Monster / Kamen Rider

"He is a monster, far worse than the Roidmudes you despise. The marathon of torture that man inflicted upon me...It has been burned into my memory..."
Heart, on Professor Tenjuro Banno, to Banno's son Go(u) Shijima, Kamen Rider Drive, "Why Are the Two Scientists in a Conflict?"

Kamen Rider has several heinous villains.

Kamen Rider
  • There’s a reason why Colonel Bakarashin Iinodevitch Zol continues to be the franchise’s definitive monster to this day. After serving as a Nazi officer in World War II, Zol joins Shocker where he gains a reputation for wreaking havoc in the Middle East. He quickly lives up to this reputation when he’s transferred to Japan to deal with Kamen Rider Nigo. He fails to show any sense of shame for his crimes, ranging from brainwashing children into becoming Shocker guerrilla soldiers to using Wolfsbane to gas attack Goro’s town. Colonel Zol is also a horrible boss to his men. Case in point: Zol praises a revived Egyptus, a mummy kaijin that can incinerate victims, for testing his abilities on (and ultimately killing) one of his mooks. The sequel series Kamen Rider V3 only adds to his crimes. Together with Doctor G, a revived Zol plans to initiate Operation: Japan Annihilation, which involves unleashing a toxic gas in Hokkaido to kill innocents. Zol also does not care about fellow Shocker and Destron officers at all, as seen when he tries to have fellow Destron officer Ambassador Hell executed for failing to defeat Kamen Rider V3.

Kamen Rider V3
  • Marshal Armor, AKA Zariganna, is the fourth and final Destron Commander. When he assumes command of Destron, his first act is to plant evidence against their head scientist, Jo(u)ji Yuki, whom he views as a threat, and execute him via acid pit. Knowing the man values his hands for his work, Armor begins the execution by burning one off first. From there, Armor launches a number of deadly schemes, including attempting to cover Tokyo in nerve gas, kidnapping children for slave labor, and unleashing Vampire-Chameleon on more children to feed off their blood. When Vampire-Chameleon kills a pair of his own men, Armor coldly remarks that if they weren't so weak they wouldn't have died. When ordered by the Destron Leader to launch a nuclear assault on Tokyo, Armor kidnaps a scientist's family to force him to work on the weapon. When he frees the heroes, Armor has him killed, and hangs his corpse outside the Destron base as a warning to all who would defy him.

Kamen Rider Kuuga
  • N-Daguva-Zeba is the lord of the Gurongi and the Ur-CM of the Heisei era. An Ax-Crazy Blood Knight who absolutely despises the lowly and weak, Daguva doesn’t care about any human or Gurongi lives and is willing to use any means necessary to make humanity as violent and hateful as he. Upon being reawaked from Kuuga’s sarcophagus, he releases the 200 Gurongi and murders the archaeologists, thereby kicking off the series. After his escape, he restarts the Gegeru, a game where Gurongi hunt humans with set rules based on their tribe's social status, and kills 152 of his own kind in Nagano. He then reveals himself to the public by killing Zu-Gooma-Gu for using his armor before resurfacing under the guise of a white-suited teenager with an aura as he unleashes heavy rain in Japan. After Yusuke Godai (Kamen Rider Kuuga) defeats Gadoru, Daguva ambushes Yusuke, mercilessly beats him up, and incinerates numerous people in his wake as he leaves Yusuke behind. After continuing his systematic genocide, he meets Yusuke in Mount Kuro where they have their final fight. There, Daguva finally dies, laughing to the very end hoping that Yusuke would be corrupted by violent hatred.
  • Years after he blighted television screens in Japan, Go-Jaraji-Da (the Porcupine Gurongi) still stands as the standard to which other kaijin-of-the-week in Kamen Rider are compared to. Jaraji uses his upper-class privileges to choose the 90 teenage boys in Midorikawa High School's 10th grade as his targets for his game. Using super speed and poisonous darts that kills his victims from encephalitis within four days, Jaraji terrorizes and poisons all but one of his targets, condemning many of his victims to slow, brutal deaths and drives others to suicide. As those who commit suicide do not count to his Gegeru, Jaraji compensates by killing high-school boys belonging to other grades and numerous policemen. Most of the other Gurongi are either required to participate in the Gegeru or merely see the Gegeru as a necessary duty. Jaraji, on the other hand, commits his crimes precisely because he enjoys himself watching living beings suffer and coldly admits this to a family before closing in on one of his targets. It's no wonder Yusuke Godai snapped and killed Jaraji so savagely.

Kamen Rider Ryuki
  • Takeshi Asakura/Kamen Rider Ouja is a psychopath that is drawn to violence and wishes to perpetuate it. Not only does he rack up the highest body count amongst the Riders, who are pitted in a battle to the death where There Can Be Only One, but he's also responsible for the murder of an innocent woman, who turns out to be Kamen Rider Femme's sister, thus making getting revenge her reason for entering into the Rider Battle. To top it all off, he kills his own estranged brother by feeding the latter to his Contract Monster, Venosnaker... after revealing that he was the one who set the fire which burned down their home, killed their parents, and separated them during their childhood in the first place.

Kamen Rider Blade
  • Hiroshi Tennoji, the series' true Big Bad, absolutely reeks of obsession for self-preservation and world domination by any means necessary. As the head of BOARD, he creates the Battle Fight by releasing the Undead and manipulating his contracted Kamen Riders to take them out. As the battle progressed, he invented the Trials and the Titan Undead, all so he could buy himself time to create Kerberos, an artificial Undead with DNA from all 53 Undead that could surpass the Black Joker itself. Tennoji's invention kills the entire BOARD staff upon being born from the Stone of Sealing before he seals the artificial Undead to create a new Change Card. He uses the card to transform into Kerberos II before revealing his dream: to create a new world order with himself as its ruler. It takes all four Riders (with Blade in his King Form and Garren in his Jack form) to stop Tennoji once and for all.
  • Isaka, aka the Peacock Undead, exemplifies how low Manipulative Bastards can go. As the first Category Jack Undead, he designed Rider System 3, a belt that allows the user to transform into Kamen Rider Leangle. Unfortunately, that same belt requires using an improperly sealed Ace card that contains the Spider Undead, meaning that the Undead would mentally enslave its user (as later seen with Mutsuki). After designing the corrupted Rider System, he brainwashed many people that he was going to use as expendable slaves to create his "Ultimate Rider". When this plan failed, Isaka turns his attention to Sakuya Tachibana (Kamen Rider Garren) and attempts to retrieve him as a prototype user. Isaka knows about Tachibana's subconscious fear and takes advantage of it to curbstomp him. Isaka tricks his defeated opponent to getting addicted to Schuld Ketsner seaweed, lying that the aggression-inducing plant would eliminate fear. When Sayoko notices her lover's addiction, Isaka smugly kills her for attempting to clean up her lover. Upon learning about Sayoko's death, Tachibana loses his subconscious fear and eventually gives the bastard exactly what he deserves.

Kamen Rider Kiva
  • The Lion Fangire, also known as Rook, is an Ax-Crazy, merciless, and easily bored Sociopath who treats the lives of humans and monsters alike as a game. Twenty years before Wataru becomes Kamen Rider Kiva, Rook murdered Yuri Aso's mother so traumatically that Yuri swore vengeance on all Fangires (including Wataru's mother Maya). He also was single-handedly responsible for driving the Wolfen race to near-extinction, leaving Jiro as the sole survivor of his genocidal rampage. As the flashbacks progress, Rook devises his personal game to combat boredom called the "Time Play," in which he hunts and eats a select group of people within a time limit. If he succeeds in killing the intended number of people, he rewards himself with ice cream; fail and he self-punishes himself with electric shocks. His already suspect sanity gets even worse when he reawakens and regains his memories in 2008. He proposes a new game which would have him do good deeds before getting himself killed not out of a change of heart but from boredom from constantly playing the "Time Play" game.
  • The Bat Fangire, more commonly known as the 1986 King, is a ruthless tyrant who fails to understand the concept of love. As the original lord of all Fangires, the King uses his position to annihilate the Merman and Franken races, as well as persecute Jiro (the last Wolfen). When he finds out that his wife Maya has fallen in love with Otoya Kurenai (the original Kamen Rider Ixa), the King offers Jiro, as well as the sole surviving Merman and Franken (Ramon and Riki respectively), a chance to avoid extermination in exchange for killing Otoya. When they choose to escape instead, the King forcibly transforms them into Empathic Weapons. He then kidnaps Otoya and attempts to use his life energy to feed Castle Doran, the King's living castle. When Otoya escapes, the King exposes his lack of any sense of love toward his own wife by using the life of his own son, Taiga Nobori (Kamen Rider Saga), as blackmail to prevent her from seeing Otoya again. This disgusts Kivat-bat the 2nd, who is meant to be the King's loyal Transformation Trinket, so much that he offers Otoya a chance to become Kamen Rider Dark Kiva in order to destroy the King.
  • The Rhino Fangire was rather nasty. He tricks young people into believing he'll help make their dreams come true to lure them in so he can steal their life force. After killing them, he takes an item from them that relates to their dream as a trophy to put in his "Dream Graveyard". His choice of prey is based solely on a love for crushing the dreams of young people and nothing else. Even Wataru, who had generally tried to find the good in everyone, even Fangires, found his actions unforgivable.

Kamen Rider Double
  • Doctor Shinkuro Isaka, the Weather Dopant, killed Terui's family, modifies Gaia Memories to kill their users so that he can take their power for himself, and is able to use Gaia Memories via direct insertion without any ill effects (typically, repeated use of Gaia Memories via direct insertion warps the user's mind, which shows that Isaka didn't have far to fall). He then tries to get Saeko to kill her own father and take control of the Museum.
  • W Returns: Eternal: Dr. Prospect/Eyes Dopant is a man who kidnapped people from all over the world to make them into, in his own words, "lab rats" for his Quark Project by giving them Psychic Powers. When he arrives on the scene, every one of these people with psychic powers are utterly terrified of him, showing how horrifically he treated them. Even worse is his Heaven's Fall plan, which was so vile that Utopia Dopant considered it a brutal act. Prospect would blast the area with an electric pulse and that would kill anyone that had not lived up to his standards for the project, referring to this as "cleaning out the test pool". When Daido foils his plan, it is revealed that was merciful compared to what happens if they try to escape him. The eyes he implanted on them to watch them are used to kill them when they leave his compound. Dr. Prospect then laughs his head off at the fact he'd just slaughtered a village of innocent people while Katsumi is in shock over the massacre of the village he'd tried to save. His actions are so horrific that it drove Katsumi insane.

Kamen Rider OOO: While the show took a balanced look at greed and showed it did not need to be bad, these three demonstrate the worst elements of it:
  • Kazari, the Feline Greeed, is The Chessmaster responsible for many atrocities throughout the series. Of the five original Greeed, he has by far the most horrific way of making YummyMISC. INFO  by implanting them within their host and controlling the host like a puppet, in some cases while the host is conscious the entire time. After a while it consumes and traps them inside while they are fully aware of what is happening to them. Kazari's actions in the series proper are worse. He used his own compatriots Mezool and Gamel as guinea pigs to see what would happen if a Greeed absorbed Core Medals that weren't their own, and was unfazed by there deaths, using this opportunity to absorb their Cores and become stronger. He later raised Lost Ankh as his own personal brainwashed warrior and helps Dr. Maki in trying to destroy the world. Sadistic and uncaring, even his own kind despise him for what he is.
  • The aforementioned Doctor Kiyoto Maki, the Dragon-in-Chief to Kazari, is a prime example of what happens when antisocial behavior goes off the deep end. Before the day of his sister Hitomi's wedding, Maki burns his sister to death in her sleep just because she was going to abandon him. He then represses these memories and helps a Mad Bomber hosting Mezool's Yummy carry out attacks just to see the Yummy grow, not caring who dies in the process. When the swarm of Yummy hatches, he remorselessly locks his workers inside with them and watches the Yummy slaughter his colleagues. When he teams up with Kazari, his memories of Hitomi resurface, driving him to destroy the world. True to his personal philosophy that "something's true value is only known when it ends", he absorbs five Purple Core Medals to begin transforming into a Greeed himself, the Dinosaur Greeed. Because the core medals make up the essence of a Greeed and give its user Greeed powers, Maki spawns Yummy that are omnicidal, with Maki finding their rampages to be merely "interesting". He also has no sense of loyalty to his allies, as Kazari learned the hard way when Maki impales him and rips all his cores out of him. Near the climax of the series, Maki gives two of his own Cores to Eiji (Kamen Rider OOO) solely to accelerate Eiji's greeedification and tosses the remaining Core Medals from the other Greeed into Uva to forcibly set his ultimate plan of destroying the world into motion.
  • The original Kamen Rider OOO and the Greater-Scope Villain of the entire series was an ancient king of a lost civilization who wanted power over anything else. He had three alchemists and Gara create five sentient creatures, the aforementioned Greeed, for the sole purpose of killing them off to reach his goal of becoming an immortal god. After the alchemists and Gara succeeded, he betrayed them and turned them into cell medals, with Gara still being conscious in this state. He then stole the core medals from the Greeed even though that would kill them over time. He used this power to take over a large portion of Europe and was well on the way to taking over the world. The prequel novel by Nobuhiro Mouri expands on his actions and shows that he cloned himself to attack neighboring countries; burned down villages that opposed him; invaded enemy camps using subterfuge; and used earthquakes and tsunamis to wipe out the Spanish Armada. After Ankh betrays the other Greeed by working with him, he double-crosses Ankh and stabs him in the back for his Core Medals and causes all the Greeed to be sealed away just so he could have the medals for himself.

Kamen Rider Fourze
  • Tatsumori Yamada/Aries Zodiarts was transferred around the same time Ryusei came to Amanogawa, and in that amount of time, he's the undisputed king of Subaruboshi high. He forces the whole school (teachers included) in his little play like world where everyone is graded on their performances. If they did bad jobs, he would them into a permanent sleep. He even makes a Deal with the Devil with Meteor, reviving Jiro if Meteor killed Fourze and he follows up on his deal. Then he decides to do a play called "School War" which has the Kamen Rider Club kill students before deciding to reverse the roles and have the Kamen Rider Club being tied up to poles and killed. Thankfully, Gentaro is revived and kicks his ass so badly that he is sent into a coma.
  • Rem Kannagi, the Big Bad of Movie War Megamax wants to use the power of the Astro Switches and the Core Medals from the future to become an all powerful being known as the Super Galaxy King and will do absolutely anything to accomplish this, and taking a sick glee in rubbing his advantage in the faces of his enemies whenever he gets the chance. He essentially kills Gentaro's girlfriend, Nadeshiko for the SOLU she's composed of, and then rubs that fact in Gentaro's face. He also had no problem killing anyone that gets in his way without an ounce of remorse, or creating clones of all the Greeed and Sonozaki Dopants for his own evil purposes. He gets his in the end though, after being Double Rider Kicked by Fourze Double Rocket States and OOO Super TaToBa Combo, sending him into the path of his own shuttle that runs him over.

Kamen Rider Wizard: Even in a series where the villains forcefully tried to turn humans into phantoms by making them give into despair, a select few stand out as much worse than the others:
  • Phoenix stands out even among the Phantoms as a complete psychopath who will go to horrific lengths in order to make Gates to create more phantoms. His methods involve beating a lady just so her child would give into despair; he later breaks into a hospital and randomly attacks innocent people, including patients who have no connection to the Victim of the Week at all. Even his compatriot Medusa is frightened of his brutal tendencies since he has gone as far as to kill a Gate before the corresponding Phantom can manifest. His sadistic tendencies are so fierce that his boss Wiseman kept him to an observatory role at first rather than being allowed to directly intervene for fear of him going out of control.
  • Sora Takigawa/Gremlin was once a Serial Killer who started to kill woman with white dresses and black hair after one dumped him, with this woman his first victim. He was later kidnapped to be made to give into despair and become a phantom. When a Human gives into despair and becomes a Phantom they normally lose almost all aspects of their former personality, but Gremlin still retains Sora's desire to murder women and his sadistic and childish personality. It originally seemed like he had noble intentions in protecting the Gate, but this was revealed to be an act; he intended to indulge in his host's former taste and attempts to kill her for the sheer fun of it. He also makes no qualms about the fact that all the women he murdered were just for his own sick pleasure or Disproportionate Retribution.

Kamen Rider Gaim

In a series that takes the franchise back to its Darker and Edgier roots, there are two heinous villains who cross the ultimate lines:

  • Professor Ryoma Sengoku/Kamen Rider Duke, the creator of most Armored Rider gears, is a sociopathic Mad Scientist who initially works as a researcher in the Yggdrasill Corporation's R&D division, and has no concern about the lives of others except for himself, his research, and those he deems an extension of himself, his goal is to grasp the Forbidden Fruit by any means necessarily in order to become a god. Being a backstabber, he cares not for his allies, simply using them as a means to an end and disposing of them when they become unnecessary. His experiments on the Helheim Forest has caused damage, to the point where the world is on the brink of destruction. He also is a Dirty Coward who uses cheap tactics on his opponents, as is shown when he hacks his own Genesis Driver and then whenever he faces another Genesis Driver users, he uses a kill switch to disable his opponent's Genesis Drivers so they cannot fight back against him. Once the Overlords were dealt with, Ryoma has successfully manipulated Mitsuzane Kureshima into almost killing Kouta Kazuraba by providing him the life-threatening Yomotsuheguri Lockseed before he revealed to Mitsuzane that his promise to save Mai Takatsukasa's life was a lie, as he cold-bloodedly murders her by dissecting the Forbidden Fruit, fused into her heart, from her, just to obtain the Fruit for himself.
  • The Overlord Inves, except for Roshuo, were definitely no saints by any means, but Redyue stands out for her willingness to use any means necessary to play mind games with, and to commit genocide against, humanity out of boredom. As a vile, selfish, and manipulative bitch, Redyue corrupts Mitsuzane Kureshima into becoming her puppet and uses him to obtain human subjects for a machine that would revive the dead. She aggravates the humans into launch missiles, thereby forcing her superior Roshuo to redirect the missiles to America and to declare war against humanity. She is also not above Mind Rape, as seen when she tries to mentally break Kouta Kazuraba by portraying him in a hallucination as an Inves being attacked by his former mentor Yuya. Moreover, Redyue has a sickening obsession over backstabbing and killing those close to her as seen when she ruthlessly kills Roshuo after the latter defeats Kouta and Kaito Kumon.

Kamen Rider Drive

Kamen Rider Amazons

Kamen Rider Ex-Aid
  • Masamune Dan/Kamen Rider Cronus is the first CEO of Genm Corp., and the father of Kuroto Dan. In his first appearances, he appears to be an innocent victim of circumstance, ashamed of his son's evil deeds. However, he reveals that in truth, he stood by and let Kuroto execute and frame him for Zero Day, where countless people were infected by and died to the Bugster Virus, to aid his plans for Kamen Rider Chronicle. Once in charge of the game, he uses it to motivate people into playing it until enough people have died, turned into data for his keeping, and he may do what he chooses with everyone's lives. When Hiiro opposes him to get Saki back, he uses her data to blackmail him to task him with betraying his friends, destroying Emu and Parado to prevent any opposition, and sabotaging Taiga's heart surgery so he would die; when Hiiro refuses to go through with it, he deletes Saki's data. In battle, it was common for him to play dirty by freezing time to stop anyone from moving, stealing all the Energy Items for himself, and reseting time itself to a point before his powers could be opposed. Upon the arrival of Gamedeus, Masamune reprograms him to spread an even deadlier Bugster Virus everywhere he walks in order to infect the entire world and turn them into data, destroying and absorbing Gamedeus when that fails. Combined with Gamedeus, Masamune turns into a One-Winged Angel that turns all infected by his virus into mindless Bugster Viruses that spread it to all they touch, and would also die if he did. After he's finally defeated and offered a chance to repent, he refuses and kills himself to make sure the Riders could never revive those killed. As pieces of his facade fall away, Masamune is revealed to be a sociopath with a god complex who was only concerned with other people's lives if he could control them.