Kamen Rider Wiki
Kamen Rider Wiki
Icon-w.png This article is about a Villain in Kamen Rider W.

Ryubei Sonozaki (園咲 琉兵衛, Sonozaki Ryūbē), also known for his Dopant identity as Terror Dopant (テラー・ドーパント, Terā Dōpanto), is one of the main antagonists in Kamen Rider W. He was the head of the Sonozaki Family and leader of the Museum.



Before his son Raito Sonozaki's death, Ryubei was an archaeologist who bought the grounds his estate was built on after finding deposits of fossils and relics that eventually form the collection in the Futo Museum. It was then he found a point where the planet's consciousness dubbed the "Gaia Memory" resides and brought his family to see it.

However, when his son Raito fell into the "fountain" of the Gaia Memory and died, but was somehow resurrected by the planet's powers, Ryubei began his plan for the Gaia Impact and used the Evil Tail charm he acquired overseas as a means to overcome the fear that would go with sacrificing his own family to achieve it. As a result, Ryubei went mad and saw the entire city of Futo as his kingdom and he refuses to let his vision of it be ruined, even by his own wife and children.

Part in Story

Ryubei spends most of the series in the Sonozaki Manor rarely having any part in most Dopant crime waves. He appears as the Terror Dopant usually when necessary and involving the Museum affairs. When the Gaia Impact plan commences, he invites his family (mainly Saeko and Shroud) to beg for forgiveness as Wakana will become all-powerful through the Gaia Impact, but Saeko refuses and fights against her sister instead while Shroud takes her leave after giving a hint to Philip on stopping the Gaia Impact. He then sacrifices Raito (Philip) once more into the Gaia Memory to make his daughter Wakana one with the Earth. Just when it seemed the Gaia Impact was going to succeed, Shotaro and Akiko appeared as they confronted him about the Evil Tail which alarmed Ryubei somewhat. After denying their claims about his own fears, Ryubei transformed into the Terror Dopant as he tried threatening them into giving the Evil Tail only to see Shotaro overcome his fear and transform into Double, thus bringing Philip's conscience back which caused a glitch in Wakana and the Gaia Impact. Shocked and angered at Shotaro's actions he then fought Double until the Revolgarry and Accel arrived to assist Shotaro and Philip.

While Kamen Rider Accel as the AccelTurbuler destroys his Terror Dragon, the Xtreme Memory retrieved Philip`s body from the aspects of the Gaia Memory in Claydoll Xtreme to transform Double from CycloneJoker into CycloneJokerXtreme in order to defeat the Terror Dopant and destroy the Terror Memory, along with most of the Sonozaki estate. With Ryubei's mind still broken from years of planning, he enters the still burning ruins of his home, glad that he had finally initiated the Gaia Impact. He dies in the blaze, thinking of the good times he had with his family before he discovered the Gaia Memory. He later appears with most of his family members and say their goodbyes to Philip before disappearing.

Kamen Rider Ghost: Legendary! Riders' Souls!

Ryubei is resurrected as the Terror Dopant and summoned by Frey. He appears before Makoto Fukami and Onari who are out on patrol after Freya told the Mysterious Phenomenon Institute to gather the Kamen Riders' Ghost Eyecons. Voicing his query that the Earth could have decided Makoto was one of the chosen few, Ryubei proceeds to fight the young man once he transforms into Kamen Rider Specter, engaging him in a brief skirmish before he paralyzes him by his power of inducing intense fear. However, Specter soon enough manages to overcome the terror, explaining to Ryubei that Takeru saved him from giving in to despair before, swearing that he would never give into it again for his sake and that of his sister Kanon, going on to say that anyone who would bring sorrow upon this city that Kanon loves would have to answer to him. This grants Specter a Joker Memory, from which he unseals the W Parka Ghost, creating the W Ghost Eyecon which he uses to assume Double Damashii, granting him the power of Kamen Rider Double and allowing him to turn the tide against and quickly destroy the Terror Dopant, who notes that he shall return to his family now that he has died again. W Chapter

Ultimately, it was revealed that Ryubei and the other past enemies were brought back in order for the Kamen Riders to gather the Kamen Rider Ghost Eyecons so they could defeat the monster Xibalba, as Frey and Freya secretly planned together. OOO Chapter


Ryubei was at first a responsible and caring father figure toward his family but after Raito died and using the Evil Tail, Ryubei grew mad thinking only about his plans of the Gaia Impact regardless of the dangers on the people of Futo including the Dopants (who he sees them as research specimens) and his own family (appearing to be protective of it while he really has no qualms about using his son and youngest daughter). He does not seem to consider the Kamen Riders a threat to his plans, instead using the data off of them as a means to perfect his plans for Wakana before turning his attention to regain Philip and complete his plan to initiate the Gaia Impact. The only living thing that Ryubei appeared to care about at all is his cat Mick. It was later deduced by Shotaro however, that Ryubei still had some of his humanity intact and did care about his family which he tried to hide with the Evil Tail. When he is defeated and the Gaia Impact somewhat fails, he starts to remember who he was and remembered the better times with his family.

Dopant Form

Main article: Terror Dopant

Terror Dopant

―Transformation announcement[src]
  • Height: 185 cm
  • Weight: 97 kg

With the Terror Memory and the prototype Gaia Driver, Ryubei can transform into the Terror Dopant (テラー・ドーパント, Terā Dōpanto), who can increase the fear in his victims to maddening levels. He has also shown to be able to use this outside his Dopant form. He can also summon the Terror Field (テラーフィールド, Terā Fīrudo) to burn his victims or teleport himself and others across long distances.

Although somewhat weakened when using the Terror Dragon, cosmetically noticeable through his headdress which changes from blue to brown, the Terror Dopant was still strong enough to overpower Double's basic form.

Appearances: W Episodes 2, 4, 9, 10, 18, 28, 35-36, 38, 45-46

Terror Dragon

  • Length: 1,360 cm

Terror Dopant can project his power into his headdress to create a Barong-like creature familar known as the Terror Dragon (テラードラゴン, Terā Doragon).

However, this leads the original Dopant more vulnerable to attacks, and if the Terror Dragon is destroyed, the Terror Dopant would have reduced effectiveness.

Appearances: W Episodes 45-46

In other media

Behind the Scenes

Concept Art

Terror Dopant was designed by Katsuya Terada (寺田 克也, Terada Katsuya).


Icon-w.png Kamen Rider W
Narumi Detective Office
Shotaro Hidari - Philip - Akiko Narumi - Sokichi Narumi† - Tokime
Memory Drivers
Doubledriver - Acceldriver - Lostdriver
Gaia Memory-related
Gaia Memories - Memory Gadgets - Fang Memory - Xtreme Memory - Trial Memory - Gaia Memory Enhancing Adapter
Metalshaft - Triggermagnum - Engineblade - Skullmagnum - Prismbicker - Eternaledge - Shroudmagnum
Revolgarry - Hardboilder - Gunner A - Diablossa - Skullboilder - Skullgarry - Hardmammother
The Futo Irregulars
Santachan - Watcherman- Queen & Elizabeth - Isamu Bito
Futo Police Department
Ryu Terui - Mikio Jinno - Shun Makura
Museum and the Dopants
Foundation X
The Sonozaki Family: Terror - Claydoll - Taboo/R Nasca - Nasca - Smilodon - Masquerade Dopants
Dopants: Magma Dopant - T-Rex Dopant - Money Dopant - Anomalocaris Dopant - Cockroach Dopant - Sweets Dopant - Virus Dopant - Violence Dopant - Arms Dopant - Bird Dopant - Ice Age Dopant - Triceratops Dopant - Liar Dopant - Puppeteer Dopant - Invisible Dopant - Nightmare Dopant - Beast Dopant - Zone Dopant - Yesterday Dopant - Quetzalcoatlus Dopant - Gene Dopant - Jewel Dopant - Old Dopant - Utopia Dopant - Energy Dopant
Movie Exclusive Villains: Dummy Dopant - Heat Dopant - Trigger Dopant - Metal Dopant - Luna Dopant - Cyclone Dopant - Bat Dopant - Spider Dopant - Kamen Rider Eternal - Commander Dopant - Eyes Dopant
Novel-Exclusive Villains (The One Who Continues After Z): Zoo Dopant - Zero Dopant - Queen Bee Dopant - Flower Dopant - Elephant Dopant - Dolphin Dopant - Salamander Dopant - Fish Dopant - Bird Dopant - Ape Dopant - Bee Dopants
Manga Exclusive Villains (Futo Tantei): Road Dopant - Aurora Dopant - Meganeura Dopant -Brachiosaurus Dopant - Scream Dopant - Alcohol Dopant - Puzzle Dopant - Reactor Dopant - Antlion Dopant - Owl Dopant - Trash Dopant - Caracal Dopant - Toadstool Dopant
Yukiji Bando - Kazuha - Hideo - Mamoru Nikaido - Sabu
Katsumi Daido - Maria S. Cranberry - Reika Hanehara - Kyosui Izumi - Gozo Domoto - Ken Ashiwara
Fuuto PI Chapters
1 - 2 - 3 - 4 - 5 - 6 - 7 - 8 - 9 - 10 - 11 - 12 - 13 - 14 - 15 - 16 - 17 - 18 - 19 - 20 - 21 - 22 - 23 - 24 - 25 - 26 - 27 - 28 - 29 - 30 - 31 - 32 - 33 - 34 - 35 - 36 - 37 - 38 - 39 - 40 - 41 - 42 - 43 - 44 - 45 - 46