy'', focusing on Daiki Kaito/Kamen Rider Diend and delivering the punchline to the gag that was set up in the previous two ''Cho Den-O'' movies.

** The film ''Film/KamenRiderKabutoGodSpeedLove'' (2006) is set in an alternate timeline but, unlike other such films, ties back to continuity as a change in the past creates the TV series timeline.

** ''Film/KamenRiderBladeMissingAce'' (2004): TheMovie for ''Blade'', set in an AlternateContinuity where the finale ended with [[spoiler:Kazuma sealing away Hajime instead of turning himself into an Undead]].

** ''Film/KamenRiderTheNext'': A sequel to ''The First'' set in its continuity, adapting ''[=V3=]''. The remake version of [=V3=] appears with his predecessors in the ''Zi-O'' stage show.

** More directly, the ''ZO VS J'' (2005) edition of ''Literature/Literature/SICHeroSaga'' crosses over its title characters.

** The Hyper Battle DVD special has Ryuki meeting the unfamiliar Agito, but it was AllJustADream.

* ''Series/KamenRiderBlade'' (2004-05): The [[MilestoneCelebration 20th anniversary]] stage show acts as a bridge to smooth over any {{Series Continuity Error}}s between the ''Blade'' cast's EarnYourHappyEnding in ''Zi-O'''s tribute episodes to it and the DistantFinale events depicted in the two ''Blade'' novels.
* ''Series/KamenRiderHibiki'' (2005-06): The ''Hibiki'' novel set in the Edo era is a crossover with ''Henshin Ninja Arashi''.

** One of the ''Den-O'' novels focusing on Deneb and Zeronos features elements of ''Zi-O'' and takes place after its tribute episodes.
* ''Series/KamenRiderKiva'' (2008-09): ''Kiva'' and ''Den-O'' crossover in ''Climax Deka''.

** Starts the tradition of the new Rider making an EarlyBirdCameo in TheMovie, first with Double himself debuting in Decade's movie, then with the appearance of OOO in Double's movie (which fits into ''Double'''s continuity).
** Crossed over with ''Decade'' in ''Movie War 2010'', which was the FullyAbsorbedFinale to ''Decade'''s story.

* ''Series/KamenRiderOOO'' (2010-11): Provides a SequelHook to ''Fourze'' by having two supporting characters make TheCameo in the final episode.
** Crossed over with ''Double'' in ''Movie War Core''. While there are numerous continuity problems that prevent it from fitting neatly with ''OOO'' (though it is definitely canon to ''Double''), the ''OOO'' TieInNovel does attempt to explain at least one of those contradictions.
** TheMovie hosts the debut of Fourze himself. It also acts as a crossover with ''Series/AbarenboShogun'', using a CelebrityParadox and time travel to imply it is simultaneously a ShowWithinAShow to ''OOO'' and set in the same universe.

** Crossed over with ''OOO'', ''Double'', and the original Seven Legendary Riders in ''Movie War Mega Max'' to fight against Foundation X.
** TheMovie hosts the debut of Wizard as a Rider. AlternateContinuity versions of the heroes from ''Series/SpaceIronmenKyodain'' serve as the main antagonists.

** Crossed over with ''Fourze'', ''OOO'', and ''Double'' in ''Movie War Ultimatum''. AlternateContinuity versions of the protagonists from ''Series/Akumaizer3'' and ''Series/BishoujoKamenPoitrine'' feature as well.

* ''Film/KamenRiderVsShocker'' (1972): The first movie in the series to tell an original story (the previous movie ''Go Go Kamen Rider'' having been a theatrical release of episode 13), released on the same day as episode 51 and set between it and 52.

* ''Series/KamenRider'' is the first series of the ''Franchise/KamenRider'' franchise, introducing heroes Takeshi Hongo and Hayato Ichimonji, [[Main/TheMentor Tobei Tachibana]] and the evil organization Shocker led by the mysterious [[Main/BigBad Great Leader]].
** ''Film/KamenRiderTheFirst'': A ContinuityReboot movie of the original series, helmed by Creator/ToshikiInoue, son of the original show's head writer Masaru Igami. The remake version of Takeshi Hongo cameos in episode 14 of ''Kamen Rider Kabuto'', and returns in ''Kamen Rider Zi-O: Final Stage'', linking the film to the main continuity and its multiverse much like ''Kikaider'' and its own reboot are as described below.

* ''Series/KamenRiderV3'' directly follows the original and reprises the aforementioned characters as the new hero fights the Great Leader's Destron organization.

* Beyond the name "Kamen Rider", ''Series/KamenRiderX'' initially starts independent of its predecessors, with new villains. This soon changes when Tobei Tachibana, bringing with him his knowledge of the previous Riders, takes the eponymous X-Rider under his wing. A RecapEpisode of the first two shows cements the connection, reintroducing V3 then his predecessor Rider 2 as recurring characters, with the first five Kamen Riders united in TheMovie, ''Film/FiveRidersVsKingDark''.

* ''Series/KamenRiderAmazon'' has no appearance from previous Riders, but does reintroduce Tobei Tachibana as ''X'' did, and a child recognises Amazon as "Kamen Rider".
* ''Series/KamenRiderStronger'', the last series of ''Kamen Rider'''s first televised run, also includes Tobei Tachibana as well as a new band of villains led by the same Great Leader last seen in ''V3''. The first six Kamen Riders come BackForTheFinale, where the Great Leader also takes credit as TheManBehindTheMan for the bad guys in both ''X'' and ''Amazon''. The finale is followed by a RecapEpisode of the entire franchise up to that point.
* ''Series/KamenRiderSkyrider'', officially known as simply ''Kamen Rider'', was originally conceived as a ContinuityReboot with a new Rider facing the Great Leader's Neo-Shocker. Instead of Tobei Tachibana, this Rider was assisted by a SuspiciouslySimilarSubstitute named Genjiro Tani. The series eventually reintroduces the first Seven Legendary Riders as recurring characters.
* Following Skyrider was ''Series/KamenRiderSuper1'', featuring an independent Kamen Rider and RoguesGallery with no appearance from previous Riders (on TV that is). That said, Genjiro Tani returns as the mentor, and the first eight Riders return to help Super-1 in [[Film/KamenRiderSuper1 his movie]].
* ''Film/BirthOfTheTenthGatherAllKamenRiders'' was a TV special which doubled as a RecapEpisode of the whole franchise and introduced the tenth Rider, ZX, who fought with his nine predecessors against the Badan Empire, led by the same Great Leader. Officially, Toei considers the special to be the first, last, and only episode of its own ''Kamen Rider ZX'' TV series, and it is included in the count leading up to ''Kamen Rider OOO'''s celebration of the 999th and 1000th episodes of the franchise.
** ''Manga/KamenRiderSpirits'': An AdaptationExpansion of the ZX story, including details and answers about other Riders like explaining Riderman's UnexplainedRecovery. One of the powers ZX demonstrates in this manga became a CanonImmigrant in ''Kamen Rider Taisen'', which partially functions as a 30th anniversary celebration of the ''ZX'' special.
* ''Series/KamenRiderBlack'' is, continuity-wise, totally independent of the previous Kamen Rider series. In fact, the protagonist, Kotaro Minami, coins the name himself.
** This changes with the SequelSeries, ''Series/KamenRiderBlackRX'', essentially the second season of ''Black'' with Kotaro Minami continuing on as protagonist, which reintroduces the first ten Kamen Riders in its final episodes. The BigBad, Emperor Crisis, is also heavily implied to be the original Great Leader, sharing the same voice actor, presenting himself as the embodiment of evil and treating the assembled Riders as old enemies.

** ''Film/ShinKamenRiderPrologue'': AllThereInTheManual materials retroactively declare that the Foundation that serves as the GreaterScopeVillain of this movie is connected to Foundation X, which is formally introduced in ''Kamen Rider Double'' as mentioned below.
** ''Film/KamenRiderZO''
** ''Film/KamenRiderJ''
* Then there's ''Film/KamenRiderWorld''; a short film which united ZO and J against a VillainTeamUp consisting of, as well as a monster from ''Shin'' and the baddies from ''J'', two bad guys from ''Black'' (that is, Black's nemesis Shadow Moon and a MonsterOfTheWeek). Thus, this film connects all three 90s movies back to the original.

** The ''Geiz, Majesty'' V-Cinema features returning appearances from the secondary Riders of ''555'', '''Double'', ''OOO'', and of course, ''Decade''.

* ''Series/KamenRiderGotchard'' (2023-24)

* ''Series/TokumeiSentaiGobusters'' (2012-2013): Guest stars the hero from ''Film/SpaceSheriffGavanTheMovie'' in a TwoPartEpisode.

** Crossed over with ''Gokaiger'' in ''Go-Busters vs. Gokaiger'', which also introduces the team from ''Kyoryuger'' and a returning appearance from Kaoru Shiba of ''Shinkenger''.

* ''Series/MashinSentaiKiramager'' (2020-2021): Had a one-episode crossover with supporting characters from ''Gekiranger''.

** The ''Super Animal War'' miniseries features [=AkaRed=] returning with another dream team of veteran Sentai Rangers, this time from ''Ninninger'', ''[=ToQger=]'', ''Kyoryuger'', and ''Go-Busters'', plus a reformed MonsterOfTheWeek from ''Gokaiger''. However, the entire miniseries takes place out of continuity with ''Zyuohger'' and has NoFourthWall, culminating in

* ''Series/KamenRiderGhost'' (2015-16): [=ZyuohEagle=] from '''Doubutsu Sentai Zyuohger'' appears in an episode to promote the ''Kamen Rider 1'' movie. Features an EarlyBirdCameo by Ex-Aid in TheMovie, his dark counterpart Genm in the penultimate episode, and both Ex-Aid & Genm in the finale.

* ''Series/KamenRiderHibiki'' (2005-06)

** Crossed over with ''Wizard'' in the ''Sengoku Movie Battle''.

* ''Series/KamenRiderGhost'' (2015-16): Features an EarlyBirdCameo by Ex-Aid in TheMovie, his dark counterpart Genm in the penultimate episode, and both Ex-Aid & Genm in the finale.

** Crossed over with the original ''Kamen Rider'' in ''Kamen Rider 1'', which was promoted by a crossover with ''Doubutsu Sentai Zyuohger'' and a miniseries featuring villains from the previous Heisei Phase 2 seasons.

** The ''Ryuki'' tribute episodes spin off into the ''RIDER TIME: Kamen Rider Ryuki'' miniseries, a sequel to the original season.
** TheMovie was a tribute episode for ''Drive'', as well as "Lost Heisei Riders" i.e. ''Black RX'' which began in the Showa era but finished in the Heisei era, the three films from the 90's, and ''Amazons'', and had a cameo from the protagonists of ''Kamen Norider'', ''G'', and the ''Kuuga'' manga. Also has an EarlyBirdCameo by Zero-One in TheStinger[[note]]WordOfGod claims this movie split into an AlternateTimeline's ending that leads into the ''Final Stage'' show, but its effect on the status quo and narrative is referenced just enough that BroadStrokes versions of its events must have occurred in the series[[/note]].

** Crossed over with ''Go-Onger'' in ''Shinkenger vs. Go-Onger'', which also starts a new tradition of EarlyBirdCameo by introducing the team from ''Goseiger''. The [[QuirkyGoldfishPoopGang Gaiark trio]] stealing [[SixthRanger Genta]]'s sushi cart and a bottle of booze from it in this movie will be a BrickJoke during their appearances in future movies.

* ''Series/KaizokuSentaiGokaiger'' (2011-2012): The 35th anniversary series, ''Gokaiger'''s setting is a world where the first 34 Super Sentai all exist, with the Gokaigers inheriting their powers and {{Continuity Cameo}}s galore.

** The crossover with ''Kamen Rider Drive'' to promote ''Super Hero Taisen GP'' notably treats ''Ninninger'' as taking place in a separate universe from ''Drive''.

* ''Series/DoubutsuSentaiZyuohger'' (2016-2017): Crossed over with ''Kamen Rider Ghost'' to promote the ''Kamen Rider 1'' movie. Guest stars the team from ''Gokaiger'' in a TwoPartEpisode to celebrate the 1999th and 2000th episodes of the franchise.

* ''Series/HyakujuuSentaiGaoranger'' (2001-2002): Crossed over with the first 24 Super Sentai in ''Gaoranger vs. Super Sentai'', which features a dream team of Sentai veterans from ''JAKQ'', ''Liveman'', ''Megaranger'', ''Gingaman'', and ''[=GoGoV=]''.

** Crossed over with ''Goseiger'' directly in ''199 Heroes'', which was a tribute episode to ''Goranger'' and featured additional returning legends and villains from ''JAKQ'', ''Denziman'', ''Goggle-V'', ''Dynaman'', ''Bioman'', ''Turboranger'', ''Dairanger'', ''Carranger'', ''Gingaman'', ''Dekaranger'', ''Magiranger'', ''Boukenger'', ''Go-Onger'', and ''Shinkenger''.

* ''Series/HyakujuuSentaiGaoranger'' (2001-2002): Crossed over with the first 24 Super Sentai in ''Gaoranger vs. Super Sentai''.

* The ''Den-O'' tribute episodes serve as the basis for the ''Cho Den-O'' sub-franchise, and notably take steps to imply that the World of Den-O visited by Decade is the original setting of the ''Den-O'' TV series, handwaving the differences with a TimeyWimeyBall instead of chalking it up to an alternate universe like the other A.R. Worlds visited.
* Episodes 24 & 25 cross over with ''Samurai Sentai Shinkenger'', tying into Acts 20-22 of the latter and treating the World of Shinkenger as a universe without Kamen Riders where the presence of a ''Shinkenger'' MonsterOfTheWeek turning into a Rider is an anomaly.
* Episodes 26 & 27 are tributes to ''Black'' and ''Black RX'', featuring the two versions of Kotaro Minami teaming up. Later crossovers will continue to depict the two as separate Riders despite both being Kotaro, implicitly treating one or both of them as hailing from one of the worlds in these episodes but generally not bothering to explain it. The episodes also introduce Dai-Shocker as the main antagonists, a new iteration of Shocker from the original series and expanding the anniversary celebration beyond the Heisei era.

** Crossed over with ''Build'' in ''Heisei Generations FOREVER'', which also functions as a tribute episode dedicated to ''Double'', ''Den-O'', and particularly ''Kuuga'', and is a RealWorldEpisode[[note]]WordOfGod claims this movie is CanonDiscontinuity, but a BroadStrokes versions of its events must have occurred in the series to explain the acquisition of the Double and Kuuga Ridewatches[[/note]].

* ''Series/GoGoSentaiBoukenger'' (2006-2007): Crossed over with the first 29 Super Sentai in ''Boukenger vs. Super Sentai'', which introduces [=AkaRed=], a character that appears in subsequent anniversaries.

** Crossed over with ''Go-Onger'' in ''Shinkenger vs. Go-Onger'', which also starts a new tradition of EarlyBirdCameo by introducing the team from ''Goseiger''.

** Started the trend of ''Metal Hero'' crossovers by doing so with ''Gavan'' (the first Metal Hero) in ''Gokaiger vs. Gavan'', which also introduces the team from ''Go-Busters''. Kenji Ohba's previous roles in ''Battle Fever J'' and ''Denziman'' appear alongside Gavan, as do retired villains from ''Abaranger'', ''Magiranger'', ''Boukenger'', ''Gekiranger'', and ''Go-Onger''.

** A LeaningOnTheFourthWall reference in ''[[Film/SpaceSheriffGavanVsTokusouSentaiDekaranger Gavan vs. Dekaranger]]'' could suggest that ''Akibaranger'' has influence on the prime ''Super Sentai'' universe itself, which is further implied in ''Superhero Senki'' via the Zenkaigers using an Akibaranger Sentai Gear, indicating that ''Akibaranger'' is a world within the ''Zenkaiger'' multiverse.

** ''Toei Hero Next 4: We're a Bounty Hunter Team'' sets itself in the continuity of ''Kyoryuger'', with references made to the Deboss invasion.

** The crossover with ''Kamen Rider Drive'' to promote ''Super Hero Taisen GP'' notably treats ''Ninninger'' as taking place in a separate universe from ''Drive''.

* ''Series/KikaiSentaiZenkaiger'' (2021-2022): Like ''Kamen Rider Decade'', ''Zenkaiger'' uses the concept of TheMultiverse. Like ''Kamen Rider Zi-O'', ''Zenkaiger'' treats all previous seasons as taking place in their own individual worlds, though the extent to which they are separate is currently unclear, though ''Gokaiger'' is seemingly treated as one CrossoverAlternateUniverse for the first 35 seasons, [[spoiler:and a FreezeFrameBonus during the season's endgame implies the existence of another CrossoverAlternateUniverse called Super Sentaitopia that may be the setting of every prior season sans ''Kyuranger'']].

** Introduces the Red Ranger of the next season ''Donbrothers'' in episode 42. Crossed over with ''Kiramager'' in ''Zenkaiger vs. Kiramager vs. Senpaiger'', with the Senpaiger team consisting of Red Rangers from ''Gokaiger'' to ''Ryusoulger''.

** In addition to teaming up Build'' and Ex-Aid with their Legend Rider predecessors, ''Heisei Generations FINAL'' pits the heroes against a MadScientist's AllianceOfAlternates, one of whom is a Foundation X member. Said mad scientist is referenced in the ''Build'' series proper numerous times. The assistant director applied a retcon to Fourze's appearance in this movie, setting it a day before the ''Fourze'' portion of ''Movie War Ultimatum'' to account for continuity issues with the loss of his TransformationTrinket in the latter movie.

** Crossed over with ''Ghost'', ''Drive'', ''Gaim'', and ''Wizard'' in ''Heisei Generations''. The ''Kamen Rider Genm'' miniseries acts as a sequel to ''Heisei Generations'', depicting the '"Ganbarizing'' game as an in-universe game connected to the Legend Rider Gashats. The BigBad of the movie, Dr. Pac-Man, is repeatedly referenced by his real name Michihiko Zaizen as an important character in the backstory of ''Ex-Aid'' as a whole.

* ''Series/KamenRiderBlack'' is, continuity-wise, totally independent of the previous Kamen Rider series. Infact, the protagonist, Kotaro Minami, coins the name himself.

** The Hyper DVD special has Ryuki meeting the unfamiliar Agito, but it was AllJustADream.

* ''Series/KamenRiderDecade'' (2009): This series introduces TheMultiverse, with alternate universe counterparts of each of the first nine Heisei Rider series and the prospect of a MergedReality being endangered WhenDimensionsCollide. From this point onwards, most Rider series, from the original to the present, are said to take place in the same world, with an annual crossover movie between the current series and the previous one.

** Crossed over with ''Decade'' in ''Movie War 2010''.

** Crossed over with ''Double'' in ''Movie War Core''.
** TheMovie hosts the debut of Fourze himself.

** TheMovie hosts the debut of Wizard as a Rider.

** Crossed over with ''Fourze'', ''OOO'', and ''Double'' in ''Movie War Ultimatum''.

* ''Series/KamenRiderDrive'' (2014-15): ''Drive'' features, albeit in a minor capacity, a human terrorist organization known as Neo-Shade, who are said to date back to 2009, alluding to the bad guys from ''G''. Features an EarlyBirdCameo by Ghost in TheMovie as well as the final two episodes, the last of which is called back to early on in ''Ghost'' proper.

** Crossed over with ''Shuriken Sentai Ninninger'' to promote ''Super Hero Taisen GP'' (though the special notably treats ''Drive'' and ''Ninninger'' as being in separate universes). Said movie's sequel miniseries ''Kamen Rider 4'' crosses over with ''Den-O'' and acts as a FullyAbsorbedFinale to ''555''.

* ''Series/KamenRiderAmazons'' (2016, 2017): ''Amazons'' is a streaming series, visually derived from ''Amazon'' but sharing no continuity with it. It is confirmed by [[WordOfGod producer Shinichiro Shirakura]] to take place in an alternate reality to the prime ''Kamen Rider'' universe, though their inclusion in the same multiverse is acknowledged by the appearance of ''Amazons'' characters in ''Chou Super Hero Taisen''. The ''Amazons'' characters also appear in the ''Zi-O'' stage show set after TheMovie's AlternateTimeline, further establishing its place in the multiverse.

** Crossed over with ''Ghost'', ''Drive'', ''Gaim'', and ''Wizard'' in ''Heisei Generations''.

* ''Series/KamenRiderBuild'' (2017-18): Uniquely, ''Build'' sets itself in an AlternateUniverse to the prime ''Kamen Rider'' reality, as seen when it crosses over with ''Ex-Aid'', ''Ghost'', ''Gaim'', ''Fourze'', and ''OOO'' in ''Heisei Generations FINAL'' via dimensional travel to fight a MadScientist's AllianceOfAlternates, one of whom is a Foundation X member. Features an EarlyBirdCameo by Zi-O in TheMovie and a tease of one of ''Zi-O'''s {{Transformation Trinket}}s in the final episode.

** TheMovie was a tribute episode for ''Drive'', as well as "Lost Heisei Riders" i.e. ''Black RX'' which began in the Showa era but finished in the Heisei era, the three films from the 90's, and ''Amazons'', and had a cameo from the protagonists of ''Kamen Norider'', ''G'', and the ''Kuuga'' manga[[note]]WordOfGod claims this movie split into an AlternateTimeline's ending that leads into the ''Final Stage'' show, but its effect on the status quo and narrative is referenced just enough that BroadStrokes versions of its events must have occurred in the series[[/note]].

** Crossed over with ''Ghost'' in the ''Kamen Rider Saber × Ghost'' and ''Kamen Rider Specter × Blades'' specials, the latter ending with a SequelHook that leads into ''Kamen Rider Outsiders''.
** Crossed over with ''Kikai Sentai Zenkaiger'' to promote the ''Superhero Senki'' movie.

** The 20th anniversary reunion movie appears to be set primarily in the continuity of the television series and contradicts the ''Abaranger'' characters' appearances in most other crossovers, but was promoted by a special crossing over with ''Donbrothers''.

** Crossed over with ''Gokaiger'' in ''Go-Busters vs. Gokaiger'', which also introduces the team from ''Kyoryuger''.