Opus 5 vs GPT-5.6 Sol vs Kimi K3: Flappy Bird

We ran a test between Opus 5, GPT-5.6 Sol, and Kimi K3. One prompt. Across all three models. With our /design command. Results: We reviewed gameplay, UX, and UI

• Opus 5 is strong UI + motion, best gameplay
• Kimi K3 has solid design and gameplay
• GPT-5.6 Sol has best UI, worse gameplay

Ranking (DX, features, and cost):

• Opus 5: 10/10 · $0.25
• Kimi K3: 9.5/10 · $0.12
• GPT-5.6 Sol: 7/10 · $0.32

Our engineering and design team has been testing 20+ side-by-side comparisons across frontier and open models. All runs are public and open source. Benchmark for this demo here: github.com/CommandCodeAI/slash-design-showcase/tree/main/flappy-bird/light-version

Try Command Code

The best coding agent for open models, in your terminal or on your desktop.

Desktop App · Docs · X · Discord