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

"Now, enjoy your hell!"
―Eternal's catchphrase
"Every future eventually will become the past!"
―Eternal to Aqua

Katsumi Daido (大道 克己 Daidō Katsumi) is a resident of an Another World where he defeated Kamen Rider Double as Kamen Rider Eternal (仮面ライダーエターナル Kamen Raidā Etānaru).


Early Life

Main article: Katsumi Daido#Early Life

Attack on Futo

According to Tsukasa Kadoya, due to the creation of Another World, Katsumi (despite losing his comrades) defeated Philip and Shotaro Hidari during their battle on the Futo Tower and his mission to destroy the Museum became successful.

Kamen Rider Zi-O

2019: Eternal Party

Kamen Rider Eternal vs Zi-O

"You want to know the name of Death? You will know it...When you are in Hell! Daido Katsumi!"
―Daido's words of introduction to Sougo

Katsumi Daido was brought to the main universe by Swartz to fight Sougo Tokiwa. After introducing himself, he transformed into Kamen Rider Eternal and gained the upper hand fighting Zi-O. However, in the middle of the fight, Zi-O was saved by Tsukasa.

Later on, he engaged in battle with Kamen Rider Aqua. Aqua managed to take the fight underwater to gain an advantage. This was short-lived, as Eternal generated an underwater cyclone to blow Aqua back on land. He then proceeded to overpower the future Kamen Rider.

2019: Operation Woz

"An interesting wind blew, didn't it?"
"I took advantage of your powers... sorry."
"Nah. Thanks to you, you destroyed a world where only I was revived. Now I can be where my comrades are.
―Daido's final words to Sougo before fading away

However, before Daido could land a finishing blow, Woz Ginga Taiyou saved both Tsukuyomi and Minato and successfully fled. However, due to White Woz's (also summoned by Swartz from Another World) Future Note, Daido, as Eternal, was set to face Minato once more. Sougo as Zi-O interfered with their battle, and later Kamen Rider Yuuki (also summoned by Swartz from Another World) joined forces with Eternal. At the same time, Swartz and White Woz transported Black Woz and Tsukuyomi into the Another World, trapping them there. Zi-O, outraged, attempted to attack Swartz, but Eternal blocks the slash and the two continued their fight. Eternal used his Maximum Drive and overpowered Zi-O with it.

Eternal's finisher destroys multiple Another Worlds.

Zi-O later assumed W armor and managed to fight Eternal on a more equal ground, trading blows with him. Daido also chose to power himself up by activating the Zone Gaia Memory's Maximum Drive to enter Strengthening Armament mode and delivered a powerful Rider Kick to Zi-O. However, thanks to White Woz's advice beforehand, Sougo managed to teleport both him and Eternal to Another World using the Zi-OTrinity Ridewatch. Zi-O, now in Trinity form, then redirected Eternal's kick to the dimension itself, and the force of his attack is potent enough to destroy several Another Worlds, including the one where Geiz is being trapped, therefore returning him, and Swartz's other victims back to reality.

Katsumi's good gesture towards Sougo before his erasure

Daido cancelled his transformation, he remarked that "an interesting wind blew past here". Sougo apologized for having taken advantage of his power in such a manner. However, Daido instead gave Sougo his thanks, because by destroying the world where only he was revived, he could reunite with his fallen comrades. He finally faded away from reality, but not before giving Sougo one last thumbs-up instead of his trademark thumbs-down.

Kamen Rider Eternal

Blue Flare

Kamen Rider Eternal Blue Flare

Kamen Rider Eternal Blue Flare (Without Eternal Robe)

"Eternal! (Energetic drumming)"
―Transformation announcement[src]
  • Height: 205 cm.
  • Weight: 95 kg.

Ability Perimeters:

  • Punching Power: 7 t.
  • Kicking Power: 12 t.
  • Maximum Jump Height: 150 m.
  • Maximum Running Speed: 100 m. per 3 sec.

Through the Lost Driver and the Eternal Memory, Katsumi transforms into Kamen Rider Eternal. Eternal's Maximum Drive with the Eternal Edge is the Eternal Requiem (エターナルレクイエム Etānaru Rekuiemu), a power wave that renders the powers of all other Gaia Memories useless. Like most Riders in Kamen Rider W, Eternal has an English letter motif - in this case the letter 'E'. Katsumi originally transformed using the standard Eternal Memory, but eventually abandoned it in favor of the T2 version. Eternal is also adorned with a black Eternal Robe (エターナルローブ Etānaru Rōbu) cape after transformation.

In this mode, he is able to execute the Eternal Requiem (エターナルレクイエム Etānaru Rekuiemu) Maximum Drive utilizing the Eternal Edge. In Kamen Rider Zi-O, he is also shown to be capable of performing an unnamed Rider Slash.  In addition to the Maximum Slots on the Lost Driver and the Eternal Edge, Eternal Blue Flare has a series of Maximum Slots on belts around his chest, right arm, and left leg, for a total of 26 for every T2 Gaia Memory.

This form is called Eternal's Blue Flare (ブルーフレア Burū Furea) form, as revealed in Kamen Rider W Returns, which is more powerful than the incomplete Red Flare form.

While having significantly lower states than most Riders appearing in Zi-O (including guests), Eternal, interestingly, is able to gain upper hand when fighting Aqua and Zi-O (even in his Trinity Form briefly). As this form's Rider Kick is able to destroy many Another Worlds, it is possible that its stats might beyond this.

Appearances: Zi-O Episodes 45 & 46

Strengthening Armament

Strengthening Armament Mode

"Zone! Maximum Drive!"
―Transformation announcement[src]
  • Height: 205 cm.
  • Weight: 97 kg.

By filling all 26 of his Memory Slots through the T2 Zone Memory, Eternal enters his Strengthening Armament (強化武装 Kyōka Busō)[1] mode. This form is also called Strongest Form, and Gaia Memories Full Equipped Form[2].

In this mode, he is able to absorb the X-Bicker's energy to produce the Eternal Wave to execute the Never Ending Hell (ネバーエンディングヘル Nebā Endingu Heru) Maximum Drive utilizing the Eternal Edge. In Kamen Rider Zi-O, by drawing the energy of all T2 Gaia Memories and focusing it into his leg, Eternal can also execute a Rider Kick. The power of the Kick is potent enough to destroy several of Swartz's Another Worlds

However, the Strengthening Armament is only usable in Blue Flare form.

Appearances: Zi-O Episode 46


Behind the scenes


This version of Katsumi Daido is also portrayed by Mitsuru Matsuoka (松岡 充 Matsuoka Mitsuru) of SOPHIA, who also performed W and Cod-E ~E no Angō~, the theme songs of Kamen Rider W Forever: A to Z/The Gaia Memories of Fate and Kamen Rider W Returns: Kamen Rider Eternal respectively, and also previously portrayed his original role in the two respective films.[3] He also performed the opening theme of Kamen Rider Drive, as well as voicing Kamen Rider 4 in D-Video Special: Kamen Rider 4.


  • In the original timeline, Katsumi Daido is an anti-hero when he saves Mina and defeats Eyes Dopant before he becomes a villain when he witnesses Mina’s “death”. It drives himself into madness and he goes on to terrorize Fuuto until his defeat by Kamen Rider Double. This Another World version of Katsumi Daido is a villain when he is sent by Swartz to battle Kamen Rider Zi-O and his team, until his defeat. He later gives Sougo a good gesture, signifying that he becomes better at his last moments before he vanishes. Also unlike the rest of the evil Kamen Riders from Another World, this version of Daido eventually accepts his defeat graciously.
  • Even though he came from a world where he defeated Double, it seems he knew and acknowledges that there is a world where he would be defeated by Double, as when Sougo mentioned it before using the Double Ridewatch. 2019: Operation Woz



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
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