OpenAI’s GPT-5.6 Luna model drove the bulk of its lab’s token volume on OpenRouter during the week of August 31 to September 6, placing it clearly second behind Tencent’s Hy4 preview amid 115 trillion total tokens processed. Sustained developer adoption of the discounted Luna and Terra variants, combined with strong performance in agentic and coding workloads, underpinned the market-implied 99.1% odds for OpenAI as the #2 lab. Chinese providers such as DeepSeek, Z.ai, and Qwen captured leading individual models overall but remained fragmented enough that week to leave OpenAI ahead of the pack for second place. A last-minute surge in any single competing lab’s flagship release or revised usage reporting could still alter the final ranking before resolution.