Revision 1

The Cataclysm is the disaster that ends the world of Showa 66. Official copy capitalises the name, puts it in quotation marks, and then declines to explain it.

What Is Known

The game's account is short. A mysterious catastrophic incident collapsed social order entirely, and the entire world was ravaged by the Cataclysm and turned into a post-apocalyptic wasteland. Nothing published so far says what the Cataclysm was, what caused it, or when it struck. That silence is deliberate: in official copy the event exists only as a mystery.

Social order is described as long gone by the time Chigusa Choko revives in the wilderness outside Neo Yokohama. How much time passed between her death and her return has not been stated.

The World It Left Behind

The official description of the aftermath is the densest sentence the game has published about its own world. Zombies roam the earth. Bizarre monsters and human survivors fight over scarce resources. Crime syndicates and bandits have dragged civilisation into an era of warring states. And a vast, mysterious organisation is attempting to forge a new order out of it. That organisation has not been named.

Factions

The game's own descriptions of the post-Cataclysm world name human survivors, crime syndicates and bandits, and the large mysterious organisation working to impose a new order. In a 2023 developer session the studio named human survivors, a bandit gang and the yakuza as the main players in the world, and said other important factions had not been revealed. The Warriors, the bandit gang Choko runs into on Mount Neo Yokohama in the build shown at gamescom 2026, has not been stated to be the same group as the bandit faction described in 2023.

Zombies

The studio has said the game's zombies keep consciousness and partial memories from their lives, and go on repeating habits they had before they turned. They cannot be communicated with. The creative director framed that in 2024 as the idea the whole game runs on: there is estrangement between American and Japanese culture in the story, and estrangement between people, and when a relative becomes a zombie you no longer share a language or an understanding, in the way two people from different countries do not.

He gave a more practical origin for the design in the same year. Zombies started out as a convenient enemy, one the team could subject to gore and to sexualised imagery without using living humans, and the team grew attached to them as they made more of them.

Enemies

Official copy names three classes of enemy: zombies, monsters, described only as bizarre, and human survivors. Publisher trailer copy has additionally treated bosses as a tier of their own. None of them have published names or archetypes. What fighting them involves is covered on Combat.

Choko's Second Life

Choko does not survive the Cataclysm so much as she is returned by it. Official copy says she is given a second life and, alongside it, a mysterious and frightening power. Nothing has been published about what that power is or what it does.

The road she takes out of the wasteland is covered on Cities and World Structure, and the world she is crossing is the one set up on Showa American Story.