Kamen Rider's Cross of Fire

The central theme of the long-running franchise is revealed only in a bonus episode four decades later.

Image source: Kamen Rider Wizard, Episode 53 "Neverending Story"

Preface

Kamen Rider is a superhero TV show by a manga writer Shotaro Ishinomori. It's been airing since 1971, with a hiatus in the 90s. Each season follows individuals who transform into armored warriors of justice and dismantle an evil organization one monster at a time. I have to make an obligatory comparison to Power Rangers, which is an import of Super Sentai, another Ishinomori's show that is in the same genre and airs in Japan together with it. Compared to Sentai, the Riders rarely work in a team, don't have Zords, monsters genuinely are trying to and do kill civilians, and everyone's pasts are a source of mystery.

Kamen Rider Wizard is the 23rd season aired in 2012. Its premise is irrelevant for now. The post-season epilogue is a special two-part crossover. In there, the titular Wizard, Haruto Soma, ends up in some sort of hell dimension ruled by Amadum, where all monsters defeated by the past protagonists end up in, and local children transform into new ones, who Haruto gets protective of. Amadum meanwhile captures past Riders and absorbs their powers, with the argument that he can do that because Riders share a "sin" with the monsters and Riders are "evil" creations. This relation is represented (verbally) by a burning crucifix. When he sends the Riders against Wizard and a boy he's been escorting, they refuse to obey him, and the next year's protagonist, Gaim, appears and steals the powers back to their owners. As Amadum is in disbelief why the Riders would use their "evil" powers to protect "unborn" monsters, the reply is that Riders fight for "freedom" instead of "justice", before he gets obliterated.

Cross of Fire

You Kamen Riders were born in this place. Kamen Riders are nothing more than those who have failed to become true monsters. Wizard was born from the Sabbat, which was supposed to create Phantoms. You, as well, gained magic power by restraining a Phantom within your body. Kamen Riders... They're made from the same stuff as the forces of evil! The power of the Kamen Riders is called the "Cross of Fire". The sign of their sin, in being creations of evil!
— Amadum

The villain's metaphorical power embodies one of the core themes of the franchise. Generally, the protagonist gains his Rider powers through an experiment by the villains for their own long-term goal or is otherwise somehow secretly involved with them. In that regard, the way the protagonist obtained power involves some kind of "sin". However, as summarized by the crossover, Riders subvert the relation in two aspects:

1. Everyone decides who they want to be for themselves and nobody is destined to become a monster. It's often demonstrated that our pasts don't define us. Instead, for the sake of own beliefs, Riders openly reject the source and initial purpose of their powers and use them to protect others. Similarly, Riders reject ideology and temptation of the villains even when threatened, and won't hesitate to sacrifice themselves. While the boy of the episode is set to reincarnate as a monster by that world's rules, he shows an intent to become a Rider himself, ending the episode on an optimistic note.
2. Riders are not glorified monster executioners and don't operate by the needs of the many. They all share the desire to protect the smiles of children, so killing one due to a future threat would be unbecoming of them. Outside of that, they all have individual perspectives on justice and don't mindlessly work for the sake of general safety of humans. Riders exercise empathy, and even if they systematically destroy monsters, they don't have to if possible. In fact, sometimes monsters are conscious enough to ally with the heroes.

In short, the Cross of Fire can possibly symbolize different things:

• Carrying the sins of others and own past upon your shoulders, as per Christian philosophy.
• The crossroad, where one's path in life is always a matter of choice.
• A never-ending clash of good and evil within oneself.

Per-season review

(Note, that below will be spoilers. Also this list may be incomplete and I may recall something later. Could also have more detial on heroic resolve.)

• Kamen Rider (1971-1973)
  • Takeshi Hongo is a biochemistry student and motorcycle enthusiast. Due his high intellect and strength, he gets kidnapped by a terrorist group SHOCKER and is transformed into their cyborg commander. However, before the brainwashing could be complete, he is released by one of SHOCKER's remorseful scientists, who gets assassinated for it. Takeshi dedicates his life to defend civilians from SHOCKER's minions, who are all cyborgs like himself, and eventually crushing it.
  • Hayato Ichimonji is a freelance photographer who gets kidnapped by SHOCKER to be converted into Takeshi's evil counterpart. However, he gets rescued by Takeshi himself, who then leaves Japan and appoints Hayato as his successor.
• Kamen Rider V3 (1973-1974)
  • Shiro Kazami's entire family was killed right in front of him by SHOCKER's successor, Destron, due to witnessing one of their crimes. And he would have been killed too if not for the rescue by the Riders 1 and 2. Despite asking for power to avenge his family, Hongo, Kazami's university senior, has refused. However, Kazami soon ends up fatally injured by Destron, so the Double Riders revive him as a cyborg in a captured Destron lab and share their powers with him. After the three use nearly-suicidal tactics to prevent the destruction of Tokyo, Kazami, compelled by the two's passion, picks up where they've left off.
  • Joji Yuki was a suicidal abandoned child adopted by the leader of Destron, and has served him loyally as his scientist. But he gets framed by a colleague and barely escapes execution. Due to his injuries, he asks to be turned into Riderman in an underground clinic. When he gets defended by V3, he gets an idea to follow him as a double agent in order to prove himself to Destron. However, the leader of Destron confirms that his plans are more destructive than Joji knew, prompting him to sacrifice himself to protect Tokyo.
• Kamen Rider X (1974)
  • Keisuke Jin was a marine explorer, before his family got attacked by the Government of Darkness to steal their technology. His father turns bleeding Keisuke into a cyborg before dying himself. Driven by revenge, he finally discovers that the true puppetmaster of G.O.D. was Dr. Noroi, Keisuke's father's colleague from university, who betrayed him in order to pursue ambitions with cybernetics.
• Kamen Rider Amazon (1974-1975)
  • Daisuke Yamamoto was a wild child living in the Amazon Forest, before he received the GiGi Armlet by the last Inca to safeguard against Gedon. GiGi Armlet and GaGa Armlet (which is in Gedon's possession) are two keys of giving the wielder the ultimate Inca power. Due to not being raised in a civilization, he has mutual distrust in humans, but eventually defends Ritsuko from Gedon even after she asked him to disappear.
• Kamen Rider Stronger (1975)
  • Shigeru Jo baits Black Satan into turning him into a cyborg allegedly for the sake of revenge, then escapes, intending to use the power against them from the start for being involved in his friend's murder.
  • Shigeru is joined by Yuriko Misaki, who became a cyborg similarly, but ended up sacrificing herself.
• Kamen Rider: Skyrider (1979-1980)
  • Hiroshi Tsukuba is a hangglider enthusiast, who looked into an attack by the Neo Shocker, and gets fatally injured and captured during the investigation. But he breaks free mid-conversion and fights against the organization.
• Kamen Rider Super-1 (1980-1981)
  • Kazuya Oki volunteers for cybernization to explore outer space, but the Dogma Kingdom destroys International Space Development Programsoon afterwards. There's not much of a connection here outside of Dogma being cyborgs from space.
• Birth of the Tenth! Gather All Kamen Riders!! (ZX) (1984)
  • Ryo Murasame got captured by the Badan Empire and converted into a cyborg, however due to an accident he regained his memory. Ryo didn't know who to trust and believed Riders to be Badan's agents. After V3 appeared to resolve a misunderstanding, Ryo joins the other 9 riders against Badan.
  • In the SPIRITS manga, Ryo has been Badan's agent for a while before his memories returned. After that, he had trouble proving himself to be on the side of good and believed himself unworthy of the Kamen Rider name.
• Kamen Rider BLACK (1987-1989)
  • Kohtaro Minami and Nobuhiko Akizuki were selected by the Gorgom cult to be potential successors of their leader Creation King, and were converted into cyborgs with infused Kingstones. However, their adopted father has managed to get Kohtaro to escape. When Kohtaro learns of his origins, he leaves Prof. Akizuki to die, but gets a change of heart too late. He becomes devoted into stopping Gorgom, but is reluctant to fight Nobuhiko. He ends accidentally ends up killing him anyway, before going after the leader of Gorgom.
  • In the sequel, revived Nobuhiko manages to come back to his senses. Despite denying his connection to Kohtaro, he ends up sacrificing himself protecting children from the Crisis Empire.
• Shin Kamen Rider: Prologue (1992)
  • Shin Kazamatsuri volunteers to be a subject for medical experiments hoping they'd be of scientific value, however the goal of Institute of Super Science was to create a bio-engineered superior race. Shin struggles keeping his mutant transformation in check and loses all those who are dear to him, while being told to embrace his murderous nature. When his pregnant girlfriend gets killed, Shin regains his humanity and goes against the Institute's mutants. In the end, Shin flees to take care of his child, even if he's being hunted down by the CIA.
• Kamen Rider ZO (1993)
  • Masaru Aso was an assistant of Dr. Mochizuki, who then abducted him and experimented on him to create the ultimate lifeform, using him as reference to create Neonoid. When Dr. Mochizuki's lessons to make his "child" despise humans proved to be too efficient, Dr. Mochizuki realized his mistake and sought Masaru's help. Masaru repeatedly saves Hiroshi, Dr. Mochizuki son, form Neonoid, before destroying it.
• Kamen Rider J (1994)
  • Koji Segawa was resurrected by the Earth Spirits after felling off the cliff while fending against alien Fog Mother's monster. They don't really share a connection.
• Kamen Rider Kuuga (2000-2001)
  • Yusuke Godai ends up in a possession of an ancient belt, which grants him power to destroy the Gurongi Tribe members. Yusuke at first hesitates, but his conviction to protect humans grows. As Kuuga's powers are quite explosive and only get stronger over time, Yusuke makes sure to take the fights away from populated areas. Later it's shown that Kuuga's belt is derived from Gurongi's. In the end, the leader of Gurongi, N-Daguva-Zeba reveals that the purpose of the hunt game wasn't to elect his Gurongi successor, but to turn Yusuke into his successor through the repeated exposure to violence. Yusuke ends up killing Daguva with his bare fists, but despite everything, remains an optimist.
• Kamen Rider Agito (2001-2002)
  • Shoichi Tsugami, Ryo Ashihara, and Kaoru Kino were given their powers by the Prometh, an ancient entity of light, to counter its god-like counterpart, the Overlord Theos, who is said to be the creator of humanity. Shouichi eventually convinces the Overlord that humans aren't trying to usurp him. In some side materials, the Overlord is implied to have created Prometh and Kuuga as well.
• Kamen Rider Ryuki (2002-2003)
  • Shinji Kido picks up Kōichi Sakakibara's belt while investigating a missing persons case for the ORE Journal and becomes Ryuki after trying to fend off a Mirror Monster. Because of this, Shinji becomes a participant of the Rider Fight, an elimination game where the last Rider standing is granted a wish. All belts were created by Shiro Kanzaki by infusing them with captured Mirror Monsters, who repeatedly tries to get Riders to kill each other, so his own representative, Odin, who he has brainwashed, will gain a wish for him. Despite finding Shiro's motives sympathetic, Shinji is determined to seal off the Mirror World as uninvolved people fall pray to Mirror Monsters. After everyone dies, Shiro realizes his mistake and resets time.
  • Masashi Sudo, Jun Shibaura, Takeshi Asakura and Mitsuru Sano followed their darker impulses during the event. Hideyuki Kagawa and Hajime Nakamura forced their way in into Rider Fight by reverse-engineering Shiro's research for the sake of revenge. Despite having personal agenda for joining the Rider Fight, Ren Akiyama, Shuichi Kitaoka, Goro Yura, Miyuki Tezuka, Satoru Tojo eventually join Shinji's cause.
• Kamen Rider 555 (2003-2004)
  • Takumi Inui picks up the stolen Rider Gear, created by the Orphnoch to be used by their executives. Takumi ends up revealed to be an Orphnoch himself, dying and reviving after a fire accident, who decided to use this power to protect Ryusei School. However, he ends up having his memories confused. Despite his anti-social behavior and trying to avoid connections, Takumi grows to empathize with the Orphnoch and learns that it's fine to bond with others.
  • Yuji Kiba died in a car accident and is revived as an Orphnoch. After calming down after his initial murderous rampage, Smart Brain has attempted to scout him to pit against humanity, but he refused. Believing that Inui is there to eliminate him, he battle him many times before realizing that both of them want humans and Orphnoch to co-exist. Due to manipulations by Masato Kusaka and Saeko Kageyama, Kiba abandons his faith in humanity and usurps Smart Brain, but after another encounter with Takumi, Kiba chooses to sacrifice himself during the battle with Arch Orphonoch.
• Kamen Rider Blade (2004-2005)
  • Kazuma Kenzaki gets chosen as an agent for Board Of Archaeological Research Department, and is given the Buckle to hunt the Undead. Later it turns out Board were responsible for releasing the Undead in the first place. Blade's system is additionally powered by the captured Undead. This became a concern when Kazuma slowly became turning into an Undead himself. But this comes in handy, as the Stone of Sealing would get triggered if all Undead are defeated, so Kazuma becoming the Joker Undead becomes the best case scenario even if he can't live a normal life.
  • Hajime Aikawa's true identity is Joker Undead, the judge of the event. The humanity is said to be the descendants of the Human Undead, who Hajime takes the appearance of and learns much from. Not wanting the humanity to be erased, he fights both the Undead and the Board's higher-ups, and in the end nearly ends up sacrificing himself to stop the Stone of Sealing.
  • Mutsuki Kamijo is a school student who gets kidnapped and possessed by the Spider Undead to hunt down the rest. Even without Undead's influence, Mutsuki is extremely competitive, treats hunting the Undead like a game, and gets jealous of Kazami for his superior powers. He eventually snaps out of it, and relates the trauma of others with his own.
• Kamen Rider Hibiki (2005-2006)
  • Hitoshi Hidaka and other Oni Riders are trained to fight Makamou by turning into demon, and have a risk of goin berserk.
• Kamen Rider Kabuto (2006-2007)
  • Soji Tendo "steals" Kabuto Zecter from ZECT and kills Worms without their supervision, even if their goals are the same. As it turns out, ZECT's higher-ups are Worms themselves, who have developed Zecters to fight the other faction, as they would interfere with their takeover of humanity. Soji doesn't mind Worms that aren't hostile. Soji's real name is Soji Kusakabe, his parents were killed and replaced by Worms, but before he could take revenge on them, everyone got in the center of the Shibuya Meteor Strike. After promising to take care of their amnesiac Worm daughter, the two Worms have given Soji his Rider Belt.
  • Dark Kabuto is a human turned into a Worm by ZECT, who is given Soji's appearance and memories. After being sent to defeat the original, he started to prioritize protecting Hiyori. After multiple clashes with Kabuto, Dark Kabuto sacrifices himself in battle against ZECT, leaving Hiyori again in Soji's care.
• Kamen Rider Den-O (2007-2008)
  • Ryotaro Nogami finds a Rider Pass and is made combat time-traveling Imagin. As a Singularity Point, he remembers changes to the past and is immune to the effects of a possession, so he forms contract with some Imagin to fight using his body.
  • Yuto Sakurai has formed a contract with an Imagin Deneb, but his transformations into Zeronos have a cost of his future self's presence in time, to the point where he got erased, twice.
• Kamen Rider Kiva (2008-2009)
  • Wataru Kurenai is the son of Fangire Queen, raised by Otoya. Due to his mixed heritage, he is treated as a threat by both the Fangire and humans, and he is reclusive in general. When he is turned berserk by Bishop, turns isolated again to avoid harming anyone, but finds resolve again from the memory of his parents. In the end Wataru manages to redeem Taiga from his genocidal plans.
  • Keisuke Nago is a Fangire hunter, who makas no exception for Kiva despite him helping humans. As Keisuke is unable to defeat Kiva, his sanity becomes unstable. However, when he learns of Wataru's identity, he becomes a mentor for the boy and protected him from other hunters, and even was there for him during his depression.
  • Otoya Kurenai is a womanizer who tries to swoo Yuri and defended her from the werewolf Jiro, until he befriended him in rivalry and united against Fangire King. Later, Otoya romanced Maya, despite knowing that she's a Fangire and the fiance of the Fangire King. Thanks to Otoya's kindness, Maya has sided with humans and turned into hiding. Otoya holds a duel against Fangire King, transforming into Dark Kiva despite knowing that as a human, he wouldn't survive the transformation.
  • Taiga Nobori is the heir of the Fangire King, who is manipulated by Bishop to unite Fangires against humans and taking Mio as his bribe. When Mio tried to kill him and is killed by Bishop, Taiga was driven with rage. However, Wataru manages to bond with him over their family, and Taiga eventually agrees that humans and Fangires can co-exist, killing Bishop along with his revived father.
• Kamen Rider G (2009)
  • Goro was kidnapped by Shade and was brainwashed into one of their cyborgs. But upon seeing his girlfriend Eri as a hostage, he regains his memories and turns against Shade.
• Kamen Rider Decade (2009)
  • Tsukasa Kadoya finds the Decadriver and traverses the parallel worlds in search of his missing memories. Despite the constant reminders that he is meant to destroy other Riders, he instead bonds with them. At one point Tsukasa enters a world ruled by Dark Riders, and is offered luxury if he stays, but he instead kills the villains. As it turns out, Tsukasa was the leader of Dai-Shocker who intended to conquer the universe with this power. When Tsukasa rejects his past following this revelation, Dai-Shocker turn on him.
  • Daiki Kaito got exiled from his world after his brother got brainwashed by Fourteen. He eventually steals the Diendriver from Dai-Shocker, which was meant to be the prototype version of the Decadriver.
• Kamen Rider Double (2009-2010)
  • Shotaro Hidari was Sokichi Narumi's detective sidekick. During an investigation of Museum's facility, they are asked to escort Philip, who has created the Gaia Memories and Doubledriver. Shotaro refuses, but Narumi teaches him that all Futo citizens deserve protection. Marumi ends up murdered by Saeko Sonozaki, but Philip transforms along with Shotaro and escapes. Shotaro works with Philip to destroy the remaining incomplete Gaia Memories in Museum's possession, as they harm Futo. His love for the city sparked the redemption from Kirihiko Sudo, who gets killed by Saeko for betrayal.
  • Philip, Shotaro's partner, is revealed to be amnesiac Raito Sonozaki, the heir of the Museum mafia. When he fell into the well of Gaia as a child, he giant knowledge of all concepts on Earth, represented by a mental library but at a loss of his memories. Museum has kept him in isolation with a new identity of a teen scientist, until his mother asked Narumi to break him out. Upon this revelation, Philip reaffirms that he feels no bonds with the Sonozaki family and stays with Shotaro, however he does defend his sister Wakana from his famil's darkness.
• Kamen Rider OOO (2010-2011)
  • Eiji Hino uses Core Medals, which were created by the Ancient King as a fuel for Greeed as a step for world domination, but was killed by them. In present time, Ankh Greeed sides with Eiji against other Greeed. Core Medals represent desire of humans and are sought by Greeed to become complete, but have some risks when used by Eiji. After being given purple Medals by Kiyoto Maki, Eiji becomes a Greeed himself. Eiji, who generally lacks a desire, gains an ambition to protect humans, but it doesn't slow down the corruption. Ankh sacrifices himself in the final battle, destroying all Core Medals and restoring Eiji to normal.
• Kamen Rider Fourze (2011-2012)
  • Gentaro Kisaragi uses Astroswitches to give himself special abilities. Conversely, the Horoscopes are giving away Zodiarts Switches to the students that give them monstrous powers, in hopes to find someone powerful enough to become one of them. As it turns out, the Astroswitches and Zodiarts Switches are attempts to reverse-engineer the Core Switch, an artifact left by the aliens. When Mitsuaki Gamou believed that 12 Horoscopes Switches would be enough to establish contact with the Presenters, Fourze's 40 Astroswitches have resonated with his sense of friendship more strongly. The Core Switch itself got turned into Kengo Utahoshi, who ended becoming Gentaro's friend. In the end, Gentaro manages to redeem even Gamou, who sacrifices himself to close the black hole of his own creation.
• Kamen Rider Wizard (2012-2013)
  • Haruto Soma gained his power when the White Magician has rescued him from a sacrificial ritual Sabbath operated by Wiseman. Thanks to the power of the incomplete Dragon Phantom within him, Haruto prevents Phantoms from creating more of themselves. As it turns out, White Magician and Wiseman are two aliases of the same person, Sou Fueki, who is gathering Phantoms to start another Sabbath on a larger scale for the sake of his wish. Despite understanding his desire to revive his daughter, Haruto defeats him. Sou ends up killed by Gremlin, who in parallel to Haruto, turns out to not be a Phantom, but a serial killer who suppressed his Phantom during the first Sabbath and has been using a monster transformation to get the Philosopher Stone for himself.
• Kamen Rider Gaim (2013-2014)
  • Kouta Kazuraba and others are gifted Sengoku Drivers by the Yggdrasill Corporation, with the secret purpose of raising their compatibility with the Helheim Forest and prototyping superior Drivers for themselves. The Helheim Forest encroaches upon Earth, and the Yggdrasill Corporation believes the only way for humanity to survive is to adapt to it, with the belt serving as a way to extract nutrition from the otherwise poisonous Helheim Fruits, which were the basis for the Lockseeds. At one point Kouta has a moment of despair when he learns that one of the Inves he killed was one of his acquaintances after a mutation. Despite the constant reminders to leave humans to the survival of the fittest, Kouta becomes an Overlord and drives the Helheim Forest away to a different planet.
• Kamen Rider Drive (2014-2015)
  • Shinnosuke Tomari's Drive technology uses Core Driviar, a gravity engine developed by Krim Steinbelt. Krim partner Tenjuro Banno used the same engine to create Roidmudes, who he planned to take over the world with, however his abusive tendencies caused him to rebel against him and treat humanity as their enemy. Roidmudes later derive Viral Cores from Shift Cars. While Shinnosuke systematically hunts down Roidmudes, he becomes more empathetic to their plight.
  • Go Shijima arrives to Japan to hunt the Roidmudes, but to also look for his father, Tenjuro Banno. At one point Go mentions that Kamen Riders are essentially monsters due to their power. Go later infuses himself with Chase's Viral Core in order to bring an end to revived Banno.
  • Chase is an android created by Krim Steinbelt as a prototype for Drive, and was sent after the Roidmudes after they rebelled. However, he was defeated by Heart Roidmude and his memory was wiped out, becoming the enemy's enforcer. Over time, he comes to learn that humans aren't inherently abusive, and discovers that he protected Kiriko as ProtoDrive. After joining with Special Investigation Unit, he helps his comrades Heart, Medic and Brain to see humanity is a positive light, before all perished in battle against Sigma Circular.
• Kamen Rider Ghost (2015-2016)
  • Takeru Tenkuji is revived in a ghost body by Magistrate Edith to combat the Gamma invasion. Both Takeru and the Gamma use the Eyecons as the source of their powers and the hosts of their souls. Later it's explained that Gamma are humans who some time ago have decided to live in a parallel dimension, and use holographic bodies to operate on Earth, but since then resorted to sacrificing humans for energy. Takeru's empathy helps to redeem the Gamma's empire and allow Adel to admit to his crimes before he was killed by the Gammaizers.
  • Alain is a prince of Gamma who serves the ambitions of his father Adonis. However, Adel has usurped the throne and accused Alain of regicide, forcing Alain to live in the human world and eventually bond with Takeru and see the infinite potential of humans. His actions manage to pull other Gamma to his side.
• Kamen Rider Amazons (2016-2018)
  • Haruka Mizusawa was created by the Nozama Pharmacy after experiments with Amazon Cells. He gets raised by Reika Mizusawa as a human and kept him isolated. Years later, Haruka's instincts take over, he transforms and tries to cannibalizes another Amazon. After Jin explains everything, Haruka agrees to hunt down Amazons while learning to control his hunger. But when he learns that Nozama Pharmacy plans to exterminate all Amazons regardless of his allegiance, Haruka then switches to defending Amazons who are friendly to humans.
  • Chihiro is Jin's son and a natural-born Amazon. Young Chihiro accidentally eats own mother and forgets about it. He was captured by 4C, but he manages to escape. He befriends Hiroki Nagase, who proposes Chihiro to hunt down Amazons for fame. Chihiro ends up recaptured by 4C, and partnered with Crow Amazon, who he helps to grow more emphatic. It's later revealed that mutations in the seasons were caused by Chihiro's severed arm polluting the water source, something he is not okay after finding out. Chihiro fails to control his instincts and kills the 4C, then asks Jin and Haruka to kill him so he wouldn't grow even stronger.
• Kamen Rider Ex-Aid (2016-2017)
  • Emu Hojo uses gear that was developed by Genm Corp's Kuroto Dan, who turns out to be the mastermind behind the Bugster infection. Additionally, Emu was the patient zero and the progenitor of the Bugster virus, and also designed the Rider gear as a kid, something young Kuroto took offense with. The prototype games that spawned the Bugsters are later converted into Rider Gashat to capture them in. During his job, Emu finds Bugsters who are friendly to humans, but are threatened. During the confrontation with Parad, Emu threatens to erase him permanently, drilling into him that unlike the Bugsters, humans have only one life. When the true president of Genm Corp, Masamune Dan, reveals his plan to trap humanity in the digital world, Emu rejects it.
• Kamen Rider Build (2017-2018)
  • Sento Kiryu's Fullbottles system is powered by Nebula Gas, the same compound used by Faust to create Smash. Later, Sento is revealed to be the amnesiac identity of Takumi Katsuragi, the "Devil Scientist" who worked with alien Evolt, while planning to sabotage him. Evolto has erased Takumi's memories and kept a close eye on him as he grew stronger, while Sento then got affiliated with Touto Institute. Upon discovering his origin, Sento treats Takumi as a separate person, even if respectfully, vows to destroy Evolt at all cost, even gambiting with own life.
  • Ryuga Banjo is a boxer who got framed for Takumi Katsuragi's murder. He was captured to be experimented on by Faust, but escapes and partners with Sento. Later, it turns out Ryuga was conceived when Evolt impregnated a woman and has been under surveillance, but Ryuga is apathetic to his alien blood, determined to fight for love and peace. After he and Sento were possessed by Evolt, Ryuga helped Takumi to recover his memories as Sento.
  • Kazumi Sawatari was a farm owner before the Sky Wall Disaster rendered the land infertile. He volunteers to be enhanced by Faust and joins Hokuto's military forces for the prosperity of his country. However, after losing to Ryuga, he joins Sento's side.
  • Gentoku Himuro is the son of the Prime Minister of Touto and an aspiring politician himself. After being appointed as the director of Touto Institute, he worked with Takumi Katsuragi and Evolt to found Faust. Due to failures of his own plans in comparison to Evolt's, and after being captured by Seito, Gentoku was unsure what is he doing. When his father died in his armed and asked to protect Japan, Gentoku reluctantly joins Sento's side.
• Kamen Rider Zi-O (2018-2019)
  • Sougo Tokiwa always had a dream of becoming the king of everything, believing that he'll be the most beloved ruler. However, he is told that in the future he becomes the Demon King Oma Zi-O and wipes out most of humanity. Despite the constant notion that his future is inevitable, Sougo works to undo the corruption by the conspiracy from the future. As Sougo uses Ridewatches, Time Jackers implant Anotherwatches into victims. Sougo ends up becoming Oma Zi-O anyway, but cancels his transformation when it counted thanks to the bonds he made.
  • Rento Makina is an android from the alternative future, from an world where Earth is conquered by the Humanoise. However, after Rento befirends a human, he rebels against the Humanoise.
• Kamen Rider Zero-One (2019-2020)
  • Aruto Hiden is the newly appointed CEO of Hiden Intelligence, whose job is to sell android Humagear as assistants to humanity. However, Humagear get corrupted by MBJR, by converting Progrisekeys into Zetsumerisekeys. Later it turns out that MBJR answer to Ark, Hiden Intelligence's prototype satellite, which was in turn corrupted by Gai Amatsu. Despite the difficulties, Aruto is determined that Humagear and humans can co-exist. Aruto's compassion helps everyone in MBJR exept for Horobi to side with humans against Ark. Near the end, Aruto embraces Ark's powers and tries to destroy Horobi, but manages to get a change of heart at the last moment.
• Kamen Rider Saber (2020-2021)
  • Touma Kamiyama uses Wonder Ride Books, which are derivatives of the Almighty Book, just like Megid's Alter Ride Books. As it turns out, as a child Touma has befriended Luna, a living embodiment of the Wonder World, explaining why villains are interested in Touma. Later it turns out the leader of Sword of Logos, Isaac, has became a nihilist and has been working with Megid to reconstruct the Almighty Book, which would allow him to control the world. Despite being labeled a traitor, Touma works his way out to befriend other swordsmen and stop Megid and Isaac.
  • Sophia turns out to be an artificial lifeform created by the Sword of Logos based on Luna. Isaac planned to use her to work with Almighty Book once its complete for his evil plan, in case he fails to secure Luna. Sophia is terrified of Isaac's treachery and works with Touma to oppose him.
• Kamen Rider Revice (2021-2022)
  • Ikki Igarashi has formed a contract with Vice, a demon, in order to stop Deadmans, an cult of demons, who also use Vistamps. Later it turns out Ikki and Daiji have high affinity with demons because their father Genta, who was infused with cells of Giff, the leader of Deadmans.
• Kamen Rider Geats (2022-2023)
  • Ace Ukiyo along with other Riders have entered a deadly game show organized by Desire Grand Prix as participants. Ace himself is also not an original, but a reincarnation of various Aces who have entered the tournament, with the father of the original also being a champion of Desire Grand Prix 2000 years ago.
• Kamen Rider Gotchard (2023-2024)
  • Houtaro Ichinose's powers come from the Philosopher's Stone, which was used by the Dark King in the past. Gigist, the present Dark King, is the one who created Chemies, which gives Riders and Monsters their abilities.
• Kamen Rider Gavv (2024-2025)
  • Shoma Inoue is a Granute hybrid, and a relative of the enmy leader.

Conclusion

As we can see, heroic spirit is one of the most important aspects in the franchise's narrative. While the connection is brought up only in one episode, it remains a crucial bridge that relates to each series' main message.

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