Nightmare City (ナイトメアシティ) is the action-packed duology which borrows 2channel's AA characters. The two Flash animations were authored by “Mi~ya” (み～や), under “Clairvoyance”, and was published for events on December 25, 2004 and October 29, 2005.¹⁾

The animation was quite popular and received a lot of parodies, including “4chan City” by “NCHProductions”, but it also drew in some criticism for alleged plagiarism at the time. For their 20th anniversary, it had a remaster that released on December 25, 2024.²⁾³⁾

Most of the original story can be inferred from the first animation's bonus cutscene, where it's explained that the protagonists are stuck in cyberspace, so their 'dreams' or 'minds' are all connected, but the machine malfunctions since the AIs started to rebel, which meant that nobody has been able to wake up, and we're left with a brief hint that one must realize they're dreaming from within a dream.

As the story goes, the protagonists attempt to escape a virtual 'city of lies',⁴⁾ and most of the characters are implied to be humans using AA characters as mere avatars. However, this Shii cannot escape with “Giko” because she was an AI herself, the 'Monolith-C' (Monolith-Shii) machine.⁵⁾ In the end, they finally defeat said machine, which does free everyone, but deletes Shii in the process.

^{Key: O - Original, C - Catastrophe, R - Requiem. ⭕ - Does appear, ❌ - Does not appear, ⏪ - Flashback only.}

Toggle transcript and literal translation.

The initial Nightmare City was submitted to the 'Third Red-White Flash Contest' on December 25, 2004 and won first place, netting him an iPod Mini and interview within the 2channel Plus magazine.⁶⁾ Months later, Miyasuke had became a special guest for 'FLASH★BOMB '05' on October 29, 2005, which is when the second half and dramatic conclusion, Nightmare City: Catastrophe, was initially unveiled.

Nearly two decades later, Miyasuke would post about a Nightmare City-inspired VR project for April Fools Day 2021, and most people assumed this was a joke.⁷⁾ For the 20th anniversary, Miyasuke would upload a remaster as Nightmare City: Requiem on December 25, 2024, and the VRChat world shown earlier would become public for brief periods of time.⁸⁾

The animations borrow music from the indie Japanese metal band, 403 (Yonmarusan), who initially released “Southern Cross” and “Northern Lights” into the public domain, but eventually organized these tracks in the 2007 album, N.E.W.S., then remastered them. For the 20th anniversary remaster, the new animation uses “Raise Your Souls!” from the 2021 album Heroes Part 2, as it has the “Southern Cross” leitmotif.

Upon winning the contest, the first Nighmare City was criticized for plagiarism or a lack of originality, as the work allegedly references Akira,⁹⁾ Final Fantasy,¹⁰⁾ Kingdom Hearts, Savior Cat, etc. This non-issue caused a mild commotion, so Miyasuke felt obligated to apologize for the commotion during an interview on an internet radio program in 2005.

• In the past, the band name '403' was mistakenly written as '403 Forbiddena', presumably since their former website was "Laboratory Room 403 -Forbiddena-" (研究室403号室 -Forbiddena-).
• Giko's actual human name was planned to be 'Kōsuke Kusanagi' (草薙コウスケ, Kusanagi Kōsuke).¹¹⁾
• Miyasuke did “Monosugoi Ikioi de Keine ga Monosugoi Uta” (物凄い勢いでけーねが物凄いうた).¹²⁾¹³⁾

• Savior Cat - One of the inspirations.

• Nightmare City → Catastrophe - The original Flash files. Yes, it's still there.
  • Nightmare City → Catastrophe + Requiem on Niconico Douga - The official uploads.
  • Nightmare City → Catastrophe + Requiem on YouTube - The official uploads.
• miyasuke.net - The front page of Miya's website. Hasn't been updated in years. Mostly retired.
  • @miyasuke1 on Twitter
• Laboratory 403 - The front page of 403's website.
  • @kazuki403 on Twitter
• Nightmare City on Pixiv Encyclopedia
• Nightmare City on Niconico Encyclopedia