One prompt, 321 lines: Opus 5.5 builds a playable flight simulator in a single HTML file

EricBuess · x · 2026-09-27

A user gave Opus 5.5 a single prompt — "build a flight simulator over endless procedural mountains" — and reportedly got a playable game in one 321-line HTML file, with just one bug fixed manually. No 3D models or prebuilt maps: mountains, lakes, forests and snow lines are all generated from noise in real time as you fly. Reposters add that an RPG one-shotted by the same model came with graphics and audio produced entirely by Claude.

Original post →

More from coding & agent

coding & agent channel →