We already have access to a smaller version of the Mythos tier with Opus 4.7: based on the usual delta between the full fat models and their distills, do you really think Mythos breaks cybersecurity?

It's a good model update. We've had these before, and it looks like OpenAI is gearing up to match it this week.

Mythos launch has felt like a showsman overlplaying their hand.

Opus 4.5 put them in an awkward position after everyone went Opus-only and suddenly Sonnet's quota was getting treated like you were asking people to use Haiku.

So a new pretraining run completes and instead of just releasing it as Opus 5, they stick the model in a new tier and name it Mythos Preview, while simultaneously launching Project Glasswing to literally build a mythos around the model.

Some people are even confusing it for some sort of completely new paradigm of model centered on cybersecurity not realizing it's 'just' a new model tier, and the cybersecurity stuff is separate.

While Mythos Preview is simmering a Sonnet-sized distill gets launched as Opus 4.7, at Opus prices, and fixes the margins and compute needs of the Opus tier again.

Improved pretraining + progress on RL allows it to compete even though it's a smaller model, but some things still regress like understanding nuance (hence the regression on Tau bench and agentic search)

It's clear they plan to price Mythos like they used to price Opus (so high that you don't see it as a strict replacement for the smaller tiers) and heal the compute crunch just a tad.

The main problem is OpenAI doesn't have to play these games.

They have compute, and GPT-5 is already a very parameter efficient model so they're just going to release their model without the fanfare and mystery.

Mythos might get deflated before they even get to cash in on all the fanfare they created. Unfortunate timing really (if you're Anthropic)

A Boy That Cried Mythos: Verification Is Collapsing Trust in Anthropic