World of Build

The World of Build (ビルドの世界) is an A.R. World home to Evolto of the Blood Tribe, a malicious alien entity who used the Pandora Box created on his world to destroy numerous planets across the universe, with his penultimate slaughter destroying a civilization which flourished on Mars. As a result of Evolto's subsequent attempt to destroy the Earth, Japan was divided into three regions by the Sky Wall, while his work to regain the power he lost ultimately resulted in the creation of the eponymous Kamen Rider Build.

Sky Wall Disaster
In the year 2007, the Sky Wall Disaster caused by the activation of the Pandora Box resulted in Japan being split into Touto, Seito and Hokuto, which would then cause the beginnings of the Japanese Civil War.

Humans

 * Takumi Katsuragi
 * Sento Kiryu
 * Kazumi Sawatari (Deceased)
 * Misora Isurugi
 * Soichi Isurugi
 * Sawa Takigawa
 * Gentoku Himuro
 * Taizan Himuro (Deceased)
 * Nariaki Utsumi (Deceased)
 * Shingo Kuwata (Deceased)
 * Eita Kawai
 * Masahiro Nabeshima
 * Tomoe Nabeshima
 * Haruka Nabeshima
 * Juzaburo Namba (Deceased)
 * Yoshiko Tajimi
 * Masakuni Mido (Deceased)
 * Kaisei Mogami (Deceased)
 * Akaba (Deceased)
 * Aoba (Deceased)
 * Kiba (Deceased)
 * Fu Washio (Deceased)
 * Rai Washio (Deceased)
 * Masuzawa (Deceased)
 * Kyoichi Shimizu (Deceased)
 * Kasumi Ogura (Deceased)
 * Reika Kine
 * Tatsuya Kishida
 * Taro Satou (Deceased)
 * Takehiko
 * Shinobu Katsuragi (Deceased)
 * Kyoka Katsuragi
 * Massugu Ubukata
 * Koji Hotei (Deceased)
 * Yuri Banjo (Deceased)

Other

 * Vernage
 * Evolto
 * Ryuga Banjo
 * Parado (From the World of Ex-Aid, formerly)
 * Kengo Ino (Deceased)
 * Mitsuomi Gohara (Deceased)
 * Ryoka Saiga (Deceased)

Locations

 * Earth
 * Japan
 * Touto
 * nascita
 * Barber Kiryu
 * Hokuto
 * Sawatari Farm
 * Seito
 * Mars
 * Evolto's planet

Organizations

 * Institute of Space Engineering Technology
 * Namba Heavy Industries Ltd.
 * Faust
 * Touto Institute of Advanced Matter Physics

Devices

 * Pandora Box
 * Skywall
 * Evol-Driver
 * Evolbottles
 * Evol Trigger
 * Prominence
 * Nebulasteam Gun
 * Gears
 * Transteam Gun
 * Build Driver
 * Fullbottles
 * Sclash Driver
 * Sclashjellies
 * Hazard Trigger

Transformations

 * Rider Systems
 * Kamen Rider Build
 * Kamen Rider Cross-Z
 * Kamen Rider Cross-Z Charge
 * Kamen Rider Cross-Z Magma
 * Kamen Rider Great Cross-Z
 * Kamen Rider Grease
 * Kamen Rider Rogue
 * Kamen Rider Evol
 * Kamen Rider Mad Rogue
 * Transteam System
 * Night Rogue
 * Blood Stalk
 * Kaiser Systems
 * Bikaiser
 * L Kaiser
 * R Kaiser
 * Nebula Hell Bro's
 * Hell Bro's
 * Engine Bro's
 * Remocon Bro's
 * Smash
 * Fang Smash
 * Needle Smash
 * Strong Smash
 * Strong Smash Hazard
 * Burn Smash
 * Flying Smash
 * Flying Smash Hazard
 * Mirage Smash
 * Square Smash
 * Press Smash
 * Press Smash Hazard
 * Ice Smash
 * Stretch Smash
 * Stretch Smash Hazard
 * Lost Smash
 * Owl Lost Smash
 * Stag Lost Smash
 * CD Lost Smash
 * Scissors Lost Smash
 * Zebra Lost Smash

Constructs

 * Clone Hell Bro's
 * Clone Smash
 * Press Clone Smash
 * Stretch Clone Smash
 * Strong Clone Smash
 * Flying Clone Smash
 * Guardians
 * Hard Guardians

Behind the scenes
As established from the first episode, the Sky Wall Disaster of ten years prior had extreme effects on Japan which were not present in prior Kamen Rider Series. Ultimately, the film Kamen Rider Heisei Generations FINAL: Build & Ex-Aid with Legend Riders confirmed that Kamen Rider Build took place in its own world separate from the prime reality or World of Ex-Aid, home to Ex-Aid as well as the various Legend Riders such as Ghost, Gaim, Fourze and OOO.