The Truth of the Pandora Box

is the thirtieth episode of Kamen Rider Build. It features the debut of the Cross-Z Magma Knuckle and the Dragon Magma Fullbottle.
==Synopsis==
Misora was possessed once again by the spirit of Vernage, the Queen of Mars, as she quickly evacuates all the Riders from the battlefield! Just then, she says something that shocks everyone. “You will be hope…” Sento fights against Stalk to try and reclaim the Pandora Box as they storm the Pandora Tower, and meanwhile, a secret about Banjo is revealed that confirms Vernage’s words…
==Plot==
to be added
==Cast==
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===Guest Casts===
*TV Announcer: 
===Suit Actors===
*Kamen Rider Build: 
*Kamen Rider Cross-Z (Charge): 
*Kamen Rider Grease: 
*Blood Stalk: 
*Engine Bro's: 
*Remocon Bro's: 
==Forms and Collectibles Used==
===Fullbottles===
*Bottle used:
**Build
***Biotic: FullFull RabbitTank (Rabbit Mode), Rabbit
***Abiotic: Tank, FullFull RabbitTank (Tank Mode)
***Other: Hazard Trigger
**Cross-Z
***Biotic: Dragon, Dragon Magma, Taka (in Cross-Z Magma Knuckle)
***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
***RabbitRabbit Form, RabbitTank Form, TankTank Form
**Cross-Z
***Cross-Z
===Sclashjellies===
*Jelly used:
**Cross-Z Charge
***Dragon
**Grease
***Robot
===Gears===
*Gear used:
**Engine Bro's
***Gear Engine
**Remocon Bro's
***Gear Remocon
==Errors==
*When Cross-Z presses the Dragonic Igniter button on the Cross-Z Magma Knuckle after inserting the Taka Fullbottle, the Fullbottle briefly bounces out of the slot a little, likely due to the Fullbottle prop not fitted properly into the slot.
==Notes==
*As part of Super Hero Time, this episode aired alongside episode 9, .
*Viewership: 2.7%
*Formula of the title: \arg_{n}\max[\{totative \text{ of} \text{ n}\}\subset\{prime\}]=30 ()
*Fullbottles Obtained: Dragon Magma
*Closing Screen Fullbottles
**Kamen Rider: Cross-Z and Blood Stalk
**Fullbottles: 
***Biotic: Dragon, Cobra
*Count at episode end
**Bottles in Build's possession:
***Biotic: Rabbit, 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, Taka, 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
*This is the last time Build uses the RabbitTank Form until the last episode
*It features the return of the regular Cross-Z form after its last appearance in episode 17 due to the destruction of Ryuga's Sclash Driver and the Dragon Sclashjelly.
==External links==
*TV Asahi's official episode guide for パンドラボックスの真実
*Toei TV's official episode guide for パンドラボックスの真実
==References==