OpenAI Drops GPT-5.6 Series: Sol, Terra, and Luna Enter Preview
OpenAI launches three new GPT-5.6 models with Sol matching Mythos Preview on ExploitBench and packing new Ultra mode.
OpenAI is rolling out a limited preview of its GPT-5.6 lineup — three models, each carved out for a different use case.
Sol is the flagship beast. It matches Mythos Preview on ExploitBench, which is no small feat. It also introduces Ultra mode, deploying subagents to handle complex multi-step workflows, plus a max reasoning mode built for deep problem-solving tasks.
Terra sits in the middle — a balanced model designed for everyday work. Luna rounds out the trio as the fast, budget-friendly option.
The three-tier approach signals OpenAI doubling down on segmentation. Not every task needs the full firepower of a flagship model, and not every user wants to pay for it. Sol for the heavy lifting, Terra for the daily grind, Luna for speed and cost efficiency.
Access is limited for now. No word yet on broader availability.