An Oath to Be The One

is the forty-sixth episode of Kamen Rider Build. It features Kazumi's first transformation into Grease Blizzard Form. It also features the first appearance of the white Last Pandora Panel.
==Synopsis==
Suddenly Evolto, who was impersonating Seito's Prime Minister Mido, reveals himself to the world and his intentions to destroy it! This marks the beginning of the final battle of Evolto vs. humanity. All of the Kamen Riders including Sento are determined to fight until the end. Their key to victory lies in the White Pandora Panel originating from the data that Shinobu left behind. Evolto's planetary destruction has begun. The fight for the last Lost Fullbottle is on the line. The Kamen Riders set their aim at the summit of the Pandora Tower, and Evolto himself!
==Plot==
to be added
==Cast==
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===Guest Casts===
*TV Reporters: , , 
===Suit Actors===
*Kamen Rider Build: 
*Kamen Rider Cross-Z: 
*Kamen Rider Grease: 
*Kamen Rider Rogue: 
*Kamen Rider Evol: 
==Forms and Collectibles Used==
=== Fullbottles ===
*Bottle used:
**Build
***Biotic: N/A
***Abiotic: N/A
***Other: Genius
**Cross-Z
***Biotic: Dragon Magma
***Abiotic: N/A
***Other: Cross-Z Magma Knuckle
**Grease
***Biotic: N/A
***Abiotic: N/A
***Other: North Blizzard, Grease Blizzard Knuckle
**Rogue
***Biotic: Crocodile Crack
***Abiotic: N/A
*Form(s) used:
**Build
***Genius Form
**Cross-Z
***Cross-Z Magma
**Grease
***Grease Blizzard
===Sclashjellies===
*Jelly used:
**Grease
***Robot
===Evolbottles===
*Bottle used:
**Evol
***Biotic: Cobra
***Abiotic: Rider
***Other: Evol Trigger
*Form used:
**Evol
***Black Hole Form (Phase 4: Perfection), Cobra Form (Phase 1)
==Errors==
*Kazumi does not pull the handle over the Grease Blizzard Knuckle before inserting it into the Build Driver. This error is carried over to the next episode as well.
==Notes==
*As part of Super Hero Time, this episode aired alongside episode 25, .
*Viewership: 2.8%
*Formula of the title:\sqrt[3]{3^3+36^3+37^3} =46 ()
*Closing Screen Fullbottle:
**Kamen Rider: Grease Blizzard
**Fullbottle: North Blizzard
*Count at episode end
**Bottles in Build's possession:
***Biotic: Gold Rabbit
***Abiotic: N/A
***Other: RabbitTank Sparkling, FullFull RabbitTank, Genius
**Bottles in Cross-Z's possession:
***Biotic: Silver Dragon, Dragon Magma
***Abiotic: N/A
***Other: Cross-Z Dragon, Cross-Z Magma Knuckle
**Bottles in Grease's possession:
***Biotic: N/A
***Abiotic: Castle
***Other: North Blizzard
**Bottles in Rogue's possession: Crocodile Crack
**Bottles in Evol's possession:
***Biotic: Gorilla, Taka, Ninjya, Panda, Harinezumi, Lion, Kaizoku, Octopus, Phoenix, Wolf, Unicorn, Rose, Turtle, Kabutomushi, Kuma, Dog, Santa Claus, Spider, Tora, Kujira, Shika, Kirin, Penguin, Obake, Same, Hachi, Sai
***Abiotic: Tank, Diamond, Gatling, Comic, Rocket, Syoubousya, Soujiki, Lock, Densya Light, Robot, Smapho, Keshigomu, Helicopter, Watch, Camera, Televi, Mic, Cake, Reizoko, UFO, Jet, Pyramid, Senpuki, Sukebo, Magnet, Bike, Sensuikan, Dryer, Hammer
**Bottles in MadRogue's possession:
***Biotic: Bat
***Abiotic: Engine
**Jellies in Grease's possession: Robot, Dragon
**Evolbottles in Evol's possession:
***Biotic: Cobra, Rabbit
***Abiotic: Rider
**Evolbottles in Cross-Z's possession:
***Biotic: Great Dragon
***Other: Great Cross-Z Dragon
**Lost Bottles in Evol's possession:
***Biotic: Bat, Cobra, Shimauma, Fukurou, Kuwagata
***Abiotic: Hasami, Spanner, CD
*The concept of parallel worlds from Kamen Rider Heisei Generations Final: Build & Ex-Aid with Legend Riders is revisited in this episode. However a crucial difference is highlighted in that while Kaisei Mogami's Enigma destroys worlds, the simultaneous use of both the black and white Box's panels fully merges them into an entirely new one instead.
**The scene in which the characters imagine the two worlds colliding is taken directly from the film.
*Cross-ZBuild Form is first shown during the commercial break of this episode's airing, ahead of the film's release.
*It features the return of the Hokuto Sanbagarasu as imitations made by Evolto.
==External links==
*TV Asahi's official episode guide for 誓いのビー・ザ・ワン
*Toei TV's official episode guide for 誓いのビー・ザ・ワン
==References==
Category:New Form Episode