As a result, an alternate persona called Parad manifested from Emu's desire for a playmate and assumed control, leading to the latter becoming "M" and being kidnapped by Next Genome scientists who had sought to extract the Bugster Virus for Kuroto.
Despite being separated from Parad, trace amounts of the Bugster's data causes Emu to maintain his gamer persona, become a Kamen Rider, and later grant him the ability to create Gashats from his imagination.
Moreover, activating Mighty Action X generates a Game Area (ゲームエリア, Gēmu Eria) digital field and several Energy Item (エナジーアイテム, Enajī Aitemu) medals with unique power-ups randomly hidden inside chocolate block-like containers.
During the first Zero Day incident, Momose was infected with the Bugster Virus, but she had kept it secret from Hiiro due to his aloof attitude until he eventually learned what had happened when Graphite manifested from her.
During the events of the V-Cinema, Kamen Rider Ex-Aid Trilogy: Another Ending, Hiiro reconciles with Taiga before joining forces with him to defeat Lovrica, who had brainwashed a temporarily resurrected Momose.
While transformed, she can wield the Gashacon Bugvisor II, possesses immunity against conventional attacks, and perform the Critical Crews-Aid (クリティカルクルセイド, Kuritikaru Kuruseido) finisher.
Five years prior to the series, while working for the Seito University Hospital's radiology department, he had been chosen by CR to become a Kamen Rider after detecting the Bugster Virus in one of his patients.
However, Kuroto's mother Sakurako also became infected with the Bugster Virus while helping him and died, leading to him losing his sanity, causing Zero Day via Proto Gashats (プロトガシャット, Puroto Gashatto), and framing Masamune for it five years prior to the series.
During the events of the V-Cinema, Kamen Rider Ex-Aid Trilogy: Another Ending, Kuroto uses his last life to initiate a universal apocalypse through a multiplayer survival horror game called Zombie Chronicle (ゾンビクロニクル, Zonbi Kuronikuru).
During the events of the two-part web-exclusive special Kamen Rider Genms: The Presidents, which takes place after the series, an artificial intelligence called the Ark digitally revives Kuroto, who infects Gai Amatsu with a unique strain of the Bugster Virus in order to materialize himself in the physical world and regain control of Gemn Corp. so he can use it for malicious means.
During the events of the web-exclusive special Kamen Rider Genms: Smart Brain and the 1000% Crisis, Kuroto is revived as a Humagear and manipulates Amatsu into transferring control of the latter's company, Thouser-Intellion, to him under the Ark's orders.
Moreover, activating Proto Mighty Action X generates a Game Area and several Energy Items randomly hidden inside chocolate block-like containers.
When Masamune Dan reveals he had manipulated everyone involved in Kamen Rider Chronicle and kills one of his fellow Bugsters, Parad becomes fearful of suffering the same fate and confronts Emu, who defeats and reabsorbs him.
Utilizing the double-sized Gashat Gear Dual (ガシャットギアデュアル, Gashatto Gia Dyuaru), which generates a Game Area with several exposed Energy Items, Parad can transform into Kamen Rider Para-DX.
During the events of the web-exclusive miniseries Kamen Sentai Gorider, Kuroto arranges the resurrection of Kiriya, among other deceased Riders, to lure Emu Hojo to the Game World and kill him.
During the fight, Kiriya transforms into the yellow-colored Kirider (キライダー, Kiraidā) before joining the fallen Riders in sacrificing themselves to defeat Kuroto and ensure Emu and Kazuma's escape.
In the V-Cinema, Kamen Rider Ex-Aid Trilogy: Another Ending, Kuroto revives Masamune to force him to help the former develop Zombie Chronicle in order to destroy the universe and serve as a host for Black Parad.
Unless their corresponding Bugster is destroyed or dealt with quickly, the host will turn into data and the former fully manifests with additional powers, such as the ability to assume human forms.
After losing face with Kuroto Dan, Graphite steals the Proto Drago Knight Hunter Z Gashat to evolve himself and attempts to spread the Bugster Virus on a larger scale, only to be defeated by Hiiro, Taiga, Emu Hojo, and Kiriya Kujo.
When Masamune Dan takes over Kamen Rider Chronicle for himself, Graphite obtains a sample of the game's final boss, Gamedeus, and infects himself with it to cultivate the virus.
In the present, Masamune Dan steals the Proto Gashats from the Ministry of Health and bribes Hiiro into helping him maintain Kamen Rider Chronicle by promising to restore Saki.
During the events of the V-Cinema Kamen Rider Ex-Aid Trilogy: Another Ending, Kuroto temporarily resurrects Momose, but a similarly revived Lovrica subsequently brainwashes her.
With support from his coworkers on the development team and the new CEO, Ren Amagasaki, they complete the game using Kuroto's private terminals, though Koboshi is infected with the Bugster Virus.
Tōgo Kiyomiya (清宮 東吾, Kiyomiya Tōgo) is a high school student and computer programming prodigy who developed the Hate Sate Puzzle (ハテサテパズル, Hate Sate Pazuru, Well Well Puzzle) video game and appears exclusively in the crossover film Kamen Rider Heisei Generations: Dr. Pac-Man vs. Ex-Aid & Ghost with Legend Rider.
Due to his being a carrier of a new strain of the Bugster Virus, the Next Genome Institute kidnap Kiyomiya, but the latter is rescued by Kamen Riders Ex-Aid, Ghost, Drive, Gaim, and Wizard.
Consisting of the red-colored Akarider (アカライダー, Akaraidā), the blue-colored Aorider (アオライダー, Aoraidā), the yellow-colored Kirider (キライダー, Kiraidā), the pink-colored Momorider (モモライダー, Momoraidā) and the green-colored Midorider (ミドライダー, Midoraidā), the team incorporates traits from the first Sentai, Himitsu Sentai Gorenger, and Kamen Riders 1 and 2 from the original Kamen Rider television series and transform via Gorider cards.
In the Kamen Sentai Gorider miniseries, Emu transforms Kaito Kumon, Kazuma Kenzaki, Kiriya Kujo, Yoko Minato, and Kaoru Kino into Akarider, Aorider, Kirider, Momorider, and Midorider respectively to assist him in defeating a backup copy of Kuroto Dan and his monstrous ally Totema.
Machina Vision (マキナビジョン, Makina Bijon) is a foreign video game company that develops advanced VR technology and cooperated with Genm Corp. in the distribution of Kamen Rider Chronicle in exchange for a Gamer Driver from Masamune Dan.
The Ninja-Players (忍者プレイヤー, Ninja Pureiyā) are Nagumo's henchmen consisting of individuals that he infected who appear exclusively in the film Kamen Rider Ex-Aid the Movie: True Ending.
Johnny Maxima (ジョニー・マキシマ, Jonī Makishima) is the mysterious CEO of Machina Vision who aligned himself with Masamune Dan amidst the Kamen Rider Chronicle crisis.