Icon-zi-o.png This article is about a/an monstrous Rider in Kamen Rider Zi-O.

"No! I have to save you! I swear, I'll save you Karin!"
―Ryuichi Sakuma as Another Fourze.[src]

Ryuichi Sakuma (佐久間 龍一 Sakuma Ryūichi) transformed into two Another Riders, Another Fourze (アナザーフォーゼ Anazā Fōze), derived from Kamen Rider Fourze Basestates, and Another Faiz (アナザーファイズ Anazā Faizu), derived from Kamen Rider Faiz.

Character History

"I'm afraid I have some bad news for you. But there's good news, too. After this scene here, you'll blame yourself for the rest of your life, but if you make a contract with me, you can save this girl."


In 2003, Ryuichi was a student at Ryusei School and the boyfriend of Karin Yamabuki. When Karin was killed in a car accident, the Time Jacker Ora appeared before Ryuichi and offered him an Another Rider contract that would save Karin. He immediately accepted and was transformed into Another Faiz, causing Kamen Rider Faiz's existence and history to disappear. Using the power of Another Faiz, Ryuichi kidnapped and transformed female high school students sharing Karin's age and astrological sign (Libra) into life energy that would keep Karin alive, making her transfer to different schools whenever his actions became too conspicuous.


In 2011, Ryuichi's power as Another Faiz began to fade, causing him great distress. Swartz, another Time Jacker, came to him and granted him another contract that warped Ryuichi into Another Fourze, erasing Kamen Rider Fourze's existence. Renewed and upgraded, Ryuichi continued to kidnap girls and keep Karin alive.


In 2018, while Sougo Tokiwa, Geiz Myoukouin, and Tsukuyomi were investigating the disappearances caused by Ryuichi, currently at Amanogawa High School, Masato Kusaka attempted to kill Karin by throwing her off of a roof, drawing the attention of Sougo, Geiz, and Tsukuyomi. Ryuichi caught and saved Karin, but was confronted by Sougo and Geiz, and fled after a brief fight with Zi-O and Geiz BuildArmor.

Sougo and Geiz later traveled to 2011 to stop Ryuichi's first attack as Another Fourze, and Ryuichi was defeated by Zi-O FourzeArmor. However, his original contract as Another Faiz reflected the defeat and allowed Ryuichi to maintain his Another Fourze powers. Switch On! 2011

In 2018, Karin stopped Ryuichi from taking another victim, tired of surviving off of the stolen lives of others. Masato Kusaka then appeared and again attempted to kill Karin, to relieve her of the life imposed on her by Ryuichi. Ryuichi retaliated by attempting to choke Kusaka to death, but was thwarted by Takumi Inui, and fled soon after. With the situation explained by Kusaka, Geiz traveled to 2003 with the Faiz Ridewatch to stop Ryuichi's first attack as Another Faiz, while Sougo stopped his first attack as Another Fourze in 2011. Ryuichi was simultaneously defeated as Another Faiz by Geiz FaizArmor, and as Another Fourze by Zi-O FourzeArmor while Karin pled with him to let her die. At last, Ryuichi understood and accepted that his power was only making Karin suffer even more. With one final embrace, he bid farewell to the one he loved as she disintegrated out of existence. 555・913・2003


Sakuma being attacked by Another Ex-Aid (Hiryu Kakoagwa).

Few months later, it was shown that Ryuichi graduated high school and was now an astronomer at the Yotsuba Observatory. He noticed the strange phenomenon of Regulus shining brighter than it usually did and earlier in the year than normal while using the telescope the previous night and was on the phone with a colleague at another observatory to confirm his findings and try to figure out what was going on. He was then attacked by Hiryu Kakogawa, revealing he had no memory of being Another Fourze and Faiz while attacked by him. His power of Another Faiz was extracted from him and Kamen Rider Geiz intervened before Hiryu could obtain Another Fourze's power. Sougo stayed by Ryuichi's side until he regained consciousness when the fighting ended to make sure he was okay.Another Zi-O 2019


Another Fourze

Another Fourze

Another Fourze opened his eyes and mouth

―Transformation announcement[src]
  • Height: 200 cm
  • Weight: 95 kg
  • Creator: Swartz
  • Year of Origin: 2011
  • Position of year: Left shoulder
  • Name and position: "FOURZE"; Right shoulder.
Powers and Abilities
  • Lifespan Manipulation: Like Another Faiz, Another Fourze is able to absorb people and convert them into energy, which can then be used to revive the deceased. However, the revived subject can only use energies made from people sharing their age and astrological sign and must receive these "life injections" regularly to maintain their form.
  • Energy Modules (エネルギーモジュール Enerugī Mojūru): Another Fourze is able to project energy copies of Fourze Modules by pressing the buttons on its buckle(Where the Fourze Driver would be).[1]
  • Self-Resurrection: As with Another Riders, Fourze cannot be destroyed unless with the Ridewatch that correspond to his Rider Powers. With the power of Another Faiz resurfaces, Another Fourze can revive himself even when the Ridewatch of same power was used to defeat him.
  • Fourze and Faiz Ridewatches: As Ryuichi is two Another Riders in one host, he can only be defeated when both users of Fourze and Faiz Ridewatches defeated him in the era that he was created.

Appearances: Zi-O Episodes 5-6

Another Faiz

Another Faiz

―Transformation announcement[src]
  • Height: 186.0 cm
  • Weight: 91.0 kg
  • Creator: Ora
  • Year of Origin: 2003
  • Position of year: Left shoulder
  • Name and position: "FAIZ"; Right shoulder.
Powers and Abilities
  • Lifespan Manipulation: Another Faiz is able to absorb people and convert them into energy, which can then be used to revive the deceased. However, the revived subject can only use energies made from people sharing their age and astrological sign and must receive these "life injections" regularly to maintain their form.
  • Rider Kick: Another Faiz can shroud his entire body with red aura to perform his variation of Faiz Blaster's Crimson Smash.
  • Fourze and Faiz Ridewatches: As Ryuichi is two Another Riders in one host, he can only be defeated when both users of Fourze and Faiz Ridewatches defeated him in the era that he was created.
  • Power Decline: Another Riders' lifespan are limited and would eventually fade away. Overusing their power would accelerate this proccess,[2] as seen when Another Faiz's power began to fade after 7 years. Their lifespan can be prolonged by taking a new Another Riderwatch, gaining a new Another Rider form from it if said Ridewatch is different. 555・913・2003

Appearances: Zi-O Episodes 5-6


Behind the Scenes


Sakuma is portrayed by Atomu Mizuishi (水石 亜飛夢 Mizuishi Atomu), who previously portrayed Crow in Garo: Makai no Hana, and later went on to portray Shiguru OshikiriIcon-crosswiki.png/KiramaBlue in Mashin Sentai KiramagerIcon-crosswiki.png.

As Another Fourze and Another Faiz, his suit actor is Eitoku (永徳). Meanwhile, the announcements made from Another Fourze's use of Energy Modules are recycled from the Fourze Driver announcements.

Concept Art

Another Fourze and Another Faiz were designed by Tamotsu Shinohara (篠原 保 Shinohara Tamotsu).


  • Since Another Faiz is meant to be transformed from Another Fourze, both of their undersuits sport identical design.
  • Ryuichi is the anithesis of Fourze and Faiz in the fact that he destroyed people's dreams, killing them by taking their life energy out of selfishness while the real Faiz always protected dreams selflessly despite having none of his own and ultimately draining his own life away to keep the world safe. His antithesis of Fourze is that Ryuichi values only what he wants and sometimes is not considerate of anyone else's feelings, not even Karin's as she wants to die. Fourze would go out of his way to try and help someone and befriend them, always trying to be considerate of others even if they don't realize it, and even willing to sacrifice his own powers.
    • Ryuichi's personality is most similar to the Secondary Riders, Masato Kusaka & Ryusei Sakuta:
      • With Masato, the two were former Ryusei School students who possessed an unhealthy relationship with their love interest (For Kusaka was Mari Sonoda), as well as willing to hurt others under the belief for her sake.
      • With Ryusei, both became Riders for the intent of rescuing a loved ones (For Ryusei was Jiro Iseki) from death, even willing to commit heinous acts like murder, before realizing the error of their ways from the person they were trying to save.
  • The horns on Another Fourze's head resembled Kamen Rider Specter's Wisp Horns. In fact, in Kamen Rider Ghost: Legendary! Riders' Souls!, Specter uses the power of Fourze Damashii to destroy Sagittarius Nova.

Another Faiz rises from the fire.png

  • The reveal of Another Faiz transitions from Another Fourze signifies two similarities of their representative series and Riders:
    • Both of their series are related to school compounds (Ryusei School and Amanogawa High) and several of the respective monsters came from (former) students of said school.
    • Another Fourze's defeat and later on emergence as Another Faiz is based on Dragon Orphnoch's evolution and those of Zodiarts into Horoscopes, including their later evolution into Supernova.
    • Ryuichi is also similar to Ryusei Sakuta/Kamen Rider Meteor. Both of them made a deal with one of their series' respective villains in hopes of saving their friend/loved ones. Unfortunately, their atrocity were all in vain as the characters in question reject their will to live.
  • Sakuma being the host of two monsters in a two-parter episode parallels Masahiro Nabeshima as Mirage and Square Smash from Kamen Rider Build.
  • Despite serving as an antithesis to Kamen Rider Fourze, Another Fourze spontaneously performs Gentaro's "Space is Here!" (宇宙キター! Uchū Kitā!) pose upon being created by Swartz, though he does not say the line. This continues a recurring gag of characters with clashing personalities being compelled to evoke Gentaro Kisaragi when assuming the power of Fourze, following Specter as Fourze Damashii in Fourze Chapter, and Zangetsu as Fourze Arms in Kamen Rider Gaim: Sengoku Battle Royale.
  • Ryuichi showing symptoms of declining due to short lifespan pays homage to the Orphnochs and Horoscopes.
  • Although the red Photon Blood-like veins were meant to represent Faiz, it also resembles the Zodiarts' trademark constellation lines.
  • Another Faiz is the first in show Another Rider to be based on a Rider from the First Phase of the Heisei Era.


See also


Sougo Tokiwa (Over Quartzer) - Geiz Myokoin - Woz (black, white, red) - Tsukuyomi
Other Sougo Tokiwa variations
Ohma Zi-O - Mirror World - Leader of Quartzer - B - C - D - E - F - Robot Sougo - True Sougo
Future Kamen Riders
2022 (Rentaro Kagura - Isamichi Konjo) - 2040 (Mondo Douan) - 2121 (Rento Makina) - Kamen Rider Ginga
Rider Time Ryuki Riders
Ishihashi - Tozuka - Kimura - Ishida - Abyss - Odin
Another World Riders
G4 - Fuma - Dark Ghost - Rey - Katsumi Daido - White Woz - Yuuki
Other Riders
G3 Team - Shun Kageyama (Worm)
Movie-exclusive Riders
SOUGO Tokiwa - Kagen - Jogen - Soreo Hiden
Stageshow-exclusive Riders
Hiryu Kakogawa - Red Woz
Transformation Devices
Ziku-Driver - Ohma Zi-O Driver - Beyondriver - Miraidriver (Shinobi, Hattari, Quiz, Kikai, Ginga) - NeoDecadriver - NeoDiendriver - K-Touch 21
Ridewatches - Miridewatches- Ridewatch Holder - Ridewatch Daizer - Faizphone X - Taka Watchroid - Kodama Suika Arms
Zikan Girade - Zikan Zax - Ride HeiSaber - Zikan Despear - Saikyo Girade - Zikan Jaclaw - Barlckxs' Sword
Ride Striker - Time Mazine - Dai Mazine - Karakuri Robos (Kurogane Oogama - Unnamed Wasp-based Karakuri Robo)
Rider Armors - Oma Advent Calendar - Future Note - Time Finishers
9 5 DO: Geiz Myokoin - Tsukuyomi - Junichiro Tokiwa
Futaros - Ataru Hisanaga - Shingo Hisanaga - Iroha Kagura - Master Gamano - Sara - Ms. Sailor - Oda Nobunaga - Clara Steinbelt - Gyuzo - Pietro - Resistance Captain
Kuuga: Yusuke Godai
Agito: Shoichi Tsugami - Takahiro Omuro
Ryuki: Shinji Kido - Dark Shinji - Ren Akiyama - Takeshi Asakura - Miyuki Tezuka - Jun Shibaura - Goro Yura
555: Takumi Inui - Masato Kusaka
Blade: Kazuma Kenzaki - Hajime Aikawa
Hibiki: Hitoshi Hidaka - Tomizo Todayama - Kyosuke Kiriya
Kabuto: Soji Tendo - Arata Kagami - So Yaguruma
THE FIRST/THE NEXT: Takeshi Hongo - Katsuhiko Yano - Shiro Kazami
Den-O: Ryotaro Nogami - Yuto Sakurai
Kiva: Wataru Kurenai - Jiro
Decade: Tsukasa Kadoya - Daiki Kaito - Yusuke Onodera - Natsumi Hikari
G: Goro
W: Philip & Shotaro Hidari - Ryu Terui
OOO: Eiji Hino - Michal Minato - Akira Date - Shintaro Goto
Fourze: Gentaro Kisaragi
Wizard: Haruto Soma - Kosuke Nitoh
Gaim: Kouta Kazuraba - Kaito Kumon - Takatora Kureshima
Drive: Shinnosuke Tomari - Go Shijima - Chase - Brain
Ghost: Takeru Tenkuji - Makoto Fukami
Kuuga (manga): Yusuke Godai
Amazons: Haruka Mizusawa - Jin Takayama
Ex-Aid: Emu Hojo - Hiiro Kagami - Kiriya Kujo - Kuroto Dan - Masamune Dan
Kamen Sentai Gorider: Aka-Rider - Ao-Rider - Ki-Rider - Momo-Rider - Mido-Rider
Build: Sento Kiryu - Ryuga Banjo - Kazumi Sawatari - Gentoku Himuro - Evolto
Zero-One: Aruto Hiden - Isamu Fuwa - Yua Yaiba - Jin - Horobi
Chuta Ohsugi - Daita Kondou - Chikao Nezu - Hina Izumi - Shibuya Hachioji - Narita Kisarazu - Misora Isurugi - Master of Fumen - Owner - Momotaros - Urataros - Kintaros - Ryutaros - Eri Ogawa - Daisuke Okubo - Amane Kurihara - Mana Kazaya - Riki - Ramon - Deneb - Krim Steinbelt - Takeshi Kinashi - Izu - Shesta - Jun Fukuzoe - Sanzo Yamashita - Narutaki
Swartz - Heure - Ora
Movie Exclusive
Tid - Finis
SOUGO Tokiwa - Kagen - Jogen - Woz
Another Build - Another Ex-Aid - Another Fourze - Another Faiz - Another Wizard - Another OOO - Another Gaim - Another Ghost - Another Double - Another Den-O - Another Kuuga - Another Shinobi - Another Quiz - Another Ryuga - Another Kikai - Another Zi-O (II) - Another Ryuki - Another Blade - Another Agito (troops) - Another Hibiki - Another Kiva - Another Kabuto - Another Drive - Another Decade
Movie-exclusive Another Riders
Another Zero-One - Another 1 - Another Diend
Stageshow-exclusive Another Riders
Another Rider - No Rider - Another Ohma Zi-O
Other Villains
Kasshine - Humanoise - Worms - Elementary Inves - Trilobite Magia - Battle Magia
Niji no Hebi: Yaminin - Dustards
Community content is available under CC-BY-SA unless otherwise noted.