AI Roundup April 2026: Claude Mythos, GPT 5.5, Musk-Altman lawsuit, and more

April 2026 is likely to go down in history as one of the most crucial months in the field of AI tech in 2026. This month introduced us to a variety of developments, with some focusing on making AI more friendly and easier to access, while other players gave a teaser of the model’s dangerous side.

From capabilities to safety concerns, the AI space has seen some action. Anthropic’s Claude Mythos dominated the headlines throughout most of the world, with OpenAI playing catch-up with its GPT-5.4 Cyber.