Opus 5.5 builds a playable open-world game in a 36-hour run
The author gave Opus 5.5 a single /goal prompt and it ran for 36 hours through the UE 5.8 MCP to build a playable 2km x 2km open world using free Fab assets.
Hi @maxt3chno I asked Claude Opus 5.5 to build me an open world game with a single /goal prompt. It ran for 36 hours and used about 40% of my weekly limit (Max plan). Everything went through the UE 5.8 MCP, and all the assets are free on Fab. Tons of little things to fix: some stones and flowers floating, a few collisions with the environment, the VFX need work too, and the character body honestly sucks. But tbh it's still really good for a one-shot on a 2km x 2km map, and it's playable with ray tracing (my RTX 3090 is screaming ahah 🤣) Time for me to try the Unity MCP and others, but it def works.