Ethan Mollick reports that the generative design tool Fable produced a playable 'Piranesi' city-builder that realizes a concept he had faked in an AI video the prior year. The standout mechanic lets players create arch-and-waterway cities among cyclopedian ruins and invite humans to live there; a demo is available at capriccio-city.netlify.app.
Ethan Mollick (@emollick) says Fable generated a playable 'Piranesi' city-building game on July 27, 2026, matching a concept he previously faked in an AI demo video last year.
Fable built me the Piranesi city building game that I faked in an AI video last year. The key mechanic the AI came up with is building a city of arches and waterways in cyclopedian ruins & inviting humans to live amongst them.
This one impressed me. Play: capriccio-city.netlify.app/
Video
Ethan Mollick (@emollick)
Piranesi city builder game
Video
— https://nitter.net/emollick/status/1901819513403810102#m