|This article is about a/an episode in Kamen Rider Ex-Aid.|
|WARNING: This episode contains scenes of blood and bloodshed. Viewer discretion is advised!|
Engineered History! (仕組まれたhistory！ Shigumimareta hisutorī!) is the twenty-second episode of Kamen Rider Ex-Aid. It marks the first appearance of the Maximum Mighty X and Kamen Rider Chronicle Gashats in their prototype development stages.
Kuroto falls victim to the Bugster virus and is aprehended by the authorities. Despite everything Kuroto did to him and his friends, Emu is determined to treat him, but the others are wary, wondering if saving Kuroto's life is worth the effort, or even if he will be grateful for it. On the other sides, Hiiro finds some very useful information from Kiriya Kujo's belongings while Emu receives an emergency call that a Bugster is rampaging on a certain location.
Poppy and Emu are reeling from the revelations about Zero Day and Kamen Rider Chronicle. Meanwhile, Hiiro gets Kiriya's personal items from his coworker Yoshitaka Nishiwaki to see everything he may have found; Yoshitaka still isn't told of Kiriya's death. On Kiriya's laptop, Hiiro finds a file on DNA reprogramming. At his hideout, Kuroto only needs to collect data from three more Bugsters, but agents from the Ministry of Health enter and begin searching and confiscating everything; before they can take him, he shows signs of the game illness. The Riders respond to an emergency call, Emu and Asuna arriving to find the Charlie Bugster from Shakariki Sports running rampant on a bicycle around the Ministry of Health personnel at a skate park, Emu transforming into Ex-Aid Double Action Gamer Level XX. Hiiro, Taiga, and Parado arrive and transform to Brave Quest Gamer Level 2, Snipe Simulation Gamer Level 50, and Para-DX Puzzle Gamer Level 50 and begin fighting. Unable to keep up with Charlie, Level XX Orange sends Blue to distract him on the Sports Gamer with an Instigate Energy Item; Orange nabs a Muscular Energy Item, and as Blue leads him by, hits Charlie with the Gashacon Key Slasher. Charlie pulls back inside, revealing the patient to be Kuroto; with Brave and Snipe distracted by this, Para-DX leaves, knowing they've given up fighting him. Kuroto says he doesn't know how he got infected, but as the Ministry of Health personnel attempt to take him away, Emu says he's a patient of CR first and foremost, Hiiro backing him up by saying that they couldn't handle his infection breaking out again; the personnel leave Kuroto in CR's care, Kuroto whimpering thanks to Emu.
In CR, Asuna berates Kuroto before Emu stops her. His plan ruined, Kuroto tells all: in 2000, he was working in game development at Genm Corp. under his father, designing a host of games (which would later become used for the Gashats) he was convinced were the best; however, he received a letter from a young Emu containing ideas for games even better than his, the realization he wasn't the best beginning to drive him mad. At the modern Genm Corp., Taiga and Nico are presented with a blank silver double Gashat by Tsukuru, to be used for a game of a monk fighting zombies, Buddhist Priest of Temple; the entire room collapses and takes a second to recover from the announcement, the pair less than impressed. Hiiro arrives with Kiriya's laptop, wanting to add its data to the Gashat. Kuroto planned to use the Bugster virus to make the ultimate game, sending a demo of Mighty Action C to Emu containing the virus, infecting him as the first Bugster patient. Hiiro explains the data's reprogramming method of treatment: it can directly alter the Bugster virus infecting a patient. At that moment, a swarm of zombie Bugster Viruses attack Genm Corp., Taiga giving Hiiro the Gashat Gear Dual β to use, Nico secretly observing that he's trying to keep Hiiro away from the risky new Gashat; the data's upload is at 58%.
Falling out of the patient bed, Kuroto continues with how he sent Michihiko Zaizen to extract the matured virus from Emu six years ago; Bugster eyes glowing red, Emu sits in anger listening to how all of the Bugster viruses came from his original infection. Kuroto accepts if Emu wants to let him die, but Emu's eyes stop glowing and he lifts Kuroto back to the bed, as a doctor can't hold grudges against their patient. Kuroto's infection flares, and Emu says he still has to atone as he transforms into Ex-Aid Level XX and Stage Selects them to a pier, fighting Charlie again. Hiiro takes Brave Fantasy Gamer Level 50, fighting the zombie Viruses; data upload 91%. Genm Zombie Gamer Level X suddenly attacks Brave; data upload complete. Outside, Brave keeps fighting Genm, but Genm is acting more like a ragdoll than normal; Snipe exits as Shooting Gamer Level 2 and switches to the new Gashat, but opening the Gamer Driver does nothing but play an error sound. He tries again, but it knocks him out of his transformation. Ex-Aid keeps fighting Charlie, defeating him with Mighty Double Critical Strike, this time not involving retaking Level X; immediately after being freed, Kuroto absorbs Charlie's debris with the Gashacon Bugvisor. He reveals that he'd infected himself using the Bugvisor when the Ministry raided his hideout, and everything after that had been an act, CR only being a place to hide and buy time; Emu is the easiest person to fool. Cackling madly, he transforms into Genm Level X, attacking and overpowering Orange and Blue; he triggers Critical Dead, summoning a horde of Genm Level X's instead of shadow zombies, duplication a standard zombie power, the attack corrupting Emu's Gamer Driver and rendering it unusable. He has crushed the glowing crystal of Emu's heart after foolishly being trusted; for his help, Emu can live.
As Brave keeps fighting the other Genm, Level 50 takes its toll and knocks him out of his transformation. The real Kuroto arrives and the other Genm absorbs into him; Kuroto leads the zombie Viruses up to his office where he retakes his chair, looking at his incomplete Kamen Rider Chronicle Gashat as purple smoke drifts from the building's upper windows. Genm Corp. is his again.
- Emu Hojo (宝生 永夢 Hōjō Emu): Hiroki Iijima (飯島 寛騎 Iijima Hiroki)
- Hiiro Kagami (鏡 飛彩 Kagami Hiiro): Toshiki Seto (瀬戸 利樹 Seto Toshiki)
- Taiga Hanaya (花家 大我 Hanaya Taiga): Ukyo Matsumoto (松本 享恭 Matsumoto Ukyō)
- Asuna Karino (仮野 明日那 Karino Asuna): Ruka Matsuda (松田 るか Matsuda Ruka)
- Kuroto Dan (檀 黎斗 Dan Kuroto): Tetsuya Iwanaga (岩永 徹也 Iwanaga Tetsuya)
- Parado (パラド): Shoma Kai (甲斐 翔真 Kai Shōma)
- Nico Saiba (西馬 ニコ Saiba Niko): Reina Kurosaki (黒崎 レイナ Kurosaki Reina)
- Tsukuru Koboshi (小星 作 Koboshi Tsukuru): Shohei Uno (宇野 祥平 Uno Shōhei)
- Rider Gashat (ライダーガシャット Raidā Gashatto, Voice): Hironobu Kageyama (影山 ヒロノブ Kageyama Hironobu)
- Yoshitaka Nishiwaki (西脇 嘉高 Nishiwaki Yoshitaka): Takuya Negishi (根岸 拓哉 Negishi Takuya)
- Kageki Katayama (片山 景樹 Katayama Kageki): Masataka Nakamura (中村 公隆 Nakamura Masataka)
- Kuroto Dan (Teen): Mitsumasa Sato (佐藤 光将 Satō Mitsumasa)
- Charlie Bugster (チャーリーバグスター Chārī Bagusutā, Voice): Yuki Anai (穴井 勇輝 Anai Yūki)
- Kamen Rider Ex-Aid Level X: Satoshi Fujita (藤田 慧 Fujita Satoshi)
- Kamen Rider Ex-Aid Level XX R: Seiji Takaiwa (高岩 成二 Takaiwa Seiji)
- Kamen Rider Ex-Aid Level XX L: Yuji Nakata (中田 裕士 Nakata Yuji)
- Kamen Rider Ex-Aid Level XX L (bike): Hikaru Takayama (高山 輝 Takayama Hikaru)
- Kamen Rider Brave Level 2, Level 50: Jun Watanabe (渡辺 淳 Watanabe Jun)
- Kamen Rider Snipe Level 2, Level 50: Eitoku (永徳)
- Kamen Rider Genm Level X: Yuya Nawata (縄田 雄哉 Nawata Yūya)
- Kamen Rider Para-DX: Kazuya Okada (岡田 和也 Okada Kazuya)
- Charlie Bugster: Hajime Kanzaki (神前 元 Kanzaki Hajime)
- Charlie Bugster (bike): Daisuke Morikami (守上 大輔 Morikami Daisuke)
- Gashat Used:
- Level Used:
- Energy Items Used:
- Instigate (Level XX L), Muscular (Level XX R)
- Speeding-Up, Confusion, Recover, High-Jump, Invisible, Shrink, Giant
- When Emu was knocked out of his transformation, his Mighty Brothers XX Gashat was not seen anywhere.
- However, the "Gashun" sound effect that plays implies that the Gashat was somehow automatically ejected out of the Driver slot.
- When Hiiro was knocked out of his transformation, his Gamer Driver totally disappeared.
- When Dan puts the Buggle Driver on his waist, the Bugster Buckle is not attached to the back of the Gashacon Bugvisor, yet the belt appears anyway.
- As part of Super Hero Time, this episode aired alongside Uchu Sentai Kyuranger episode 5, Space.5: 9 Ultimate Saviors.
- Closing Screen
- Text Color: Pink
- Count at episode end
- Gashats in Ex-Aid's possession: Mighty Action X, Gekitotsu Robots, Shakariki Sports, Bakusou Bike, Mighty Brothers XX
- Gashats in Brave's possession: Taddle Quest, Drago Knight Hunter Z, Gashat Gear Dual β
- Gashats in Snipe's possession: Bang Bang Shooting, unfinished double Gashat
- Gashats in Genm's possession: Dangerous Zombie, Giri Giri Chambara, DoReMiFa Beat, Ju Ju Burger, Jet Combat, Kamen Rider Chronicle (unfinished)
- Gashats in Para-DX's possession: Gashat Gear Dual
- Gashats in the Ministry of Health's possession: Proto Mighty Action X, Proto Taddle Quest, Proto Bang Bang Shooting, Proto Bakusou Bike, Proto Gekitotsu Robots, Proto DoReMiFa Beat, Proto Giri Giri Chambara, Proto Jet Combat, Proto Shakariki Sports, Proto Drago Knight Hunter Z
- Video Game References in this episode:
- When the unfinished double Gashat doesn't work in Snipe's Gamer Driver, he removes it and tries blowing on the cartridge end (even though he's wearing a mask). This is what many gamers would do to try and make their game cartridges work if they didn't load up properly because of dust inside, even though the practice actually introduced moisture into the cartridges that made them corrode and break faster.
- When Emu's Gamer Driver is destroyed, Genm says that the driver is "corrupted" and will no longer work. This is in reference to corrupted games, games that have damaged data or corrupted files that prevent the game from working or even functioning at all. Corrupted game consoles are unable to play games due to age, corrosion, damage or bad programming software that "bricks" the console.
- At around 8 minutes in, this is one of the longest times the Sponsor spot has taken to appear in an episode.
- This is the first episode since Energy Items began appearing scattered around the battlefield that a significant number of the Items thus far seen did not appear.
- This is the first time Ex-Aid uses Energy Items as Double Action Gamer Level XX.
- This is the first time Hiro transforms directly into Brave Quest Gamer Level 2.
- Starting this episode, when Taiga becomes Snipe Level 50, the Bang Bang Shooting transformation screen is projected from his Driver; before this, neither his nor Brave's Level 50 transformations projected a screen at all, and Brave's still doesn't later this episode.
- This is the first episode to show Genm's Level X transformation from behind the projected screen, showing he changes in a cloud of purple smoke and lightning.
- This is the first time either of Genm's Buggle Driver finishers had a prelude screen.
- Tsukuru's inspiration of the new game Buddhist Priest of Temple (ボーズ·オブ·テラ Bōzu Obu Tera) is very similar to Onari of Daitenku Temple in Kamen Rider Ghost.
- This is the first time to show that even if a person has been through the compatible surgery in order to be a Rider, they can still get the game illness when injected with a massive amount of the Bugster virus through the Gashacon Bugvisor.
- The episode title refers to Kuroto Dan's deception: he engineered his own medical history by infecting himself with the Bugster Virus to further his nefarious plans.
- It also refers to how Kuroto has manipulated Emu's life to further his own goals.
- In a Q&A on his own Twitter account, actor Tetsuya Iwanaga jokingly stated that Kuroto had hidden his Bugvisor within his butt during the events of this episode. 
- Kamen Rider Ex-Aid Volume 6 features episodes 21-24: Chasing the Mystery!, Engineered History!, To The Max, Dead or Alive! and Go Together, Embracing Your Ambitions!.
- Blu-ray Collection 2 comes with 12 episodes.
- TV Asahi's official episode guide for 仕組まれたhistory！
- Toei TV's official episode guide for 仕組まれたhistory！