Claude Opus 5.5 and Claude Haiku 5.5 got the same prompt in Claude Code, one try each. Nobody edited the code. Play both (desktop browser, click to lock the mouse; WASD, space, left/right click):
The prompt (copy it and try it yourself):
Make me Minecraft that runs in my web browser, as one index.html file. I want to walk around a blocky world, jump, break blocks and place blocks. Make it look good. Test it yourself before you tell me it's done.
Watch the test: Claude's Biggest AI vs Its Smallest AI: Make Minecraft From Scratch (Agent at Work).