No, this is exactly what Claude vibe codes, this is definitely a one-shot Claude style game (assuming it looks up a decent pixel art pack). LLMs are pretty decent these days at making standard game clones like this, you just have to add a system prompt about making it look like a real indie-style pixel art game instead of just letting it make it's standard "web game" style. I assume google has a good background system prompt/harness to do this automatically.

This played waaaay better than a one-shot Claude style game but I'm sure it was not one-shot either.