Anthropic has introduced a new rule within its Claude Opus 5.5 AI model to prevent users from creating recreations of existing video games. This update, flagged internally as "tengu_heron_brook," specifically instructs the AI to safeguard against prompts that result in "a recreation of a specific existing game, even if it is renamed or called original."
The change was reportedly noticed by users who found the AI's ability to work with tools like Reverse Engineer Anything, previously used for decompiling and open-sourcing games, had been diminished. While Anthropic has not released an official statement detailing the new rule, its presence in the Claude Opus 5.5 changelog from October 27 confirms its implementation.
The new restriction allows users to create original games, games within a specific genre, or games based on their own designs and assets. However, it actively blocks attempts to replicate existing titles. For example, while a user could ask Claude to create a racing game, asking for a game "like Need For Speed" would likely trigger the AI's guardrails.
Reports from users on platforms like Reddit and X suggest that Claude's restrictions may extend beyond game recreations. Some users have encountered refusals to process information from unlicensed translations of web novels, with the AI citing illegality and immorality. This indicates a broader move by Anthropic to implement stricter safety classifiers that could impact access to various types of content, potentially in response to user actions and their associated implications.