|This article is about a/an rider in Kamen Rider Decade.|
Shinji Tatsumi is a young man who worked for the Atashi Journal as its photographer alongside its top writer Ren Haguro until he left the Journal three years ago without explaining himself. Since then Shinji was distraught and felt betrayed as a result. However, when his editor Reiko Momoi is mysteriously murdered, Shinji finds Ren present at the scene. Soon after, Shinji is chosen to become Kamen Rider Ryuki, though is reluctant to join the Kamen Rider Trial that would judge the fate of the suspected murderer: Natsumi Hikari.
As the trial begins, Shinji crosses paths with Yusuke Onodera and Tsukasa Kadoya, who represents Natsumi as her defense attorney. After telling them what the official sources say behind Reiko's death and admitting he feels that Natsumi's innocent, Shinji accompanies Tsukasa and Yuusuke to the crime scene to meet Kamata who confirms Ren's appearance at the Journal around Reiko's death. While Kamata and Tsukasa enter the Mirror World to fight, Shinji confronts Ren to demand what he was doing at the Atashi Journal. Once in the Mirror World, Shinji challenges Ren as he believes that Ren is the true murderer and has framed Natsumi. However, their fight is interrupted once Decade appears and challenges Knight with Ryuki watching their fight with contempt for Knight. Shinji later uses the Time Vent card Ren had acquired to reverse the flow of time, saving Reiko Momoi from murder, discovering the reason why Ren left the group 3 years ago, and exposing Kamata as the murderer. Along with Decade, Shinji fights Abyss, revealing that Kamata is actually the Paradoxa Undead.
He later appears in Kamen Rider × Kamen Rider W & Decade: Movie War 2010 alongside the other Riders of the Nine Worlds to help in reviving Tsukasa and helps him battle Super Shocker, assuming Ryuki Survive with the help of Decade's K-Touch and later into his Ryuki Dragredder form with the All Rider Final Form Ride Card to fight the Super Crisis Fortress.
Tatsumi as Ryuki, alongside Blade attacked Tsukasa in a warehouse. They throw him out and continue attacking, forcing him to transform and face them. Tsukasa transforms into Decade Violent Emotion and destroys Ryuki using the Blade Final Form Ride Blade Blade, immediatelly afterwards destroying Blade and collecting the Kamen Ride cards that fell after their disappearance. This Ryuki isn't shown in the movie again, although he's presumably restored alongside the other Riders afterwards.
Movie War 2010 currently remains the last appearance of Shinji Tatsumi. The Ryuki that appears in OOO, Den-O, All Riders: Let's Go Kamen Riders and Kamen Rider × Super Sentai: Super Hero Taisen is the original Ryuki, Shinji Kido.
- Punching Power: 10 t (200 AP)
- Kicking Power: 20 t (400 AP)
- Maximum Jump Height: 35 m
- Maximum Running Speed: 100 m per 5 seconds
- Sight and Hearing: 15 km 
Tatsumi can transform into Kamen Rider Ryuki using his Advent Deck and V-Buckle upon forming a contract with Dragreder. He is equipped with the Drag Visor on his left arm. In comparison to the other Riders, his parameters are balanced.
Through the use of his Sword Vent Advent Card, Ryuki can arm himself with the Drag Saber (ドラグセイバー Doragu Seibā), a sword derived from Dragreder's tail. His Strike Vent arms him with the Drag Claw (ドラグクロー Doragu Kurō), a gauntlet capable of shooting fireballs that is derived from Dragreder's head. With the Drag Claw, Ryuki can perform the Drag Claw Fire (ドラグクローファイヤー Doragu Kurō Faiyā) attack with Dragreder, in which he and Dragreder each launch a fireball at the opponent. His Guard Vent equips him with the Drag Shield (ドラグシールド Doragu Shīrudo), two shields derived from segments of Dragreder's body that can be held by hand or mounted on Ryuki's shoulders.
By using his Final Vent, Ryuki can execute his finisher, the Dragon Rider Kick (ドラゴンライダーキック Doragon Raidā Kikku), in which he jumps into the air with Dragreder flying behind him. Dragreder then breathes fire at Ryuki, propelling him into a flying kick that strikes the enemy.
- ―Transformation announcement[src]
- Punching Power: 15 t (300 AP)
- Kicking Power: 25 t (500 AP)
- Maximum Jump Height: 45 m
- Maximum Running Speed: 100 m per 4.5 seconds
- Sight and Hearing: 20 km
Kamen Rider Ryuki Survive (仮面ライダー龍騎サバイブ Kamen Raidā Ryūki Sabaibu) is Ryuki's final form, assumed using the Survive Rekka Advent Card, though Tatsumi only achieved it with the aid of the K-Touch. The Survive Rekka card transforms the Drag Visor into the the Drag Visor-Zwei. Transforming into Survive form also causes Dragreder to transform into Dragranzer. Survive Form enhances all of Ryuki's stats, allowing him to surpass all other Riders, with the exception of those who are also using a Survive Advent Card, such as Knight Survive and Odin.
Using the Sword Vent Advent Card converts the Drag Visor-Zwei to a blade mode named the Drag Blade (ドラグブレード Doragu Burēdo).The Drag Visor-Zwei can also function as a ranged weapon by shooting fireballs. By using the Shoot Vent, Ryuki can perform the Meteor Bullet (メテオバレット Meteo Buretto) attack alongside Dragranzer, in which he and Dragranzer each launch a fireball at the opponent.
By using his Final Vent, Ryuki Survive can perform his final attack, the Dragon Fire Storm (ドラゴンファイヤーストーム Doragon Faiyā Sutōmu), which transforms Dragranzer into a bike for Ryuki to ride. Ryuki drives toward the enemy and performs a wheelie, followed by Dragranzer shooting several opponents at the opponent from its mouth. Finally, Ryuki slams into the opponent, destroying it.
- "Final Form Ride: R-R-Ryuki!"
- ―Transformation announcement[src]
Kamen Rider Decade's Final Form Ride allows Ryuki to change into Ryuki Dragreder (リュウキドラグレッダー Ryūki Doragureddā). This automatically equips Ryuki with Guard Vent and Sword Vent. While the first transformation required Decade's assistance, Ryuki eventually was able to transform at will into this form. Ryuki can also shoot fireballs from his mouth in this form.
- Advent Deck - Transformation device and Advent Card holder
- V-Buckle - Transformation belt
- Advent Cards - Trinkets that enable a Rider to summon Contract Monsters, access equipment, and use special abilities
- Drag Visor - Ryuki's Visor that enables him to use Advent Cards
- Drag Visor-Zwei - Upgraded version of the Drag Visor used by Ryuki Survive
Behind the scenes
- "Tatsu" is the Kun'yomi method of how to pronounce Dragon (竜 ryū).
- His Final Form Ride transformation bears a striking resemblance to RyuuRanger's personal mecha: Mythical Chi Beast RyuseiOh.
- The difference between Kido's view on Akiyama and Tatsumi's view on Haguro is that Kido is very kind towards Akiyama. While Tatsumi on the other hand, became extremely cold on Haguro, even supspecting him as the killer of Reiko.
- Shinji Kido & Koichi Sakakibara - The original users of Kamen Rider Ryuki powers in Kamen Rider Ryuki.
- Adam & Kit Taylor - The riders who donned the powers of Kamen Rider Ryuki in Kamen Rider Dragon Knight.
<ref>tags exist, but no
<references/>tag was found