This article is about a/an episode in Kamen Rider Build.
Red alert WARNING: This episode contains scenes of blood and bloodshed. Viewer discretion is advised!

Surging Magma! (ほとばしれマグマ! Hotobashire Maguma!) is the thirty-first episode of Kamen Rider Build. It features the debut of Cross-Z Magma.


Ryuga Banjo may not be human… Everyone froze after hearing Misora's words spoken while fighting Rogue within the Pandora Tower. Rogue was speaking about using human experimentation on Ryuga’s girlfriend, Kasumi. Not only that but Blood Stalk was involved as well. Is Ryuga truly not a human? Meanwhile, the Kamen Riders alongside Sento burst within the Pandora Tower that is being controlled by Stalk. Just when that happens, something strange happens to Ryuga…


to be added


Guest Casts

Suit Actors

Forms and Collectibles Used


  • Bottle used:
    • Build
      • Biotic: FullFull RabbitTank (Rabbit Mode)
      • Abiotic: FullFull RabbitTank (Tank Mode)
      • Other: Hazard Trigger
    • Cross-Z
    • Rogue
      • Biotic: Crocodile Crack
      • Abiotic: N/A
    • Blood Stalk
      • Biotic: Cobra
      • Abiotic: N/A
  • Form used:
    • Build
      • TankTank Form, RabbitRabbit Form
    • Cross-Z
      • Cross-Z, Cross-Z Magma


  • Jelly used:
    • Grease
      • Robot


  • Gear used:
    • Remocon Bro's
      • Gear Remocon
    • Hell Bro's
      • Gear Engine, Gear Remocon


  • to be added


Ryuga Closing Screen
  • Closing Screen Fullbottles
    • Kamen Rider: Cross-Z
    • Fullbottles: 
      • Biotic: Dragon
      • Abiotic: N/A
      • Other: Dragon Magma
  • Count at episode end
    • Bottles in Build's possession:
      • Biotic: Rabbit, Taka, Panda, Kaizoku, Unicorn, Rose, Tora, Kujira, Shika, Kirin, Penguin, Obake, Sai
      • Abiotic: Tank, Gatling, Rocket, Densya, Smapho, Keshigomu, Televi, UFO, Jet, Pyramid, Senpuki, Sukebo, Magnet, Dryer
      • Other: RabbitTank Sparkling, FullFull RabbitTank
    • Bottles in Cross-Z's possession:
    • Bottles in Grease's possession:
      • Biotic: Wolf, Kuma, Kuwagata, Fukurou
      • Abiotic: Robot, Helicopter, Castle
    • Bottles in (Night) Rogue's possession: Bat, Crocodile Crack, Phoenix
    • Bottles in Blood Stalk's possession:
      • Biotic: Cobra, Same, Hachi
      • Abiotic: Bike, Sensuikan, Pyramid
    • Jellies in Grease's possession: Robot
    • Gears in Engine Bro's's possession: Gear Engine
    • Gears in Remocon Bro's's possession: Gear Remocon
    • Bottles in Pandora Box:
      • Biotic: Gorilla, Ninjya, Harinezumi, Lion, Octopus, Turtle, Kabutomushi, Dog, Santa Claus, Spider
      • Abiotic: Diamond, Comic, Syoubousya, Soujiki, Light, Watch, Camera, Mic, Cake, Reizoko

External links


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