List of Kamen Rider Zi-O characters

Sougo Tokiwa

Sougo Tokiwa (常磐 ソウゴ, Tokiwa Sōgo) is a kind-hearted and pacifistic 18-year old student at Hikarigamori High School (光ヶ森高等学校, Hikarigamori Kōtō Gakkō) born in the year 2000 who dreams of becoming a king in the future, a desire he can only explain as him somehow feeling that it was his fate. Upon meeting Tsukuyomi, Sougo is informed that he will become the King of Time; a Demon King destined to rule the world. Although troubled by the possibility that his cursed fate is to become a tyrant, Sougo chose to continue following his dream while changing his fate, accepting the power to become Kamen Rider Zi-O (仮面ライダージオウ, Kamen Raidā Jiō) and declaring that he would become a benevolent Demon King instead of a tyrant. Despite his personality, he can be quite cunning, as he was able to outwit and escape Geiz during the latter's second attempt on his life without even trying to fight back, and even gets the last laugh when Geiz tries to intimidate him after he and Tsukuyomi becomes house-guests at the Kujigojidō. Despite both Geiz and Tsukuyomi being wary of him, Sougo considers them friends and entrusts his life to them, asking for both of them to kill him should he follow the path of becoming Oma Zi-O.

It is shown that Sougo's time travelling and meeting Riders of the era he arrives in counters the paradoxes created by the Time Jackers when they turn humans into Another Riders because Sougo's identifying of the former Riders in the present day will trigger the return of their memories as well as the creation of the Ridewatches, as the Riders will remember fighting alongside him and Geiz in the past. However, as the Time Jackers' actions have permanently damaged the past, the Riders will have forget their identities up until they encounter Sougo in the present day. It is also revealed by Geiz that even with their memories restored in the present, the particular Kamen Rider remains missing from history.

To transform, Sougo uses the Ziku-Driver (ジクウドライバー, Jikū Doraibā, Space-Time Driver) in conjunction with the Ridewatches (ライドウォッチ, Raidowotchi). When transforming into his base form, the word "Rider" (ライダー, Raidā) appears written on Zi-O's visor with magenta-colored characters in katakana while Armor (アーマー, Āmā) forms based on a different past Rider have the respective Rider's name written in the same fashion. His personal weapon is the Zikan Girade (ジカンギレード, Jikan Girēdo), which has a Ken Mode (ケンモード, Ken Mōdo, Sword Mode) for the Giri Giri Slash (ギリギリスラッシュ, Giri Giri Surasshu) finishing move and a Ju Mode (ジュウモード, Jū Mōdo, Gun Mode) for the Zure Zure Shooting (ズレズレシューティング, Zure Zure Shūtingu) finishing move. He also owns the Time Mazine, a time traveling vehicle given to him by Tsukuyomi that can transform into a humanoid robot.

• Zi-O (ジオウ, Jiō): Sougo's personal Ridewatch, dated 2018, which allows him to transform into Kamen Rider Zi-O and convert his Time Mazine from Vehicle Mode to Robot Mode. His finishing move is the Time Break (タイムブレーク, Taimu Burēku).
• Bike (バイク, Baiku): An undated Ridewatch that allows Sougo to summon his personal motorcycle, the Ride Striker (ライドストライカー, Raido Sutoraikā).
• Build (ビルド, Birudo): Dated 2017, this Ridewatch is based on Kamen Rider Build (RabbitTank Form). It equips Zi-O with the Build Armor (ビルドアーマー, Birudo Āmā), granting him a weapon modeled after Build's Drill Crusher known as the Drill Crusher Crusher (ドリルクラッシャークラッシャー, Doriru Kurasshā Kurasshā). He can also increase either his agility or endurance via the Fullbottle Shoulders (フルボトルショルダー, Furubotoru Shorudā). This form's finishing move is the Vortex Time Break (ボルテックタイムブレーク, Borutekku Taimu Burēku). First used in Kamen Rider Build the Movie: Be the One.
• Ex-Aid (エグゼイド, Eguzeido): Dated 2016, this Ridewatch is based on Kamen Rider Ex-Aid (Action Gamer Level 2). It equips Zi-O with the Ex-Aid Armor (エグゼイドアーマー, Eguzeido Āmā), granting him a pair of weapons modeled after Ex-Aid's Gashacon Breaker known as the Gashacon Breaker Breakers (ガシャコンブレイカーブレイカー, Gashakon Bureikā Bureikā). He can also generate a Game Area with chocolate block-like platforms via the Gashat Shoulders (ガシャットショルダー, Gashatto Shorudā). This form's finishing move is the Critical Time Break (クリティカルタイムブレーク, Kuritikaru Taimu Burēku).
• Fourze (フォーゼ, Fōze): Dated 2011, this Ridewatch is based on Kamen Rider Fourze (Base States). It equips Zi-O with the Fourze Armor (フォーゼアーマー, Fōze Āmā), granting him a pair of weapons modeled after Fourze's Rocket Module known as the Booster Modules (ブースターモジュール, Būsutā Mojūru). He can also change into a Rocket Mode (ロケットモード, Roketto Mōdo) to gain flight capabilities. This form's finishing move is the Limit Time Break (リミットタイムブレーク, Rimitto Taimu Burēku).

Sougo Tokiwa is portrayed by So Okuno (奥野 壮, Okuno Sō).

Junichirō Tokiwa

Junichirō Tokiwa (常磐 順一郎, Tokiwa Jun'ichirō) is the owner of Kujigojidō and Sougo's granduncle. He usually helps Sougo with his knowledge.

Junichirō Tokiwa is portrayed by Katsuhisa Namase (生瀬 勝久, Namase Katsuhisa).

Geiz Myōkōin

Geiz Myōkōin (明光院 ゲイツ, Myōkōin Geitsu) is an 18-year old warrior from the year 2068 who fought as a resistance fighter against the tyranny of Oma Zi-O. He becomes Kamen Rider Geiz (仮面ライダーゲイツ, Kamen Raidā Geitsu) and travels back in time to kill Sougo before he can become the Demon King, unaware of the possible consequences from such an alteration to the timeline. Though certain to have a just cause against Sougo, he relents after Zi-O saves him and helps defeat Another Build, agreeing to Tsukuyomi's request that he stay his hand and watch the events play out, though he still refers to Sougo as Oma Zi-O instead of his actual name. He and Tsukuyomi become house-guests at the Tokiwa household to keep an eye on Sougo. He eventually comes to trust Sougo while maintaining his aloof attitude towards him, and is slightly disturbed when the latter entrusts him to end his life should he end up becoming Oma Zi-O.

Like Sougo, Geiz uses a Ziku-Driver with the Ridewatches in order to transform. When transforming into his base form, the word "Rider" (らいだー, Raidā) appears written on Geiz's visor with yellow-colored characters in hiragana while Armor forms based on a different past Rider have the respective Rider's name written in the same fashion. His personal weapon is the Zikan Zax (ジカンザックス, Jikan Zakkusu), which has a Yumi Mode (ゆみモード, Yumi Mōdo, Bow Mode) for the Kiwa Kiwa Shoot (キワキワシュート, Kiwa Kiwa Shūto) finishing move and an Ono Mode (おのモード, Ono Mōdo, Axe Mode) Mode for the Zakkuri Cutting (ザックリカッティング, Zakkuri Kattingu) finishing move. He also possesses his own red-colored Time Mazine, as well as a device modeled after Kamen Rider Faiz's SB-555P Faiz Phone known as the Faiz Phone X (ファイズフォン X(テン), Faizu Fon Ten), which retains the same function as the former's Phone Blaster Mode, to communicate with Tsukuyomi through time.

• Geiz (ゲイツ, Geitsu): Geiz's personal Ridewatch, dated 2068, which allows him to transform into Kamen Rider Geiz and convert his Time Mazine from Vehicle Mode to Robot Mode. His finishing move is the Time Burst (タイムバースト, Taimu Bāsuto).
• Bike (バイク, Baiku): An undated Ridewatch that allows Geiz to summon his own Ride Striker.
• Ghost (ゴースト, Gōsuto): Dated 2015, this Ridewatch is based on Kamen Rider Ghost (Ore Damashii). It equips Geiz with the Ghost Armor (ゴーストアーマー, Gōsuto Āmā), enabling him to levitate as well as granting him invisibility and intangibility. He can also materialize Ghost's Hoodie Ghosts as reinforcements via the Eyecon Shoulders (眼魂ショルダー, Aikon Shorudā). This form's finishing move is the Omega Time Burst (オメガタイムバースト, Omega Taimu Bāsuto).
• Cross-Z (ドラゴン, Kurōzu): Dated 2017, this Ridewatch is based on Kamen Rider Cross-Z. By setting it into the Zikan Zax, Geiz can summon a blue-colored energy dragon as part of his weapon's finishing move. This Ridewatch was initially obtained by Sento Kiryu in the final episode of Kamen Rider Build.
• Drive (ドライブ, Doraibu): Dated 2014, this Ridewatch is based on Kamen Rider Drive (Type Speed, with a design that is based on Type Tridoron). It equips Geiz with the Drive Armor (ドライブアーマー, Doraibu Āmā), enabling him to launch autonomous projectiles modeled after Drive's Shift Speed Shift Car known as the Shift Speed Speeds (シフトスピードスピード, Shifuto Supīdo Supīdo). He also gains acceleration capabilities via the Speed Tire Shoulders (スピードタイヤショルダー, Supīdo Taiya Shorudā). This form's finishing move is the Hissatsu Time Burst (ヒッサツタイムバースト, Hissatsu Taimu Bāsuto, Finisher Time Burst).
• Faiz (ファイズ, Faizu): Dated 2003, this Ridewatch is based on Kamen Rider Faiz. It equips Geiz with the Faiz Armor (ファイズアーマー, Faizu Amā), enabling him to utilize the Faiz Phone X's function of changing itself into one of two replicas of Faiz's SB-555C Faiz Shot and SB-555L Faiz Pointer known as the Faiz Shot Shot (ファイズショットショット, Faizu Shotto Shotto) and Faiz Pointer Pointer (ファイズポインターポインター, Faizu Pointā Pointā), respectively, by inputting its activation code of 5-5-5. This form's finishing move is the Exceed Time Burst (エクシードタイムバースト, Ekushīdo Taimu Bāsuto).
• Wizard (ウィザード, Wizādo): Dated 2012, this Ridewatch is based on Kamen Rider Wizard (Flame Style). It equips Geiz with the Wizard Armor (ウィザードアーマー, Wizādo Amā), granting him abilities similar to Wizard's powers. This form's finishing move is the Strike Time Burst (ストライクタイムバースト, Sutoraiku Taimu Bāsuto).

In addition to his own, Geiz is capable of using Zi-O's Ridewatches.

• Build (ビルド, Birudo): Dated 2017, this Ridewatch is based on Kamen Rider Build (RabbitTank Form). It equips Geiz with the Build Armor, granting him the Drill Crusher Crusher. He can also increase either his agility or endurance via the Fullbottle Shoulders. This form's finishing move is the Vortex Time Burst (ボルテックタイムバースト, Borutekku Taimu Bāsuto).

Geiz Myōkōin is portrayed by Gaku Oshida (押田 岳, Oshida Gaku).

Tsukuyomi

Tsukuyomi (ツクヨミ, Tsukuyomi) is a 18-year old mysterious girl from the year 2068 and like Geiz, is a member of the resistance. She disapproves of Geiz's intention to kill Sougo as it could have ramifications to the timeline, instead deciding to help Sougo avert his future of becoming Oma Zi-O. She begins to wonder if he really was the future tyrant after learning more about him, unable to believe that someone who was willing to risk his own health for a stranger would become a tyrant in the future, and convinces Geiz to spare Sougo for now while becoming house-guests at Sougo's home to keep an eye on him.

Although not a Kamen Rider herself, Tsukuyomi is in possession of her own Faiz Phone X for both self-defense and communication with Geiz through time.

Tsukuyomi is portrayed by Shieri Ohata (大幡 しえり, Ōhata Shieri).

Wars

Wars (ウォズ, Wozu) is a mysterious and shady prophet who also came from the year 2068, possessing a book of prophecies called the Ouma Kourin Reki (逢魔降臨暦, Ōma Kōrin Reki, Great Calamity Advent Calendar) and serving as the series narrator while breaking the fourth wall by talking to the audience directly during the start and the end of the episode. While surprised by Sougo's declaration of becoming a benevolent king instead of a tyrant, Wars only cares to ensure Sougo's destiny as Oma Zi-O regardless as he gave the youth his Zi-O Ridewatch and Ziku-Driver. Wars does express some distain towards Tsukuyomi, Geiz and the Time Jackers for their actions in altering the timeline, and is shown to be quite powerful himself as he was able to easily fend off Another Fourze using only one hand.

Wars is portrayed by Keisuke Watanabe (渡邊 圭祐, Watanabe Keisuke).

Oma Zi-O

Oma Zi-O (オーマジオウ, Ōma Jiō), revealed as the "Demon King" (魔王, Maō) by Tsukuyomi, is the dictator of Earth in the year 2068. Oma Zi-O's omnipotent powers convince Tsukuyomi and Geiz that the only way they can defeat him is by going to the past and changing history by intercepting Sougo whom they and the Time Jackers assume is Oma Zi-O's past self. Oma Zi-O uses a gold-colored variant of the Ziku-Driver. Like in Zi-O's base form, the word "Rider" (ライダー, Raidā) appears written on Oma Zi-O's visor in katakana, but colored red instead of magenta, and his mask is filled with a pattern comprising the kanji for King (王, Ō).

Oma Zi-O is voiced by Rikiya Koyama (小山 力也, Koyama Rikiya).

Time Mazine

The Time Mazine (タイムマジーン, Taimu Majīn) are exo-suit mecha that served as support units for the resistance. Zi-O, Geiz, and the Time Jackers possess their own Time Mazine variants for time travel.

Schwartz

Schwartz (スウォルツ, Suworutsu) is the cool-headed leader of the Time Jackers who is solely focused on creating their own Oma Zi-O. Cruel and callous, he treats Uhr and Ora as inferior underlings and often talks down to them, going as far as to taunt Uhr with chocolate. His ability to freeze time is more powerful than them both to the point where it even works against them. Unlike his younger cohorts, he throws aside subtle tactics and instead uses intimidation to force Another Rider contracts on his targets. When first meeting Sougo, Schwartz warns him that he would become Oma Zi-O as a result of his intentions of preventing it.

Schwartz is portrayed by Kentarou Kanesaki (兼崎 健太郎, Kanesaki Kentarō).

Uhr

Uhr (ウール, Ūru) is the youngest member of the Time Jackers. He is able to freeze and manipulate the flow of time and has powerful telekinetic powers, being capable of sending a car skidding across the road without touching it. When travelling through time, Uhr rides a Time Mazine that resembles Kamen Rider Ghost's Captain Ghost. He has a childish personality and manipulates his targets into forming Another Rider contracts by doing something that causes them to owe him favors such as saving their lives, something he justifies by claiming to change their lives for the better. He developed a disdain for Sougo after being rebuked by the latter who calls him out for his flawed justification. He also hates it when Schwartz looks down on him.

Despite being a human, Uhr is shown to possess superhuman powers.

Uhr is portrayed by Rihito Itagaki (板垣 李光人, Itagaki Rihito).

Ora

Ora (オーラ, Ōra) is a female member of the Time Jackers. She has a calm, laid-back deposition and, unlike her male comrades, prefers using persuasion to form Another Rider contracts on her targets, something that is easily accomplished due to her seemingly gentle demeanor. However, her patience also has its limits as shown when she got into an argument with the more childish Uhr and when Schwartz talks down to them both. Like Uhr and Schwartz, she is also capable of freezing and manipulating the flow of time.

Ora is portrayed by Ayaka Konno (紺野 彩夏, Kon'no Ayaka).

Another Riders

The Another Riders (アナザーライダー, Anazā Raidā), also known as Kaijin Riders (怪人ライダー, Kaijin Raidā), are monsters created by the Time Jackers to help them with their objectives. Each Another Rider is created when a Time Jacker uses an Another Watch (アナザーウォッチ, Anazā Wotchi) on a person, transforming them into a corrupted version of a Heisei Era Kamen Rider. It is shown that by creating the Another Riders, the Time Jackers cause the original Riders of the era to be "replaced", losing their memories due to the paradox created. The paradoxes caused by the creation of the Another Riders also permanently alters the past, meaning that the Riders will not remember their identities as Kamen Riders until they encounter Sougo in the present day. Sougo's time travelling creates his own paradoxes that causes him to be injected into their past, which causes the former Riders to regain their memories upon meeting him in the present and Ridewatches are created as a result, though said Riders remain missing from history. The only way to destroy an Another Rider for good is for Zi-O and Geiz to defeat it using a Ridewatch that corresponds to the same Rider it was based from.

• Another Build (アナザービルド, Anazā Birudo): Based on Kamen Rider Build (RabbitTank Form) with the ability to shoot flaming basketballs from his hands, as well as access the individual powers of the Rabbit and Tank Fullbottles. He was a young basketball player from 2017 whom Uhr saved from his predestined death by a vehicular accident while offering him a greater destiny as the Time Jacker's own version of Kamen Rider Build. Using his powers to seal the essence of sport athletes into Fullbottles (フルボトル, Furubotoru) and determine a suitable Best Match (ベストマッチ, Besuto Matchi), Another Build can consume them to harness both powers at once. One year later, Another Build attacked Sougo before being defeated after the latter transformed into Zi-O. However, Uhr revives him, with his power increasing after each defeat. Eventually, Zi-O and Geiz travels back to 2017 to defeat Another Build's past iteration. The basketball player then wakes up at the spot where he was supposed to die back in the year 2017 with no memories of being Another Build, though his death is still averted due to Uhr's earlier actions. The basketball player is portrayed by Taisei Mori (森 大成, Mori Taisei).
• Another Ex-Aid (アナザーエグゼイド, Anazā Eguzeido): Based on Kamen Rider Ex-Aid (Action Gamer Level 2) with the ability to perform inhuman feats based on platform games, as well as divide into Game Worlds (ゲームの世界, Gēmu no Sekai) and summon Bugster Virus A (バグスターウイルスA, Bagusutā Uirusu Ē) as footsoldiers. He is transformed from a man named Iida (飯田), who creates the "game that cannot be cleared by anyone" (誰もクリアしたことのないゲーム, Dare mo kuria shita koto no nai gēmu) with the purpose of capturing young boys who could be compatible heart donors to save his son, Keisuke (ケイスケ), with his desperation and hatred for doctors preventing him from realizing his own cruelty in doing such an act. After being defeated by Zi-O in 2016, Iida's son is put under Hiiro Kagami's care to ensure that his son could be cured before his disease became so advanced that only a heart transplant could save him, which also voided his initial descent into villainy. Iida is portrayed by Takashi Kodama (児玉 貴志, Kodama Takashi)
• Ryūichi Sakuma (佐久間 龍一, Sakuma Ryūichi): An Amanogawa High School student who previously became Another Faiz in 2003 through Ora's influence to revive his childhood friend Karin Yamabuki (山吹 カリン, Yamabuki Karin) and prolong her life by extracting bioenergy from girls who share Karin's age and birthdate. By the time Sakuma attends AGHS, he lost the ability to become Another Faiz with Schwartz giving him the ability to become Another Fourze with use of the Core Switch. But Sakuma did not expect Karin to enlist the aid of Masato, leading to him facing Sougo with the Fourze Ridewatch in 2018 and Geiz with the Faiz Ridewatch in 2003. After being defeated in both timelines, he finally realized he was hurting Karin more than helping her and was forced to accept her death, though he also have to live the rest of his life with full knowledge of his sins. Thankfully, the defeat of his 2003 and 2011 selves also negates all the deaths and disappearances he had caused. Ryūichi Sakuma is portrayed by Atom Mizuishi (水石 亜飛夢, Mizuishi Atomu).
  • Another Fourze (アナザーフォーゼ, Anazā Fōze): Based on Kamen Rider Fourze (Base States), he can absorb or supply bioenergy while using the switches on its belt to summon Energy Modules (エネルギーモジュール, Enerugī Mojūru) based on the Astroswitch technology's Fourze Modules.
  • Another Faiz (アナザーファイズ, Anazā Faizu): Based on Kamen Rider Faiz, this form was unveiled upon the destruction of Another Fourze, he is also able to absorb bioenergy. This was his original Another Rider form, one he managed to maintain up to 2018 where it was about to die out, only to emerge when his Another Fourze form was destroyed.
• Another Wizard (アナザーウィザード, Anazā Wizādo): Based on Kamen Rider Wizard (Flame Style). Hayase is portrayed by Zuimaro Awashima (粟島 瑞丸, Awashima Zuimaro).

Sento Kiryū

Sento Kiryū (桐生 戦兎, Kiryū Sento), born Takumi Katsuragi (葛城 巧, Katsuragi Takumi), is a scientist who is the main character and titular rider of Kamen Rider Build (仮面ライダービルド, Kamen Raidā Birudo). Originally from an alternate reality where Japan was divided into three regions by the actions of an alien being known as Evolto, Sento caused his reality to be absorbed in the 'prime' Kamen Rider universe after using the Pandora Box to erase Evolto's existence from Earth's history. Due to Another Build's creation, Sento lost his memories as Build before Sougo arrived to nascita to seek his help. Sougo's presence causes the Build Ridewatch to appear in Sento's pocket as he and Ryūga regain their memories. The two would help Sougo by giving him their Ridewatches before Sougo and Geiz time travels back to their world in 2017 to defeat Another Build's past iteration while establishing a bootstrap paradox.

• Year 2017: Sento encounters a time-displaced Sougo on November 30, 2017 while he and Ryūga were still in their reality, Sento deducing Sougo to be from the future. Both of them would encounter Sougo again, this time with Geiz, as the four of them fought together against Another Build. During the fight, Sento gradually loses his powers and memories as a Kamen Rider to the point of referring to himself as Takumi. To prevent Sento's past from being permanently altered, Sougo gives him and Ryūga the blank Ridewatches that they would give to Sougo in 2018.

Atsuhiro Inukai (犬飼 貴丈, Inukai Atsuhiro) reprises his role as Sento Kiryū.

Ryūga Banjō

Also returning from Kamen Rider Build, Ryūga Banjō (万丈 龍我, Banjō Ryūga) is a former professional fighter who can transform into Kamen Rider Cross-Z (仮面ライダークローズ, Kamen Raidā Kurōzu). Like Sento, he was originally from an alternate reality where Japan was divided into three regions by the actions of an alien being known as Evolto until Sento merged their reality with the 'prime' Kamen Rider universe. Due to Another Build's creation, Ryūga lost his memories as Cross-Z before Sougo arrived to nascita to seek Sento's help. Sougo's presence causes the Cross-Z Ridewatch to appear in Ryūga's pocket as he and Sento regain their memories. The two would help Sougo by giving him their Ridewatches before Sougo and Geiz time travel back to their world in 2017 to defeat Another Build's past iteration.

• Year 2017: Sento encounters a time-displaced Sougo on November 30, 2017 while Ryūga and Sento were still in their reality. Both of them would encounter Sougo again, this time with Geiz, as the four of them fought together against Another Build. During the fight, Ryūga gradually loses his powers and memories as a Kamen Rider. To prevent Ryūga's past from being permanently altered, Sougo gives him and Sento the blank Ridewatches that they would give to Sougo in 2018.

Eiji Akaso (赤楚 衛二, Akaso Eiji) reprises his role as Ryūga Banjō.

Emu Hojo

Emu Hojo (宝生 永夢, Hōjō Emu) is a young doctor and a genius video gamer with the assistance of Parado, who is the main character and titular rider of Kamen Rider Ex-Aid (仮面ライダーエグゼイド, Kamen Raidā Eguzeido). He initially attacked Zi-O and Geiz after mistaking them for enemies. Like Build and Cross-Z, he loses his memories of being Kamen Rider Ex-Aid after the creation of Another Ex-Aid, but unlike the former two, he was able to retain some of his previous memories,. He later gives the Ex-Aid Ridewatch to Sougo, entrusting him with his powers

• Year 2016: Encountering Another Ex-Aid, Emu transforms into Kamen Rider Ex-Aid and assists Sougo and Geiz by fending off the Bugsters summoned by his twisted counterpart until his powers faded away before witnessing Zi-O defeating Another Ex-Aid, with a moment of seeing Zi-O fourth wall breaks on using the Critical finisher background as part of his finishing move in confusion. He is then given a blank Ridewatch to connect him with Sougo in the future.

Hiroki Iijima (飯島 寛騎, Iijima Hiroki) reprises his role as Emu Hojo.

Hiiro Kagami

Also returning from Kamen Rider Ex-Aid, Hiiro Kagami (鏡 飛彩, Kagami Hiiro) is a young prodigy surgeon who can transform into Kamen Rider Brave (仮面ライダーブレイブ, Kamen Raidā Bureibu). He shows suspicion towards Sougo and company when they sought out Emu/Ex-Aid, and later reveals that Iida's son could have been cured easily had he been brought to him earlier. Thanks to Sougo and Geiz's actions in tweaking the past, Hiiro is revealed to have managed to cure Iida's son of his heart condition before it advanced to the point where a transplant is necessary.

Toshiki Seto (瀬戸 利樹, Seto Toshiki) reprises his role as Hiiro Kagami.

Chuta Ohsugi

Returning from Kamen Rider Fourze, Chuta Ohsugi (大杉 忠太, Ōsugi Chūta) is a geography teacher at Amanogawa High School who serves as advisor to the Kamen Rider Club. He is entrusted with the Fourze Ridewatch by Gentaro Kisaragi, and gives it to Sougo and Geiz.

Takushi Tanaka (田中 卓志, Tanaka Takushi) reprises his role as Chuta Ohsugi.

Daita Kondo

Returning from Kamen Rider × Kamen Rider Wizard & Fourze: Movie War Ultimatum, Daita Kondo (近藤 大太, Kondō Daita) is a member of the Kamen Rider Club.

Kazuyoshi Nakazawa (中澤 兼利, Nakazawa Kazuyoshi) reprises his role as Daita Kondo.

Chikao Nezu

Also returning from Kamen Rider × Kamen Rider Wizard & Fourze: Movie War Ultimatum, Chikao Nezu (根津 誓夫, Nezu Chikao) is a member of the Kamen Rider Club.

Yuya Hara (原 勇弥, Hara Yūya) reprises his role as Chikao Nezu.

Takumi Inui

Takumi Inui (乾 巧, Inui Takumi) is a passive loner who is the main character of Kamen Rider 555. The main wearer of the Faiz Gear which allows him to transform into the titular Kamen Rider Faiz (仮面ライダーファイズ, Kamen Raidā Faizu), he is also an Orphnoch, a human who had evolved into a monster. In Takumi's case, he is the Wolf Orphnoch (ウルフオルフェノク, Urufu Orufenoku). Originally supposed to have died/removed from existence during the events of "Kamen Rider Drive", due to the machinations of the Time Jackers, he survived and never became an Orphnoch as all Orphnoches were erased from history upon the creation of Another Faiz. In 2018, learning of Masato's kidnapping of Karin Yamabuki, he goes after him to find out why and learns about the situation regarding Karin and Sakuma. He regained the memories of his original life and fate after meeting Sougo and gives the Faiz Ridewatch to Geiz.

Kento Handa (半田 健人, Handa Kento) reprises his role as Takumi Inui.

Masato Kusaka

Also returning from Kamen Rider 555, Masato Kusaka (草加 雅人, Kusaka Masato) is a selfish, manipulative young man with an extreme hatred for all Orphnochs, including Takumi. He is the main wearer of the Kaixa Gear which allows him to transform into Kamen Rider Kaixa (仮面ライダーカイザ, Kamen Raidā Kaiza). Originally supposed to have died back in 2003 at the hands of the Horse Orphnoch, the timeline was altered with Masato's death and status as a Rider averted, though he still treats Takumi with hostility. He met Amanogawa High School student Karin Yamabuki who asked for his help in stopping Sakama by kidnapping, and later killing her, which attracts the attention both Sougo's group and Takumi. Unlike all his previous appearances which portrayed him as a villain, Masato was shown in a more positive light in this series as he risked his life to find a way to stop Sakuma's murder spree without having to kill Karin despite her desperate request.

Kōhei Murakami (村上 幸平, Murakami Kōhei) reprises his role as Masato Kusaka.

Kosuke Nito

Returning from Kamen Rider Wizard, Kosuke Nito (仁藤 攻介, Nitō Kōsuke) is a young archaeologist who discovered the Beast Driver, which he uses to transform into Kamen Rider Beast (仮面ライダービースト, Kamen Raidā Bisuto).

Tasuku Nagase (永瀬 匡, Nagase Tasuku) reprises his role as Kosuke Nito.

Kuroto Dan

Also returning from Kamen Rider Ex-Aid, Kuroto Dan (檀 黎斗, Dan Kuroto) is one of the orchestrators of the Bugster virus outbreak and the second CEO of Genm Corp. who can transform into Kamen Rider Genm (仮面ライダーゲンム, Kamen Raidā Genmu).

Tetsuya Iwanaga (岩永 徹也, Iwanaga Tetsuya) repirses his role as Kuroto Dan.