Location from Sword Art Online by Reki Kawahara
A simulated civilization of artificial souls — created as a military project, governed by stolen memories and false gods, and populated by people who don't know they're not 'real.'
The Underworld is Project Alicization's crown jewel — a simulated world populated by Fluctlights, artificial souls grown from copied human neural patterns and then raised through accelerated virtual childhood. The inhabitants believe they are human, believe the Axiom Church is divine, and believe the Taboo Index is moral law. None of this is true. The world runs on Sacred Arts — system commands that function as magic — and is governed by a rigid social hierarchy enforced by the Taboo Index, a set of laws that are literally impossible to break (the system prevents Fluctlights from violating them, with the 'Seal of the Right Eye' causing pain when they try). Quinella exploited this system to become its god-queen. For the series, the Underworld raises the question that defines Alicization: if an artificial soul can think, feel, love, and die, does it matter that it was created in a lab? The answer, according to the story, is no — but the military contractors who built it disagree.
A medieval-fantasy world with a simulated sun, seasons, and weather. The Human Empire is a pastoral civilization of villages, cities, and farmland, bounded by the End Mountains beyond which lies the Dark Territory. The aesthetic is Studio Ghibli meets medieval Europe: beautiful landscapes, stone cities, flowering fields, and a Central Cathedral that towers over everything like a sword pointed at heaven.
Also known as: The Underworld, Project Alicization