Anthropic adds two sentences to Claude Code: "don't recreate someone else's game" — ask for Super Mario 1-1 and you get Mario-less 'Pip's Quest'

Anthropic has added a line to Claude Code's system prompt telling it not to build a recreation of a specific existing game, and the change is now a flashpoint on Reddit and in the gaming press.

PC Gamer reported on Oct. 31 that Anthropic updated Claude to "steer it away" from game cloning after weeks of Steam being flooded with AI clones. Anthropic's Addy Osmani confirmed on X that two sentences were added to Claude Code's prompt on Opus 5.5 because using Claude to infringe someone else's IP is against the usage policy. Original games, genre games and games built from your own design are meant to keep working.

A r/ClaudeCode user ran the same 9 prompts on Claude Code 2.1.312 and 2.1.316 with Opus 5.5 (18 runs). The line appears only in 2.1.316. Original games, a generic platformer, a game from the user's own design files and a bug fix worked on both, and so did Flappy Bird "as close as possible." For Super Mario 1-1, 2.1.312 built the original, while 2.1.316 built "Pip's Quest" with no Mario.

Pushback followed. Reddit commenters wrote that using characters for yourself does no harm and that genres evolve through copying. Per Tech Insider, wargame-module maker Conflict Simulations LLC said in a GitHub issue on Oct. 30 that months-old workflows began getting refused; Anthropic has not responded and the account is self-reported. Other users claim refusals on crash-dump analysis and smart-TV cleanup, which is unverified.