The Opening Bell Rings

is the twenty-ninth episode of Kamen Rider Build. It features the debut of the Hard Guardians and the full appearance of Vernage following her brief appearance in Episode 25.
==Synopsis==
Due to the settlement of the representative battle, the war will now end! At least, that's what everyone thought would happen. The war did not end, rather, it has gotten much worse. Blood Stalk, who allied himself with Namba Heavy Industries, is finally starting to set his plans into motion. Stalk, who had stolen 10 of the Fullbottles that were under Touto's possession, inserts them into the Pandora Box. All of a sudden, the Sky Wall begins to move, and a phenomenon beyond belief is about to unfold before their very eyes...!
==Plot==
While Namba (disguised as Mido) conducts an opera, Seito invades Touto once again, and Stalk begins inserting Fullbottles into the Pandora Box Panel. Touto's three Riders arrive to find Touto's forces massacred, and the Guardians significantly stronger than before. Once one of the panels is filled, it joins with the Pandora Box, causing the Sky Wall to shift suddenly. Misora and Taizan scream in horror as they watch a massive circular structure appear in the center.
==Cast==
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===Guest Casts===
*Secretary: 
*Touto Official: , 
===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)
***Abiotic: FullFull RabbitTank (Tank Mode), Rocket (in Fullbottle Buster), Jet (in Fullbottle Buster)
***Other: Hazard Trigger
**Grease
***Biotic: Kuma (in Sclash Driver), Kuwagata (in Twin Breaker), Fukurou (in Twin Breaker)
***Abiotic: Castle (in Sclash Driver), Gatling (in Twin Breaker)
**Blood Stalk
***Biotic: Cobra
***Abiotic: N/A
*Form used:
**Build
***RabbitRabbit Form, TankTank Form
===Sclashjellies===
*Jelly used:
**Cross-Z Charge
***Dragon
**Grease
***Robot
===Gears===
*Gear used:
**Engine Bro's
***Gear Engine
**Remocon Bro's
***Gear Remocon
==Errors==
*The scene where Kazumin exits out the door, Banjo's voice is heard but his mouth does not move.
==Notes==
*As part of Super Hero Time, this episode aired alongside episode 8, .
*Viewership: 2.4%
*Formula of the title:A(3,2)=A(2,A(2,A(2,1)))=29 ()
*Fullbottles Obtained: N/A
*Closing Screen Fullbottles & Sclashjellies:
**Kamen Rider: Build, Cross-Z Charge & Grease
**Fullbottles: FullFull RabbitTank Bottle (Rabbit Mode)
**Sclashjellies:
***Dragon, Robot
*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, Senpuki, Sukebo, Magnet, Dryer
***Other: RabbitTank Sparkling, FullFull RabbitTank
**Bottles in Cross-Z (Charge)'s possession:
***Biotic: Dragon
***Abiotic: Lock
***Other: Cross-Z Dragon
**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 Cross-Z Charge's possession: Dragon
**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
* Kamen Rider Build gets a new opening sequence since this episode.
**At the cafe scene, Kazumi Sawatari stares at a violin, likely a nod to his actor's former role as Otoya Kurenai from Kamen Rider Kiva
*It is the second time since episode 23 to mention a type of currency used in World of Build which is not that of the yen (¥), but something known as a , which 1 dolk highly resembles $1 of the American currency.
==External links==
*TV Asahi's official episode guide for 開幕のベルが鳴る
*Toei TV's official episode guide for 開幕のベルが鳴る
==References==
Category:Episodes with changes to the intro