This article is about a/an weapon/transformation device in Kamen Rider Build.

"(Fullbottle Name)! Mist Match! (Fullbottle name)! (Fullbottle name)! Fire!"
―Transformation announcement[src]

"Steam Break! (Transformation Fullbottle name)!"
―Finisher announcement with Faust Fullbottle[src]

"Fullbottle! Steam Attack!"
―Finisher announcement with any other Fullbottle[src]

"Rifle Mode!"
―Combination with Steam Blade announcement[src]

"(Fullbottle name)! Steam Shot! (Fullbottle name)!"
―Steam Rifle finisher announcement with Faust Fullbottle[src]

"Fullbottle! Steam Attack!"
―Steam Rifle finisher announcement with any other Fullbottle[src]

The Transformation Smoke Pistol Transteam Gun (変身煙銃 トランスチームガン Henshin Enjū Toransuchīmu Gan) is the personal weapon and transformation device of Night Rogue and Blood Stalk. It is also the personal weapon of Kamen Rider Evol. It combines with the Steam Blade to form the Steam Rifle (スチームライフル Suchīmu Raifuru).

It is a simplified version of Kaisei Mogami's Nebulasteam Gun created by Takumi Katsuragi, who worked as Kaisei's assistant. It operates solely on Nebula Gas, rather than the original's combination of Nebula Gas and Bugster Virus[1].

Unlike the Rider System, the Transteam System (トランスチームシステム Toransuchīmu Shisutemu) does not rely upon the user's Hazard Level. This enables people that have not undergone extensive Nebula Gas experimentation to use it. As a result, however, it cannot raise the user's Hazard Level, meaning that the power of the transformation is fixed. Who Takes Off The Veil? ROGUE Hence, Transteam System users must rely solely on their own skill, abilities, and experience in fights.

The schematics for the Transteam Gun and its abilities are detailed in the 2nd file of Project Build.


The Transteam Gun is composed of the following parts:

  • Fullbottle Slot (フルボトルスロット Furubotoru Surotto) - The slot of the Transteam Gun, it takes in a Lost Bottle (Cobra or Bat) used for transformation or a Fullbottle for an attack (i.e. Rocket). It has a function which activates the Transgel Solid inside of the Fullbottle via a special pulse, allowing the Transteam Gun to suck up the Fullbottle's essence.
  • Blazing Steamer (ブレイジングスチーマー Bureijingu Suchīmā) - The gun port of the Transteam Gun, it can shoot out bullets wrapped in hot steam called Steam Burettes (スチームビュレット Suchīmu Byuretto) (On a side note, a Burette is a lab equipment used in chemistry to measure the volume of a liquid or gas. It consists of a glass tube with a stopcock at one end). Additionally, it also shoots out Transgel Steam (トランジェルスチーム Toranjeru Suchīmu), which is used for transformation.
  • Mystic Charger (ミスティックチャージャー Misutikku Chājā) - The silver panel on the Transteam Gun with pipes on it. It is a steam generation unit which is directly mounted onto the gun. It heats up the Lost/Fullbottle's Transgel Solid (essence) and turns it into Transgel Steam, allowing transformation. In addition, Nebula Gas is stored inside of its inner tank, allowing Night Rogue and Blood Stark to change humans into Smash whenever they desire without using laboratory equipment.
  • Power Hit Grip (パワーヒットグリップ Pawā Hitto Gurippu) - The hilt of the Transteam Gun. Because it is composed of materials that can withstand impacts, it can be used as an impromptu striking weapon. Additionally, a computer unit inside it uses combat data to figure out the user's combat style and adjusts shooting behaviour accordingly.



Fullbottles are loaded into the Transteam Gun to transform. Night Rogue uses the Bat Fullbottle to transform, and Blood Stalk uses the Cobra Fullbottle. The transformation command is "Jouketsu" (蒸血 lit. Blood Steam). According to Gentoku Himuro, to use the Transteam Gun, the user needs to have Hazard Level at a suitable level, albeit not as high as the Build Driver's requirement. Night Rogue Chapter

Users (chronological order)

User Transformation Episode Obtained Description
Gentoku Himuro
Night Rogue
Prologue: NIGHT ROGUE RISES The first Transteam Gun. Was created by Faust scientists along with Bat Fullbottle, placed in a glass case. When Gentoku announced the founding of Faust, he smashed the case and took the Transteam Gun and Fullbottle to transform, christening himself Night Rogue.

He continued using it for 3 years, but lost it when it was presumably taken by Namba Heavy Industries Ltd. after his exile from Touto and given to Utsumi.

Evolto/Soichi Isurugi
Blood Stalk/Kamen Rider Evol
Pre-series The second Transteam Gun. Evolto had already been in possession of one for an unknown period of time by the start of the series.
Nariaki Utsumi
Night Rogue/Kamen Rider MadRogue
Theory of Conspiracy (briefly)
Kamen Rider Build: Raising the Hazard Level ~7 Best Matches~: First Chapter
Utsumi originally transformed into Night Rogue to act as Gentoku's decoy in order to keep his identity a secret, with the Transteam Gun being returned to its owner afterword.

Later, he would take Gentoku's Transteam Gun and transform into Night Rogue several more times in order to collect data on Sento.


The Transtream Gun has 2 finishers: the Steam Break (スチームブレイク Suchīmu Bureiku) with the Bat Fullbottle or Cobra Fullbottle/Evolbottle and the Steam Attack (スチームアタック Suchīmu Atakku) with any other Fullbottle.

When combined with the Steam Blade to form the Steam Rifle, its finishers are the Steam Shot (スチームショット Suchīmu Shotto) with the Bat Fullbottle or Cobra Fullbottle/Evolbottle and the Steam Attack with any other Fullbottle.

  • Cobra: Blood Stalk shoots a purple cobra energy blast that detonates upon impact.

  • Rocket: Blood Stalk shoots a powerful blast attack that takes the form of a rocket. The rocket flies around the enemy before coming to the ground for an explosion.

  • Rabbit Evolbottle: Evol runs extremely fast in a circle around the enemy and fires at them with the Steam Rifle.

  • Bat: Night Rogue shoots a steam bullet at the enemy.
  • Cobra: Blood Stalk shoots a purple cobra energy blast that detonates upon impact.

  • Cobra
    • Elek Steam: Evol shoots a red and blue homing shot coated in electricity


  • Being a transformation device that also doubles as a gun, it is similar to the Drake Glip, DiendriverBreak Gunner and Lupin Gunner.
    • Particular aspects make it closer to the Break Gunner, as it was designed to transform into a Rider-like form as opposed to the other aforementioned devices, and could use the collectible devices used by protagonists and antagonists of the series.
  • Interestingly, Transteam Gun has both small and big models used in the series (as Soichi used the small one to transform and the big one once completing the transformation into Blood Stalk). The small model is likely the size of the toy version.
  • The transformation call, Mist Match, could be a pun on the words mist and mismatch.
  • This is the first transformation device to be used by the series antagonists, capable of combining with a sidearm for more powerful attacks, and make use of the series collectible to augment its power.
    • The closest comparison can be seen in Kamen Rider Chalice (being a series antagonist only by nature), when the Chalice Rouzer (the Rider's personal weapon) was inserted into the Chalice Arrow (the main weapon for the template of said Rider).



  1. Uchusen (宇宙船 Uchūsen) 159, page 39
Sento Kiryu (Takumi Katsuragi) - Ryuga Banjo - Kazumi Sawatari - Gentoku Himuro - Evolto - Nariaki Utsumi - Shinobu Katsuragi
Movie-exclusive: Kengo Ino - Killbus - Keiji Uraga
Transformation Gear
Fullbottles - Build Driver - Transteam Gun - (Great) Cross-Z Dragon - Sclashjellies - Sclash Driver - Hazard Trigger - Nebulasteam Gun - Cross-Z Magma Knuckle - Evol-Driver - Evol-Trigger - Grease Blizzard Knuckle - Killbuspider - Grease Perfect Kingdom
Drill Crusher - Hawk Gatlinger - 4Koma Ninpoutou - Kaizoku Hassyar - Fullbottle Buster - Steam Blade - Beat Closer - Twin Breaker - Muscle Glove - Solstall Wings - Giant Scratcher - Space Ride Arm - Spine Knuckle - Long Range Cleaner - Trash Converter - Gold Lio Gauntlet - Multi Deluge Gun
Pandora Box - Halfbodies - Fullbottle Holder - Build Phone
Vortex Finish - Hazard Level - Project Build - Sky Wall - Nebula Gas
nascita: Misora Isurugi - Soichi Isurugi - Sawa Takigawa - Kazumi Sawatari - Gentoku Himuro
Kamen Riders: Eiji Hino - Gentaro Kisaragi - Kouta Kazuraba - Takeru Tenkuji - Emu Hojo - Hiiro Kagami - Taiga Hanaya - Kiriya Kujo - Kuroto Dan - Parado - Sougo Tokiwa - Geiz Myokoin - Tsukuyomi
Prime Ministers: Taizan Himuro (Touto) - Yoshiko Tajimi (Hokuto) - Masakuni Mido (Seito)
Namba Heavy Industries Ltd.: Juzaburo Namba - Nariaki Utsumi - Haruhiko Wanibuchi - Guardian
Hell Bro's: Fu Washio - Rai Washio - Yoshikazu Takahashi - Norio Matsui
Aliens: Vernage
Gentoku Himuro - Evolto - Nariaki Utsumi - Takumi Katsuragi - Shingo Kuwata - Eita Kawai - Yoshikazu Takahashi - Norio Matsui
Touto: Needle Smash - Strong Smash - Burn Smash - Flying Smash - Mirage Smash - Square Smash - Press Smash - Ice Smash - Stretch Smash
Hokuto: Castle Hard Smash - Stag Hard Smash - Owl Hard Smash
Kaiser: Kaisei Mogami (World of Ex-Aid)
Kengo Ino - Ryoka Saiga - Mitsuomi Gobara - Evolto - Killbus
Keiji Uraga - Simon Marcus (Phantom Crusher)
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