Surging Magma!

is the thirty-first episode of Kamen Rider Build. It features the debut of Cross-Z Magma.
==Synopsis==
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…
==Plot==
to be added
==Cast==
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===Guest Casts===
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===Suit Actors===
*Kamen Rider Build: 
*Kamen Rider Cross-Z: 
*Kamen Rider Grease: 
*Kamen Rider Rogue: 
*Blood Stalk: 
*Remocon Bro's, Hell Bro's: 
*Press Clone Smash: 
*Stretch Clone Smash: 
==Forms and Collectibles Used==
===Fullbottles===
*Bottle used:
**Build
***Biotic: FullFull RabbitTank (Rabbit Mode)
***Abiotic: FullFull RabbitTank (Tank Mode)
***Other: Hazard Trigger
**Cross-Z
***Biotic: Dragon, Dragon Magma
***Abiotic: N/A
***Other: Cross-Z Dragon, Cross-Z Magma Knuckle
**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
===Sclashjellies===
*Jelly used:
**Grease
***Robot
===Gears===
*Gear used:
**Remocon Bro's
***Gear Remocon
**Hell Bro's
***Gear Engine, Gear Remocon
==Errors==
*to be added
==Notes==
*As part of Super Hero Time, this episode aired alongside episode 10, .
*Viewership: 3.3%
*Formula of the title:M_5=2^5-1=31 ()
*Fullbottles Obtained: N/A
*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:
***Biotic: Dragon, Dragon Magma
***Abiotic: Lock
***Other: Cross-Z Dragon, Cross-Z Magma Knuckle
**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==
*TV Asahi's official episode guide for ほとばしれマグマ！
*Toei TV's official episode guide for ほとばしれマグマ！
==References==
ru:Магма выплеснулась!
Category:New Form Episode