Ryoma Sengoku

, was the head of Yggdrasill Corporation R&D and the inventor of both the Sengoku Driver and Genesis Driver who transforms into . After his demise, he is temporarily revived by Megahex.
==History==
===Early Life===
Like Touka Akatsuki, he spent his childhood in the now-defunct Zawame Child Care Facility, where children with potential are experimented on and brutally raised to work for Yggdrasill in their future. Under Amagi Kureshima, he created his first products, the fully successful Forbidden Ringo Lockseed (although it has a negative side-effect), and a negative life draining prototype Yomotsuheguri Lockseed. Ryoma, in his horror, had witnessed the destruction of Kugai Kudo due to the negative impact of Forbidden Ringo Lockseed in its testing, which it went horribly wrong. He was eventually able to become a researcher for the company later in his life.
He met Takatora Kureshima at some point where they decided to work together to develop the Sengoku Drivers. He also the one who recruited Sid and Yoko to his side.
During a development of the Sengoku Driver with Takatora, the first test failed until in the present, the prototype version has been completed. Prior to Takatora getting medical attention, Ryoma got a report from Yoko of the Inves' leader called an Over Lord, which is the image that appears to be Demushu existing in the ruins, without telling Takatora about the Inves' leader's existence due to Takatora's insistence of putting humanity first above themselves.
He was also involved in recording the fate of Yuya Sumii in Helheim and Kouta Kazuraba's first transformation as Gaim is unaware he was fighting his own friend.
===Beat Riders Saga===
Sometime after the events of Bravo defeating Gridon and Kurokage, Ryoma arranges a meeting about Oren's portfolio, a man with military training. Later, Ryoma talks to Takatora about the new model which he replies to Ryoma that he will test the belt for humanity's sake. After, being requested by Sid to have multiple Lockvehicles, Ryoma views this as an opportunity to have all 7 prototype Sengoku Drivers in the Helheim forest. However, seeing Takatora is not pleased to have street rats in the forest, Ryoma warns Takatora to not destroy his precious work. During the Inves breakout of this event as they run rampant to Zawame City, Ryoma aids Gaim through the use of the Yggdrasill's tower through the use of a cloaking mechanism and beam weaponry.
Sometime during this saga, Ryoma created the experimental Lockseed, the Yomotsuheguri Lockseed to see if he could tap more power from Helheim given the Sengoku Driver's limitations. The prototype was abandoned due to the fact that the Yomotsuheguri Lockseed drained the lifeforce of its user at the cost of power (which unknown to everyone, it rivaled the power of the Kiwami Lockseed, a seed of the Golden Fruit). Ryoma also noted that the first Lockseed he created was dubbed the Ringo Lockseed which gives a potent amount of power that allows users to manipulate Cracks at will. However, the Ringo Lockseed overwhelmed its user by spouting Helheim vines from the Ride Wear. Ryoma also worked on a successor prototype of the Suika Lockseed dubbed the "Watermelon Lockseed" because the Suika Lockseeds were hard to come by and had to recharge. This Lockseed was scrapped due to the fact that the output of the Watermelon Lockseed was inferior to the newly created Energy Lockseeds and that the Watermelon Lockseed drains the stamina of the user much more quickly.
Also sometime during this saga, Ryoma is aware about the existence of Kugai Kudo and the Black Bodhi. He finally meets Kudo before the hypnotized blank Zakuro Lockseed users are about to kill him by explosion before Takatora quickly arrives to save Ryoma. Ryoma later discovers the hidden location of Kudo's artificial Lockseed warehouse. As Ryoma and Takatora enter into the warehouse, they meet Kudo, who transforms into Armored Rider Saver. Takatora and Ryoma transform into Armored Riders by using their Sengoku drivers to fight Saver, until Takatora overpowers Kudo.
===Yggdrasill Saga===
Few days later, Ryoma finally completes four Genesis Drivers along with four Energy Lockseeds. Ryoma goes back to Kudo's warehouse to confront him once again. Ryoma resolves that though Takatora will be his obstacle, he still acknowledges him and mocks Kudo that is just a third-rate cannot be considered a potential person to acquire Godhood before Ryoma transforms using his Genesis Driver to fight Kudo as Saver. Ryoma finally defeats Kudo by shooting his Sengoku Driver directly.
Ryoma later has Takatora test the Genesis Driver, impressed with its output and stating that they're one step closer to understanding the Helheim forest. Ryoma is seen once more, transforming with the Lemon Energy Lockseed, and watches Sigurd kill Ryoji Hase. In the aftermath of this event, he formally introduces himself to Kouta and Kaito, asking for their permission to continue using them in his quest for power. However, when the two escape, he finds himself puzzled when his equipment (the Lemon Energy Lockseed and the Genesis Core slot) is stolen. Though, initially confused on why someone would steal the incomplete core slot prototype, Ryoma uses the data fed back from Kouta's Sengoku Driver to improve the mass-production models. Realizing Mitsuzane's inner darkness, he covers his actions when he "betrays" Yggdrasill by aiding Kouta. When he views the readings of the data fed back from the fight between Jimber Lemon Gaim and Marika, Ryoma decides to test out his Genesis Driver on Kouta. While apologizing for his inability to restrain his power, he easily decimates Jimber Lemon Gaim and Baron without breaking a sweat. After canceling his transformation, he realizes that Yoko never used the Genesis Driver to it's maximum potential, wondering why she's holding back. After hearing about Kaito's speech about strength and power, he manipulates Kaito into searching for the Over Lords without giving him the necessary preparations to combat them, although Kaito was already aware what Ryoma's up to. During Kaito's search for Demushu, Ryoma apologizes about Kaito's family's downfall caused by Yggdrasill when they bought and destroyed Kaito's father's construction factory in the past, remarking that Yggdrasill knew Kaito's father's weaknesses, such as greed for money, which also leads him to become corrupted and alcoholic towards his family, thus both Kaito's parents ended up committing suicide, and leaving Kaito an orphan and losing the ability to trust someone whom he sees as weak.
When Yggdrasill is under attack by an unknown Armored Rider who can produce Helheim power one by one, Ryoma was informed by Takatora from Yoko, who managed to survive the attack and identify what the Armored Rider looked like and who attacks Yggdrasill members one by one, such as the Kurokage Troopers and even Sid. Ryoma gave a prototype version of Suika Lockseed, Watermelon Lockseed to Takatora, just in case Takatora loses his Genesis Driver equipment and needs to use his Sengoku Driver as a back up plan. Upon learning the Armored Rider has the ability to create Cracks at will, Ryoma became concerned and realized what Lockseed the Armored Rider used, although only Takatora thought Ryoma might have been thinking about something to do with the orphanage under the direction of Takatora's father, Amagi, in which Ryoma used to belong to, despite Takatora being unaware of Ryoma's origin.
After Takatora discovered that the identity of the Armored Rider who attacked Yggdrasill was actually Touka, he spared her and left her to atone, due to never treating her as a slave in the past. Ryoma revealed himself to Touka about his origin, along with a life draining prototype Yomotsuheguri Lockseed he created in the past, then kills her to take the Ringo Lockseed back, while Touka is weakened due to the Lockseed, without Takatora knowing.
Sometime during this time after taking the Ringo Lockseed from Touka, Ryoma Sengoku worked on the prototype of the Dragon Fruits Energy Lockseed and gave it to Alfred. Though the Lockseed was destroyed and consumed Alfred, creating a pseudo Over Lord, Ryoma sent Yoko to give Kaito the Ringo Lockseed to test the strength of the Ringo Lockseed and to destroy Alfred. Though Kaito destroys Alfred, the latter also destroys the Ringo Lockseed as well.
When a Crack appears on a bridge in the middle of the city, he asks Takatora if they should resort to use the Scalar System, however Takatora wants to minimize damage as possible, sending Ryoma down to the other side of the Crack in the Helheim Forest. With a squad of Kurokage Troopers, Marika, and Gaim, he explains to Kouta about Project Ark and how humanity will be culled down to one-seventh in order to kill off the potential 6 billion Inves that might come into fruition in the next ten years. In addition to this revelation, he also tells Kouta that the Sengoku Driver will help the remainder of humanity as it converts Helheim's fruits into Lockseeds and enables the wearer to absorb the nutrients safely without side effects. As the Crack closes, Kouta steals Yoko's Peach Energy Lockseed and rushes to HQ to destroy the Scalar System.
===Helheim and Over Lord Saga===
Ryoma apologizes to Mitsuzane for revealing classified information to Kouta. Though Kouta ignores Mitsuzane's pleas to stop, Ryoma is shocked and angered when Kouta utilizes the Kachidoki Lockseed, a Lockseed not created by him. Realizing that someone is helping him from the shadows, he tasks Mitsuzane to investigate Kouta to find out who is helping him. Takatora, along with the group are informed of creatures that were more than a threat to humanity than the Inves by Mitsuzane. Realizing that their chance for power is dwindling, Ryoma gives Sid another Cherry Energy Lockseed, hoping that Sid will kill Kouta this time.
When Sagara appears in Ryoma's office. Ryoma reveals that mythology of a greater power is really the forbidden fruit of the Helheim and that Helheim has been here since the beginning of civilization. However, before he can have a longer conversation with Sagara, Sagara disappears telling them to find the Over Lords.
After analyzing the battle of the Over Lords with Baron, Ryoma kicks Kaito off the team as he can no longer fight the Over Lords with just his Sengoku Driver. However, Yoko requests for another chance for Kaito, giving him a Genesis Driver replacement. When figuring out how to find the Over Lords, Mitsuzane tells them that they can easily find the Over Lords if they adhere to his plans.
Reminiscing about the Sengoku Driver's origin, he is reminded of the day when he starts a separate path rather than work together with Takatora. When Takatora enters the room, Ryoma explains to him that there is no possible way to get more than a billion Sengoku Drivers. As the alarm sounds off, the Over Lords make their first appearance to Yggdrasill, going on the offensive, destroying the campsite. Upon Takatora's realization of the Over Lords, Ryoma decides to dispose of Takatora while he still has the chance. Transforming into Genesis Armored Rider Duke, Ryoma defeats Takatora and has Sid slash him down and throw him off a cliff. While in the headquarters and erasing all records of Takatora Kureshima, he finds Sid destroying the equipment around the tree, causing the Headquarter's Crack to disappear and close.
Later, he informs Kouta, Kaito, and Mitsuzane about Sid's betrayal as he offers them a task to stop him from getting the Forbidden Fruit. With the Over Lord's attack in Zawame City, Duke activates the Master Intelligence System, cutting off all communication devices in the city except for his own platoon that are engaging Demushu. When Demushu escaped after being overpowered by Baron and Knuckle, the Helheim's plants started to invade Yggdrasill Tower. Duke abandoned Marika and Yggdrasill as he leaves by a Rocket, leaving the rest to her.
===Forbidden Fruit Saga===
Ryoma later shows up in a holographic conference with Yggdrasill's executives of their international branches from London, Hong Kong and Paris. When the Executives threaten to arrest him after an investigation of what the Japan branch did to cause this disaster, Ryoma activates a bug in the executives' phones which sends information to the world about Project Ark's culling of the population, causing everyone worldwide to panic.
Returning to Zawame, he witnessed the battle between the Kureshima brothers, until Kouta shows up only to find Takatora's destroyed Sengoku Driver and Melon Lockseed. He later follows Kouta to Team Gaim's garage and mocks him about what happened to Takatora. Angering Kouta, Ryoma battles him until he is ambushed by Knuckle and Baron, as he cancels his transformation and is taken under the alliance's custody. Ryoma then reveals to the group that they can enter the tower by a secret pathway that he had used to escape Zawame City, before leaving the garage.
After leaving Zawame, Ryoma and Kouta are the only members able to infiltrate into Yggdrasill Tower while Oren alongside Hideyasu fought an army of Inves, Kaito alongside Yoko and Zack distracting Ryoma's turned off Suika Arms soldiers and Tulip Hoppers security. They are halted by Shinmugurun and Kouta fights it. Ryoma soon helps Kouta with the reasoning that it will be too bad for losing a needed test subject and also to show Kouta how to use the Genesis power in the right way. He proved himself to be even more superior than Kouta by defeating Shinmugurun very easily without a scratch. But, he decided to not finish him off and see how Kouta will continue it. He takes the data of Gaim Kiwami Arms when Kouta accesses it. After the battle was over, he makes a thought that it will be interesting to collect more data about Kouta's new power.
Once they reach the site where the kidnapped citizens are, Redyue appears to fight them, however Duke retreats while Gaim continues to fight the Over Lord. Later, Duke manages to reboot the Master Intelligence System, seeing that the Inves didn't invade his property as he checks the records prior to the Inves invasion. Once he heard Rosyuo's name while analyzing the footage, he thinks that the Over Lord currently has the Forbidden Fruit in his possession.
Once he found where Mai is, the possession of the Forbidden Fruit, and the Over Lords' leader to the remaining Armored Riders as Kouta and Kaito left, Ryoma also follows Kouta and Kaito in cloaking mode, in order to gather data of Rosyuo's power in Helheim. When the Forbidden Fruit from Rosyuo expires into nothingness and Mai went back to Earth, Ryoma also heard there's another Forbidden Fruit that Rosyuo's hidden and discovered that Rosyuo had planted the Forbidden Fruit in Mai. Ryoma returns to Zawame to take Mai to the hospital, along with Peko, Chucky, and Mitsuzane. Once they reach to the hospital, he examines her body as Ryoma believes that she might lose her humanity to become an Over Lord as this would shock Mitsuzane a lot. They then wonder about Rosyuo's purpose of handing the Forbidden Fruit to Mai as Sagara appears to them that she will become the first woman and reveals his true identity to them as Helheim himself. After Sagara explains his purpose to them and disappears, Ryoma informs Mitsuzane that he can remove the fruit from Mai, but believes that Kouta would interfere. Ryoma would give Mitsuzane the Yomotsuheguri Lockseed and warns him the consequences of using it before he leaves. What Ryoma doesn't tell Mitsuzane is that to remove the Golden Fruit from Mai he intends to kill and dissect her, which he does before disabling Mitsuzane's Genesis Driver and promptly strangling him. However, the Golden Fruit manifests into an apparition of Mai and leaves the area.
Ryoma is then encountered by Kaito and Yoko and he disables their Genesis Drivers when they attempted to transform to avenge Mai. Despite Kaito trying his best as Baron Banana Arms, Duke still defeated him easily. After being mocked by Ryoma, Kaito gambled his own life by eating a Helheim Fruit. However, he instead changed into an Over Lord Inves, Lord Baron. Disgusted by Kaito's action, Ryoma tried to fight Lord Baron but was easily defeated and beaten. Ryoma then falls to his death over the edge of a building, but not before telling Kaito that he won't survive long.
==Other Events==
===The Fateful Sengoku Movie Battle===
At the end of the movie, Takatora watches Kouta, Kaito, Mitsuzane and Mai leaving the forest back to the real world as Ryoma and Yoko shows up to him and Ryoma gives him the Genesis Driver, as well as showing their Lockseeds. 
===Gaim Gaiden: Kamen Rider Zangetsu===
Ryoma meets Takatora in his office and presents him the Watermelon Lockseed to compensate for the one he originally lost. With given information that the attacker is not a Beat Rider, but an affiliate of Yggdrasill.
Touka using the Lockseed indirectly helped Ryoma in his study to confirm the existence of Forbidden Fruit. Now no longer finding her useful, Ryoma transforms into Duke and kills her in cold blood.
===Gaim Gaiden: Kamen Rider Baron===
Ryoma meets Alfred also his Foundation wants to help Ryoma monetarily, on the other hand, Ryoma wants this monetary aid to be for him and not for Yggdrasill, Alfred wants to purchase 500 Sengoku Drivers , Ryoma listening to this Alfred words he convinced that is unnecessary many Sengoku Drivers and he gives to Alfred an upgrade Genesis Driver, he plans to give him the rest after receiving the funds for his development, but secretly Ryoma planned this from the beginning to use Alfred as a guinea pig for this experiment when Alfred uses the Genesis Driver.
Later, Ryoma orders Yoko to give the Ringo Lockseed to Kaito, so that he ends quickly in his fight against Tyrant
===Gaim Gaiden: Kamen Rider Duke===
Ryoma Sengoku continues his research of the Sengoku Drivers along with Takatora Kureshima. Takatora thinks that the lives of humanity was the number one priority, however Ryoma disliked his way of thinking increasing the production with cost as the main priority than efficiency.
Meanwhile Sid and Yoko investigate a suicide attack that was taking place in Yggdrasill. The mastermind of this incident was the Black Bodhi. They come to know that one of Ryoma's former colleague was part of Black Bodhi and had used the Zakuro Lockseed to brainwash people. Ryoma knows this is impossible, because his former colleague died in the Out-of-Control Lockseed incident a long time ago.
Kugai intentionally making his actions aware to Yggdrasill, he taunts Ryoma Sengoku, proclaiming that he can guide him to the path of God alongside him, testing him to overcome his labors. Due to Sid's interference to stop brainwashed members of Black Bodhi and acquiring one of the blank Lockseeds, Ryoma and Takatora track his location, discovering his artificial Helheim factory.
Kugai demonstrates to Ryoma that he is the final task he must overcome, utilizing a Genesis Core Unit as an extension of his Sengoku Driver with his Zakuro Lockseed modified to summon a variant of the Sonic Arrow called the Saver Arrow. Initially gaining the upperhand, fighting Duke and Zangetsu as he can overpower them one on one, he is defeated by their combined efforts.
Days later, Ryoma finishes his Genesis Driver with the intent to destroy Kugai for good. Ryoma taunts Kugai saying that he is third rate and cannot be considered a potential person to acquire Godhood. During his second encounter, Ryoma damages his Sengoku Driver, causing Kugai to wallow in pain as the Driver is what maintains his physical form. Kugai dies when Ryoma shoots his Sengoku Driver directly.
===Kamen Rider Gaim: Final Stage===
Ryoma was revived by Maja among other deceased Armored Riders and Inves as servants, However, when Gaim Kiwami Arms appeared and attempts to stop him, the revived Armored Riders under Maja's control easily defeated Gaim and absorbed his powers into 4 stones, turning him into Orange Arms lost memories. He, like the other Riders servants, enter the world of the living.
In Zawame city, Duke and the other revived Armored Riders confront Bravo, Gridon, Knuckle, and Gaim when Maja turned into Kamen Rider Gaim Yami, Duke and Sigurd easily defeated Bravo and Gaim, in the moment when Maja made a final fist to Kouta until Takatora as Zangetsu Shin and Mituzane as Ryugen appear surprisingly and his enemies escape.
Later Duke is seen among the revived Armored Riders, demonstrated his complete servitude to Maja,
Ryoma and Sigurd cornered and dominated Ryugen in the battle. They used Sonic Volley against Ryugen, seriously injuring him before giving the final attack to Ryugen, however Zangetsu Shin appears surprisingly before them, Duke and Sigurd are killed by Kureshima brothers finishers, in Duke's case, he is killed by Ryugen Dragon Shot and Sigurd was killed by Zangetsu Shin's Sonic Volley.
In the moment when Maja turned into Kamen Rider Maja and Kouta recovers his memories and received Kiwami Arms, all of the Armored Riders gather together and do a roll call with all Riders battling against the recent revived Over Lords. Duke and Sigurd made a team-up by the last time against Grinsha and easily dominated in the battle and finally used a Rider Slash and Sigurd uses Sonic Volley to kill Grinsha. Later Duke and Sigurd disappeared. 
===Movie War Full Throttle===
In the film Movie War Full Throttle, the mechanical lifeform Megahex uses Kouta's memories of the original Ryoma to create the cybernetic to prevent any from meddling in his affairs. As he is a convincing facsimile, seeing himself as Ryoma reborn, Mecha Ryoma considers himself as the realization of the original's desire of becoming a godly being. Using the Dragon Energy Lockseed, Mecha Ryoma drives off Mitsuzane Kureshima before he and Takatora face him the following day. As Mitsuzane leaves to save Mai, Takatora becomes Zangetsu and settles his affairs with Ryoma in a decisive battle that ends with Kamen Rider Zangetsu fatally wound Mecha Ryoma with the robot lasting long enough to speak some last words to his former friend. Mecha Ryoma's Genesis Driver would be later taken by Takatora to transform into Kamen Rider Zangetsu Shin once more.
===TV===
====Super Hero Time====
Kamen Rider Duke alongside various other New Generation/Armored Riders poses with the in the Gaim/ Super Hero Time opening. He also clashes with at one point.
==Video Game Appearances==
===Kamen Rider Battle: Ganbarizing===
Duke is among the vast majority of Kamen Riders that are available in this arcade game. Notably, he is shown to use the Legend Rider Lockseed to assume Wizard Arms in Kamen Rider Battle: Ganbarizing.
duke videogame.JPG
g4378230.jpg|Kamen Rider Duke card
88b55c767518a797f9dcaf93a82a1117.jpg|Kamen Rider Duke Wizard Arms
===Kamen Rider Batton-Line===
Kamen Rider Duke appears as a playable character in Kamen Rider Batton-Line among other 
Riders in the game.
===Kamen Rider Riderbout===
Kamen Rider Duke appears as a playable character with the other Heisei and Showa Kamen Riders in Kamen Rider Riderbout.
===Kamen Rider Battle Rush===
Kamen Rider Duke appears as a playable and support character in the video game Kamen Rider Battle Rush using Sonic Volley.
Chibiduke.PNG|Duke in Kamen Rider Battle Rush
duke'ssocinvollay.PNG|Kamen Rider Duke using Sonic Volley
===Kamen Rider Buttobasoul===
Kamen Rider Duke is a playable character in Kamen Rider Buttobasoul among other Riders in Kamen Rider Buttobasoul.
Duke Lemon Energy Arms Medal.jpg|Kamen Rider Duke Lemon Energy Arms medal
Duke Lemon Arms Medal.jpg|Kamen Rider Duke Lemon Arms medal
===Battle Spirits===
Kamen Rider Duke Lemon Energy Arms is a playable character in Battle Spirits with other Kamen Riders.
==Personality==
Ryoma was one of Takatora's subordinates, and his and Sid's closest friend, a brilliant scientist in the Yggdrasill Corporation's research division who conducts experiments on the Lockseeds and is the inventor of the Sengoku Drivers and the Genesis Driver.
He is amoral in terms of using people as test subjects and expresses no interest in the Inves-based infections as his company's plan is his main focus. Despite his status as a scientist, he is dangerous in a fight, proven when he easily defeated Kouta in Jimber Lemon Arms (who managed to put up a good fight against the other Genesis Armored Riders at the time) and Kaito in seconds with his sheer power. However, he rarely transforms and fights by himself. As shown, he would let the Kurokage Troopers and Marika fight the Inves in the Helheim forest and let the aforementioned riders capture Demushu while he himself just watched from a saferoom and eventually runs off leaving Marika and the Kurokage Troopers to die.
It is shown that he cares about his inventions, and want people to show respect and trust on them. When Kouta revealed his newly-gained Kachidoki Arms, Ryoma showed a bit of anger and jealousy that such a Lockseed was not his creation, displaying him as arrogant. Yet as a scientist, Kachidoki Arms is an unknown factor, with the above showing disdain for not knowing how Kouta got the Kachidoki Lockseed and immediately picks up the fact someone is helping Kouta, but doesn't know who. This is also shown when Kaito became Lord Baron, making Ryoma really angry because someone could survive the Helheim Fruits' side effects without his inventions. An ironic element of his jealousy is shown by how he failed to see that his inventions played a part in Kachidoki Arms' evolution to Kiwami Arms, and that Kaito's transformation was catalyzed by the Genesis Driver allowing the infection Kaito received to develop into an immunity to Helheim's fruits. In Gaim Gaiden: Baron, when Alfred wanted to receive funding including 500 Sengoku Drivers, once again, he is a bit angry of Alfred's actions due to his thoughts of his research being mocked, so he decided to trick him into being his test subject for the Lockseed.
Ryoma can be manipulative at most of the times, such as when he manipulated Takatora and later Mitsuzane. Because of this, he prefers to act behind the stage and let the others fall to his manipulation for his own benefit. He is also unconfident about his own power, which is shown when he abandoned Yggdrasill and abused Duke's power, despite Duke already being the strongest Rider in general. Because of this, he tends to battle enemies with his abused power. He also created the Genesis Driver's kill switch in order to make sure that he won't be matched in power.
== Abilities ==
* Genius-Level Intellect: To be added
* Master Engineer: To be added
* Master Scientist: To be added
==Forms==
Like the Armored Riders and his fellow Genesis Armored Riders, Kamen Rider Duke's forms are called . His Genesis Driver announces before every transformation.
By pushing the Genesis Driver's Seaboll Compressor into the Energy Lockseed after transforming from one to two times, Duke can activate one of two finishing moves based on his current Arms form: or . In addition to the Genesis Driver's finishing moves, Duke can perform a finishing attack by inserting an Energy Lockseed into the Energy Drive Bay of his Sonic Arrow.
==Equipment==
===Devices===
*Genesis Driver - Transformation device (taken by Yoko Minato to transform into Marika after Ryoma's death, replacing her own which he had disabled).
*Sengoku Driver - Initial transformation device.
*Lockseeds - Gives access to Duke's Arms changes, depending on which lock is used.
===Weapons===
*Arms Weapons
**Sonic Arrow - Duke's personal weapon in Lemon Energy Arms.
**Lemon Rapier - Duke Lemon Arms' personal weapon.
**WizarSwordGun - Duke Wizard Arms' personal weapon.
*Hakaider Shot - Hakaider's personal weapon.
==Behind the Scenes==
===Portrayal===
Ryoma Sengoku is portrayed by , who previously portrayed in . His character in that show also used a bow and arrow as weapons similar to his current character's Kamen Rider alter ego.
As Kamen Rider Duke, his suit actor is who was previously the suit actor for Kamen Rider Kuuga, Kamen Rider Bujin Gaim and Kamen Rider Fifteen. As Hakaider, his suit actor is who is also the suit actor for Kamen Rider Baron and Lord Baron.
===Concept Art===
Duke Lemon Energy Arms concept art.png|Kamen Rider Duke Lemon Energy Arms concept art
Lemos Headpiece & Steering Eye concept art.png|Kamen Rider Duke Lemon Energy Arms concept artLemos Headpiece & Steering Eye
Duke Lemon Arms concept art.png|Kamen Rider Duke Lemon Arms concept art
==Notes==
*He is the only Genesis Armored Rider in the series whose Genesis Driver has a transformation announcement that says more than just "Soda! (Fruit) Energy Arms!" similar to the Armored Riders' Sengoku Drivers.
**This is most likely related to his claim that the extra part of the announcement in the Sengoku Drivers were a "guilty pleasure" of his.
***This "guilty pleasure" is further alluded to in the transformation announcement for Duke Lemon Arms, which praises Ryoma himself.
**The movie-exclusive Kurokage Shin's Matsubokkuri Energy Arms also has a transformation phrase.
*Contrary to his Machiavellistic nature, Ryoma seemed genuinely concerned for Takatora's well-being after he was hospitalized following the initial testing of the Lockseeds and Sengoku Drivers. It is unknown if this was an act or he genuinely held Takatora in high respect at one point.
*Foreshadowing to Ryoma's anger towards people who evolve without his assistance can be seen with Kouta's forms. When Kouta used the Jimber forms, accessed using his Energy Lockseeds, he didn't seem to mind and the closest thing he ever got to some form of concern is just wondering who managed to give him the Genesis Core, but other than that expressed intrigue. When Kouta used Kachidoki for the first time, he got notably upset over it. This was demonstrated again during his battle against Kaito following his transformation into Over Lord Baron, where he expressed disgust at the idea of a new world being made with no attribution to his inventions.
**This might also put a new interpretation to his reaction to Hakaider after he put his brain back in his body, seeing as he was horrified by its sheer power. It could be that he was horrified at the fact that someone managed to create something that he had no part of and that was potentially more powerful than what he could create.
*He is the only Genesis Armored Rider to use two different Energy Lockseeds.
**He would, however, be the first to use the complete version, and therefore the first to use it for his Final Form.
*He is one of two Armored turned Genesis Armored Riders to have the same Ride Wear when transforming with two different belts. The other to have this distinction would be Kaito Kumon.
**Oddly enough, his helmet still possessed the drinking straw-like details even when he was using a Sengoku Driver. The straw-like details were unique features found on the helmets of the main four Genesis Armored Riders. Production-wise, this was likely to save money on crafting a new helmet, though in-story, it may suggest that Ryoma had designed his own Sengoku Driver suit to match the Genesis Driver's form he was planning even before the new Drivers were finished.
*Chronologically, he's the first Armored turned Genesis Armored Rider to use an upgraded version of their primary normal Lockseed afterwards. Takatora was the first before Ryoma by production.
*Ryoma, along with Yoko Minato, holds the record of appearing in the most Kamen Rider Gaim Gaiden installments, having appeared in Gaim Gaiden Zangetsu, Gaim Gaiden Baron, and Gaim Gaiden Duke.
*Ryoma is the fourth (chronologically, the first) Rider to change drivers. The first being Takatora, second being Kaito, and third being Mitsuzane.
**Unlike Takatora who changed his Rider name from Zangetsu to Zangetsu Shin after acquiring the Genesis Driver, Ryoma was not called Duke Shin, even though he upgraded the Lemon Lockseed into the Lemon Energy Lockseed, chronologically speaking. Like Kaito, Ryoma's Ride Wear remains the same with both drivers. Thus, his Rider name remained the same even after changing from the Sengoku Driver to the Genesis Driver.
*Like Takeshi Asakura/Kamen Rider Ouja from Kamen Rider Ryuki, Ryoma is the second Rider who has died the most deaths among in the Kamen Riders series.
**In the movie, His Alternative Version was killed infected by Kohgane's grasshopper that causes his death in Kamen Rider Gaim: Great Soccer Battle! Golden Fruits Cup!.
**He was mortally wounded by Lord Baron and falls to his death over the edge of a Yggdrasill Corporation building in the TV series in Baron's Ultimate Transformation!.
**An Mecha copy created by Megahex is killed by the Melon Musou Zan of Zangetsu in Kamen Rider × Kamen Rider Drive & Gaim: Movie War Full Throttle.
**In the final stage, He is revived by Maja for later killed by Ryugen's Dragon Shot finisher in Kamen Rider Gaim: Final Stage.
**As Dark Rider killed by Brain's Brain Megane Blade in Drive Saga: Kamen Rider Brain.
===Legend Rider Lockseeds===
*The following Legend Rider Lockseeds are styled for Duke, as well as Baron, Gridon, and Idunn:
**Black RX - "Son of the Sun!"
**Shadow Moon - "King of Century!"
**Blade - "Sword of Spa~de!"
**Kiva - "King of the Vamp~ire!"
**OOO - "Tatoba, Ta~To~Ba!"
***OOO Tajadol Combo - "Ta~Ja, Ta~Ja~Dol!"
***OOO Putotyra Combo - "Pu-To-Tyranno~Sau~rus!"
**Ankh - "Happy Birth~day!"
**Baron - "Knight of Ba~nana!"
==Appearances==
==See also==
* - Original Hakaider.
==References==
Hakaider's stats on Kikaider REBOOT Official Website
==External links==
*Ryoma Sengoku on Kamen Rider Official
*Kamen Rider Duke Lemon Arms on Kamen Rider Official
*Kamen Rider Duke Lemon Energy Arms on Kamen Rider Official
*Hakaider on Kamen Rider Official
==Navigation==
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Category:Gaim Characters
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