[2][3][4][5] The club's headquarters is the remains of the Rabbit Hatch (ラビットハッチ, Rabitto Hatchi) lunar base, which is accessed by a Cosmic Energy (コズミックエナジー, Kozumikku Enajī) powered portal found in a locker in an abandoned section of the AGHS campus and was originally owned by the Outer Space Technology Organization (外宇宙技術開発機構, Gai Uchū Gijutsu Kaihatsu Kikō) abbreviated as OSTO (オスト, Osuto), which developed Fourze's technology and the Zodiarts Switches.
While transformed, he can activate the Astroswitches' Fourze Modules (フォーゼモジュール, Fōze Mojūru) to assist him in combat and perform Limit Break (リミットブレイク, Rimitto Bureiku) finishers based on his active Modules, with his primary Limit Break being the Rider Rocket Drill Kick (ライダーロケットドリルキック, Raidā Roketto Doriru Kikku) via the Rocket (ロケット, Roketto) and Drill (ドリル, Doriru) Switches.
After losing Rokuro the day he was born and a year before the series, Kengo discovered the Fourze System, Rabbit Hatch, and the Zodiarts' existence and took on his father's mission to fight the monsters.
Due to his weak physical constitution however, which he believed was a medical condition, Kengo is unable to properly utilize Rokuro's equipment and is forced to let Gentaro take his place while he serves as a tactician.
When her fellow cheerleader Tamae Sakuma humiliates her and reveals the negative aspects of her personality in front of their classmates in an attempt become the new queen however, a humbled Miu is reminded of her passion and returns to compete in the Festival despite the odds being against her.
After winning a third time, she accepts Gentaro's friendship and joins the Kamen Rider Club, using her natural leadership skills to become its president and working with Kengo to coordinate group efforts.
Kaizo Jingu (神宮 海蔵, Jingū Kaizō),[e] better known as "JK" (JK（ジェイク）, Jeiku, pronounced "Jake"), is a cowardly first-year, later second-year, AGHS student with a gaudy appearance who serves as an information broker, trading secrets for favors.
However, JK is captured by Nitta, rescued by Kisaragi, and learns the true meaning of friendship before joining the Kamen Rider Club, using his connections to aid the group in identifying Switchers, Zodiarts, and their targets.
When Goto returns as a Zodiarts and uses his powers to increase the show's popularity, JK finds himself conflicted by his loyalties to the Kamen Rider Club and refusal to give up on his dreams like his father had.
After a series of events lead to him receiving detention with Gentaro Kisaragi and the Kamen Rider Club, Shun reveals his history to them, how he is not truly happy with who he is or what he achieved, and that he considers himself an outcast due to his holier-than-thou attitude.
Despite being disappointed by the coldness of space, Tomoko finds comfort and acceptance in the Kamen Rider Club, joining them and providing assistance with her ability to detect things others overlook.
Ryusei Sakuta (朔田 流星, Sakuta Ryūsei) is a mysterious transfer student from Subaruboshi High School (昴星高校, Subaruboshi Kōkō),[h] and a former member of the Anti-Zodiarts Union (反ゾディアーツ同盟, Han Zodiātsu Dōmei) After his friend Jiro Iseki used a Zodiarts Switch that put him in a coma, Ryusei never forgave himself and vowed to never make friends again before receiving the means to become Kamen Rider Meteor (仮面ライダーメテオ, Kamen Raidā Meteo) and the task of locating the Aries Zodiarts from Tachibana.
Due to his search taking him to AGHS, Ryusei puts on a timid demeanor to infiltrate the Kamen Rider Club and secretly report on their activities for Tachibana while assuming his true aggressive nature as Meteor.
He also wields the Meteor Galaxy (メテオギャラクシー, Meteo Gyarakushī) brace, which grants abilities based on Mars, Jupiter, and Saturn as well as allow him to perform the Starlight Shower (スターライトシャワー, Sutāraito Shawā) Limit Break.
Gamou created the Zodiarts and Horoscopes to withstand the rigors of transwarp travel and generate negative Cosmic Energy to convert an atmospheric vortex above AGHS known as "The Hole" (ザ・ホール, Za Hōru) into an extra-dimensional labyrinth called the Dark Nebula (ダークネビュラ, Dāku Nebyura) so he can reach the Presenters.
As a child, Gamou heard the Presenters' call around the time of the Apollo 11 exploration, motivating him to join NASA, the Russian Federal Space Agency, and the OSTO in an attempt to meet them.
Before he dies, he asks the Kamen Rider Club to meet the Presenters in his stead before using the Aquarius Zodiarts' powers to repair the Core Switch and resurrect Kengo.
As the Sagittarius Zodiarts, Gamou possesses durable armor and can generate the Gilgamesh (ギルガメッシュ, Girugamesshu) bow on his left arm, which can fire a barrage of Cosmic Energy arrows.
After being defeated by Fourze and Meteor despite attaining her Supernova powers and maintaining her secret identity however, Kuniteru Emoto seemingly banishes Sonoda to the Dark Nebula for her failure while Gamou acquires her Horoscope Switch and covers up her disappearance as a sabbatical, later resignation, for health reasons.
The former's desperation over staying with Gamou causes Hayami to manifest his Supernova ability, the Eye of Laplace (ラプラスの瞳, Rapurasu no Hitomi), which allows him to directly identify people who can evolve into Horoscopes by viewing their "Fate of the Stars" (星の運命, Hoshi no Sadame).
In pursuit of this, Emoto became the Virgo Zodiarts (ヴァルゴ・ゾディアーツ, Varugo Zodiātsu) to seemingly serve as Gamou's judge and executioner within the Horoscopes' ranks while secretly sending potential victims to the M-BUS for their own protection, assume the identity of the masked "Tachibana" (タチバナ) to secretly gain Kamen Rider Meteor and Rokuro's son Kengo's help, and utilize his occupation as a Kyoto Space University (宇宙京都大学, Uchū Kyōto Daigaku) professor to study a version of The Hole above Kyoto; using his Zodiarts form's teleportation powers to maintain all of his plans and identities.
As the Virgo Zodiarts, Emoto wields the Rhodia (ロディア, Rodia) halberd, can produce formidable barriers, fire black hole-like orbs, and conjure portals to send targets to other locations.
Quickly winning Mitsuaki Gamou's favor, Kijima tactlessly flaunts his increased power, challenges Kamen Riders Fourze and Meteor constantly, and belittles Hayami for not treating him as an equal.
While studying Cosmic Energy with Mitsuaki Gamou and Kuniteru Emoto, Utahoshi reverse-engineered the Fourze System from the Core Switch in the hopes that the finalized versions would be made for future generations after his death.
As his Zodiarts form evolves however, Kusao becomes addicted to the Switch's power and his mental state grows increasingly unstable until Fourze restrains him long enough for Kuroki to apologize for being overprotective of him.
While searching for a mysterious substance called SOLU, which is only found in two meteorites that collided with Earth, he mutated human test subjects into the Super Evolved Lifeform Mutamits (超進化生命ミュータミット, Chō Shinka Seimei Myūtamitto) and created the Dummy Inhumanoids (ダミー怪人, Damī Kaijin), which are capable of assuming varying monstrous forms, from his mobile spaceship lab, Exodus (エクソダス, Ekusodasu).
He is equipped with the chest-mounted Grounblaster X (グランブラスターX, Guranburasutā Ekkusu) cannon, has the ability to use his Cosmic Energy to summon Dustards like the Horoscopes, and can transform into a car-like form called the Grouncar (グランカー, Gurankā).
She is equipped with the twin arm-mounted Skycutter (スカイカッター, Sukaikattā) blades and can transform into a jet-like form called the Skyjet (スカイジェット, Sukaijetto), which allows her to fire Skymissiles (スカイミサイル, Sukaimisairu).
In battle, Black Knight possesses armor that increases its defensive capabilities and wields the Blackest Reaper (ブラッケスト・リーパー, Burakkesuto Rīpā) rapier and a machine gun built into his chest.
Upon learning his mistake and receiving help from his teacher Gentaro Kisaragi, Kazeta finds the will to fight for justice and transforms into a blue moth-like mutant called Inazuman (イナズマン) to defeat Banba.