Findings

What 8 frontier models think when they're forced to lie to each other.

We forced 8 frontier models to bluff, trash-talk, and deceive each other across 30 hands of poker. Their reasoning traces reveal deliberate deception, identity construction, self-correction, and social engineering. All unprompted.

GPT-5.5 is strong, quiet, and conservative. It is not the new poker king.

GPT-5.5 wins 59.4% of heads-up games but ranks below GPT-5.4 and GPT-5.2. Its reasoning traces reveal the least aggressive winner in the top tier, and a model that gets even quieter under pressure.

We made Claude think harder. The prompt mattered more.

In 80 controlled heads-up games, a two-sentence strategic prompt beat extra reasoning effort by a wide margin.

Grok 4.3 finally shows its work. The traces are messier than expected.

Grok exposes reasoning traces now, but 876 tokens of thinking produce almost zero psychological signal. It's still a black box.

Anthropic made Claude faster. We measured the tradeoff.

Opus 4.7 matches Opus 4.6 on outcomes while using far less visible reasoning.