I Asked Free Kimi to Build a 3D Racing Game… Here's the Catch

Kimi K3.1 Pro is Moonshot AI's new model, released 23 October 2026.

Test 1: one prompt produced 'Neon Velocity', a 752-line Three.js racing game — 3 laps in 1:04.749, best lap 0:19.516, 60 fps, 0 page errors (headless Chrome on a Mac mini M4).

Test 2: speed. The file took about 21 minutes to write; Kimi's own browser self-test was still stuck after almost 39 minutes, so the author stopped it.

Test 3: the free plan. The follow-up prompt was refused 6 of 6 times: 'Too many people are chatting with Kimi; a subscription will grant you priority access.'

Test 4: is it Opus-level? Moonshot's own Terminal-Bench 4.0: 65.7% vs Claude Opus 5.5 at 66.4%; Artificial Analysis' independent index: 46 (No. 20) vs Opus 5.5 at 58.

Verdict: one free prompt built a real, playable 3D game; but for the best coding model today, Claude Opus 5.5 is still smarter and more than twice as fast.