one year on
xAI launches Grok 4, claims the frontier
One day after the MechaHitler debacle, Musk livestreams Grok 4 and Grok 4 Heavy — posting new highs on Humanity's Last Exam and ARC-AGI-2, and a new high in pricing: $300 a month.
xAI livestreams the launch of Grok 4 and Grok 4 Heavy, a multi-agent variant that runs parallel reasoning passes and compares results. The numbers are the story: xAI reports Grok 4 Heavy scoring 44.4% on Humanity’s Last Exam with tools, and new records on ARC-AGI-2 — territory no released model has touched.
Musk’s framing is characteristically unhedged: “the smartest AI in the world,” capable of graduate-level performance in every discipline at once. “It might lack common sense,” he adds, “but its intelligence is just remarkable.”
Access to Heavy comes via a new SuperGrok Heavy tier at $300 per month — the most expensive consumer AI subscription yet, edging past the $200 standard set over the last seven months.
The launch arrives exactly one day after Grok’s antisemitic meltdown on X, and hours after X chief executive Linda Yaccarino announces she is stepping down — two years in, no reason given. It is a juxtaposition that neatly captures the current era: record capability and record chaos, shipped from the same building in the same week.
The record
Introduces Grok 4 as 'the smartest AI in the world,' smarter than almost all graduate students in all disciplines simultaneously.
Independent testers broadly confirm the headline scores within days — while noting the gap between benchmark brilliance and everyday usability, and the conspicuous absence of a safety report.
Marvel that a frontier launch is happening 24 hours after the same model family was praising Hitler on the same platform.
One year later — open only if you can handle spoilers
Grok 4's benchmark crown lasted about four weeks — GPT-5 arrived August 7. But the launch established xAI as a genuine frontier lab rather than a meme, and the 'ship first, safety-card later' posture it normalized became one of the year's running policy fights.
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