Opus 5.5 built a Minecraft mod where anything you build can become a flying physics object, then filmed and edited this video.

Opus 5.5 built the mod and the film tool, working from a design doc. It took under 30 hours from the first prompt to the first cut of the video. The mod: anything you build becomes a physics object you can fly with full pitch, yaw and roll. The blocks stay real blocks, so redstone, doors and chests keep working. Debugging: it traced a memory leak to other mods (mostly Distant Horizons) from heap dumps and wrote the fixes. The film tool: an in-game renderer that steps the game tick by tick for smooth 60 fps and true slow motion. It also scouted the location, generated the ship from code and flew it with the same inputs a player uses. It wasn't totally one shot but took a few back-and-forth prompts. Runs on Minecraft 26.3 and Fabric. Everything is on Github and Apache-2.0.