This article is about a/an support robot in Kamen Rider Build.

Cross-Z Dragon

Cross-Z Dragon (Dragon Mode)

Cross-Z Dragon Adapter Mode

Cross-Z Dragon (Adapter Mode)

"Cross-Z Flame!"
―Fullbottle insertion announcement in Dragon Mode[src]

"Wake Up!"
―Cross-Z Dragon adapter activation[src]

"Cross-Z Dragon! Are you ready? Wake up burning! Get Cross-Z Dragon! Yeah!"
―Cross-Z transformation announcement[src]

"Ready, go! Dragonic Finish!"
―Cross-Z finisher announcement[src]

"Ready, go! Let's Finish/Break!"
―Twin Breaker's finisher announcement[src]

The Cross-Z Dragon (クローズドラゴン Kurōzu Doragon) is a small dragon-like flying robotic companion created by Sento Kiryu to assist Ryuga Banjo, complimenting his Dragon Fullbottle. It also functions as a slot adapter for the Build Driver, which Ryuga uses to transform into Kamen Rider Cross-Z and as the slot adapter in the Twin Breaker for Cross-Z Charge to perform a finisher.


Created by Sento Kiryu, the Cross-Z Dragon was introduced to Ryuga as they pursued Faust's base beneath the Nebula Gas at the Sky Wall. Eluding the Guardians, the Cross-Z Dragon sucked out the poison from Ryuga inflicted by Blood Stalk. Moonsault of Anger

Accompanying Sento and Ryuga to Hokuto, the Cross-Z Dragon aided Ryuga in covering Sento when he was beaten by Blood Stalk. Recovering the Gatling Fullbottle, the Cross-Z Dragon channeled its power to assault Blood Stalk. Though singed in the crossfire, Ryuga was nonetheless able to take the Rocket Fullbottle from Blood Stalk's Transteam Gun and give it to Build, allowing him to turn the tide. The Devil's Scientist

When most of the Fullbottles were taken by Night Rogue, leaving only the Lock and Dragon Fullbottles, Sento thought of a way for Ryuga to transform by synchronizing with the Cross-Z Dragon, since Ryuga's Hazard Level had just reached a level of 3, while Build's KeyDragon form was too unstable for Sento to use. Ryuga was eventually able to use the Cross-Z Dragon with the Dragon Fullbottle to transform into Cross-Z for the first time, with the immense power of the Dragon Fullbottle enabling him to defeat the Stretch Smash in just one hit. Burning Dragon

Temporarily overriding Ryuga's free will, "Kengo Ino" of the Blood Tribe took the Great Cross-Z Dragon and his Build Driver. By inserting the Cobra Lost Fullbottle into the Great Cross-Z Dragon as well as employing the Hazard Trigger that he had Ryuga steal from Sento, "Kengo" assumed the form of Kamen Rider Blood. Ultimately, however, the Great Cross-Z Dragon was returned to Ryuga when he and Sento defeated Blood as Kamen Rider Cross-ZBuild. Kamen Rider Build: Be The One


The Cross-Z Dragon is composed of the following parts:

  • The Blaze Chucker (ブレイズチャッカー Bureizu Chakkā) is a flame emitting device incorporated in the head of the Cross-Z Dragon. When spraying fire, its temperature and attack range can be fine-tuned, allowing it to grill the target at will.
  • The Capri Fang (カプリファング Kapuri Fangu) is the Cross-Z Dragon's fang. Although it is small, the tip is very sharp and can be used for attack. In addition, it has a detoxification function, and imbibing/decomposing poison by biting a person to be cured.
  • The CZ Dragon Head (CZドラゴンヘッド CZ Doragon Heddo) is the Cross-Z Dragon's head. The growth type AI unit Trust Bringer (トラストビリンガー Torasuto Biringā) is built inside. Also, monitors the state of Ryuga Banjo's body and mind, and if it meets the condition, unlocks the transformation function etc. loaded.
  • The Volcanic Charger (ボルケニックチャージャー Borukenikku Chājā) is a special reaction blast furnace mounted on the Cross-Z Dragon. In addition to generating the operating energy of the Cross-Z Dragon, it is possible to heat the captured Transgel Solid at an extremely high temperature and double its component amount. Also, by using the ingredients of the bottle, it can increase the power of the flame exhaled through the mouth, via the Cross-Z Flame attack.
  • The Fullbottle Slot (フルボトルスロット Furu Botoru Surotto) is a slot for the insertion of a Fullbottle. It has the role of activating the Transgel Solid (トランスゲルソリッド Toransugeru Soriddo) in the loaded bottle with a special pulse.
  • The Heat Gale Wing (ヒートゲイルウィング Hīto Geiru Wingu) is the Cross-Z Dragon's exothermic flight unit. It is possible to flight and float freely by controlling the air flow with flapping flames that generate hot air.
  • The Tornado Tail (トーネードテイル Tōnēdo Teiru) is the Cross-Z Dragon's tail. It has a role as a posture control device, and stable flight can be achieved by swinging up and down and right and left.
  • The Eruption Leg (イラプションレッグ Irapushon Reggu) is the Cross-Z Dragon's legs. Because it incorporates a small power cylinder, it can carry any object 50kg or less on its back. It is excellent in heat resistance and it is possible to walk loose on lava.

Powers and Abilities

  • Music: The Cross-Z Dragon will randomly play one of two short music tunes for no particular purpose, whether convenient for sneaking around or not. This can be seen as a possible way of it to either communicate or distract an opponent.
  • Dragon Fire Breath: The Cross-Z Dragon is capable of breathing fire, similar to Dragreder's Drag Breath.
  • Poison Absorption: The Cross-Z Dragon can extract liquid poisons from the infected person's body by biting their necks.
  • Fullbottle Augmentation: Like its creator and partner, the Cross-Z Dragon is capable of utilizing new abilities based on what Fullbottle is plugged into its slot through its Cross-Z Flame (クロズフレーム Kurozu Furēmu) attack.
    • Organic:
      • Dragon: The Cross-Z Dragon can fire blasts of blue energy that give off shockwaves on impact.
    • Inorganic:
      • Gatling: The Cross-Z Dragon can consecutively shoot blue fire bullets from its mouth.



The user inserts the Dragon Fullbottle into the Fullbottle Slot on the Cross-Z Dragon, folds the CZ Dragon Head and Tornado Tail, and inserts the Cross-Z Dragon into the Build Driver. After cranking the Vortex Lever, the Driver then initializes the Snap Ride Builder (スナップライドビルダー Sunappu Raido Birudā) after the essences have hardened into the Halfbodies, snapping the two parts together and completing the transformation. The Snap Ride Builder will not appear if the user is moving during the transformation, while in some instances, the pneumatic tubes of the Snap Rider Builder will simply appear in a quick flash so as to speed up the transformation.[1]


Build Driver

After cranking the Vortex Lever, Cross-Z performs the Dragonic Finish (ドラゴニックフィニッシュ Doragonikku Finisshu): This attack has two variations:

  • Rider Kick: Cross-Z summons a blue and orange energy chinese dragon that flies behind him, then jumps up as the dragon breaths fire, sending him at the enemy, then delivers a roundhouse kick whilst his foot is covered in blue energy.
  • Rider Punch: Cross-Z coats his right hand in energy in the shape of a blue chinese dragon head, then delivers a punch.

Twin Breaker

By plugging the Cross-Z Dragon in the Twin Breaker, Cross-Z Charge can perform different finishing attacks depending on what mode it's in.

  • Beam Mode:
    • Let's Finish (レッツフィニッシュ Rettsu Finisshu):
  • Attack Mode:
    • Let's Break (レッツレイク Rettsu Burēku): Cross-Z Charge summons a blue and orange energy Chinese dragon that flies behind him, and use it to stab the enemy.

Beat Closer + Twin Breaker

Cross-Z Charge can combine the powers of the Beat Closer and the Twin Breaker to perform a powerful finisher.

  • Mega Slash/Let's Break (スクラップブレイク/レッツレイク Sukurappu Burēku/Rettsu Burēku): Cross-Z Charge channels the energy of the Cross-Z Dragon in the Twin Breaker in Attack Mode, and the energy of a Fullbottle in his Beat Closer, pulls the handle three times and performs a powerful slash.
    • Lock: The Beat Closer projects an energy version of the Bind Master Key before Cross-Z Charge slashes with it, creating a ball of golden energy before summoning a blue and orange energy chinese dragon that grabs the ball via its mouth, then flies at the enemy with an empowered attack.

Sclash Driver + Twin Breaker

Cross-Z Charge can combine the Twin Breaker’s finisher with the Sclash Driver to perform a powerful finisher.

  • Scrap Break/Let's Break (スクラップブレイク/レッツブレイク Sukurappu Burēku/Rettsu Burēku): Cross-Z Charge summons a blue and orange energy chinese dragon that flies behind him, and use it to stab the enemy before delivering a powerful punch.

Great Cross-Z Dragon

Great Cross-Z Dragon normal mode

Great Cross-Z Dragon (Dragon Mode)

Great Cross-Z Dragon Adapter Mode

Great Cross-Z Dragon (Adapter Mode w/ Cobra Lost Fullbottle)

―Great Cross-Z Dragon adapter activation[src]

"Great Cross-Z Dragon! Are you ready? Wake up Cross-Z! Get Great Dragon! Yeah!"
―Great Cross-Z transformation announcement[src]

"Great Cross-Z Dragon! Are you ready? Wake up Cross-Z! Get Great Dragon! Buraburaburabura Bura~h!!"
―Blood transformation announcement without Hazard Trigger[src]

"Great Cross-Z Dragon! Build Up! Are you ready? Overflow! Wake up Cross-Z! Get Great Dragon! Yeah! Yabei!"
―Great Cross-Z transformation announcement with Hazard Trigger[src]

"Great Cross-Z Dragon! Build Up! Are you ready? Overflow! Wake up Cross-Z! Get Great Dragon! Buraburaburabura Bura~h! Yabei!"
―Blood transformation announcement[src]

"Ready, go! Great Dragonic Finish!"
―Great Cross-Z finisher announcement[src]

"Ready, go! Hazard Finish! Great Dragonic Finish!"
―Blood finisher announcement with Hazard Trigger[src]

"Ready, go! Let's Finish/Break!"
―Twin Breaker's finisher announcement[src]

The Great Cross-Z Dragon (グレートクローズドラゴン Gurēto Kurōzu Doragon) is an upgraded version of the Cross-Z Dragon created when Ryuga Banjo inserts the Great Dragon Evolbottle, which was transformed from the Dragon Evolbottle when Banjo generated new Evolto DNA. Banjo uses it with the Great Dragon Evolbottle to transform into Kamen Rider Great Cross-Z, and Kengo Ino uses it with the Cobra Lost Fullbottle and Hazard Trigger to transform into Kamen Rider Blood.

The design of the Great Cross-Z Dragon has the same components as its original incarnation, save for a palette swap similar to the Evol-Driver's color scheme. Its functions and transformation sequence are also identical to the original Cross-Z Dragon.


After cranking the Vortex Lever of the Build Driver, Great Cross-Z can perform the Great Dragonic Finish (グレートドラゴニックフィニッシュ Gurēto Doragonikku Finisshu), which has two variations:

  • Great Cross-Z performs a flying kick covered in crimson and blue energy.
  • Great Cross-Z performs a roundhouse kick covered in crimson and blue energy that can strike multiple enemies.

Behind the Scenes


The Cross-Z Dragon is voiced by KORBY, who also voices the Build Driver.

The Great Cross-Z Dragon is voiced by Norio Wakamoto (若本 規夫 Wakamoto Norio), who also voiced the Sclash Driver, Twin Breaker, and Cross-Z Magma Knuckle.


  • Unlike many other dragons in past series, the size of the Cross-Z Dragon is similar to Tatsulot's, with its physical appearance similar to Castle Doran.
    • Coincidentally, the announcement when transforming to its adapter mode is similar to Kamen Rider Kiva's first finisher (Darkness Moon Break).
  • Given the ability to breathe fire, and the physics lab theme for Build’s arsenal, the Cross-Z Dragon is likely themed after a bunsen burner, heating up the chemical to cause a reaction, rather than by pairing it with another chemical stored in a fullbottle.
  • This is the first device designed as an adapter to access a Rider's Main Form.
    • This is the first instance where an intermediary is still utilized in the same manner as the series' collectible with the Driver to access the Main Form.
      • The last time this occurred was with Kamen Rider Double's use of the Xtreme Memory, but to access his Final Form.
        • Oddly, Cross-Z's final form would be attained through another adapter, but an inverse in concept: a mechanical-based device with both transformation and finishers including serpentine constructs, instead of a device designed after an animal and the finishers and transformation being more mechanical.
  • Similar to how the Evol-Driver announces the majority of Fullbottles by the opposite language as the Build Driver, the Great Cross-Z Dragon's adapter activation announcement can be roughly translated to "Awakening", which is similar to the normals Cross-Z Dragon's adapter activation announcement.
  • The Cross-Z Dragon's transformation into Great Cross-Z Dragon through the Great Dragon Evolbottle is reminiscent to Kamen Riders Ryuki and Knight activating their Survive Forms, upon taking out their Survive (Rekka and Shippu, respectively) Advent Cards, their respective Visors transform into their upgraded forms.



  1. Production-wise, this is likely to save on the CGI budget.

External links