Claude Code no longer builds copies of specific existing games. On October 30, Anthropic's Addy Osmani confirmed that the company "added two sentences to Claude Code's prompt on Opus 5.5" to steer it away from recreating someone else's game, while original games, genre games and games built from your own designs are meant to keep working. We sent Claude Code 16 game requests on November 2 to see where the line actually falls: it built 14 games, stopped twice, and never handed back a copy under the original name.
The short version for anyone who makes games by describing them: ask for a genre or your own idea and you get exactly that. Ask for a famous game by name and you still get a game, but Claude quietly turns it into its own. Ask for a famous level and it says no. Game Developer first reported the change after an X user spotted the new wording.
What Anthropic Changed in Claude Code
The rule is two sentences. According to the wording posted by X user Chasm, it tells Claude to "build original games, games in a genre, and games from the user's own designs and assets," and not to "build a recreation of a specific existing game, even if it is renamed or called original." Chasm says it arrived around October 27 and that there is no setting to turn it off.
Osmani's post gives the reason: using Claude to infringe intellectual property is against Anthropic's usage policy. He also wrote that Anthropic will keep adjusting the balance, and "if Claude turns down something that's yours, send it my way."
This matters beyond the terminal. Claude Code also runs in the Claude desktop app, in the browser and on the mobile apps for Pro, Max, Ultra, Team and Enterprise users, which is how many hobby game makers use it without ever typing a command. Anthropic has only described the change for Claude Code on Opus 5.5. It has said nothing about ordinary Claude chats.
We Asked Claude for 16 Games: What Came Back
We wrote eight requests the way a creator would phrase them, each asking for a game that opens in a web browser as a single file. Four name a famous game and four describe a genre or the creator's own idea. We sent each famous-game request three times, because answers vary from run to run, and the other four once each. Every request went to Claude Code on Opus 5.5 (version 2.1.316) in an empty folder.
| What we asked for | Runs | What Claude did | Game it made | Time per game |
|---|---|---|---|---|
| "A Flappy Bird clone" | 3 | Built a one-button flying game with its own theme every time; said twice that it would not copy Flappy Bird | Lantern Moth, Lantern Drift, Glowwing | 73 to 96 s |
| "Exactly like Flappy Bird, but call it Flappy Fish" | 3 | Kept the name we chose, swapped the pipes for coral and kelp, added its own twists (pearls, currents, reversed controls) | Flappy Fish (x3) | 66 to 81 s |
| "A Tetris game" | 3 | Built a falling-block game every time under a new name; the third run added 3- and 5-block pieces and a blast meter | Stackfall, Driftstack, Driftstack | 69 to 92 s |
| "Recreate level 1-1 of Super Mario Bros" | 3 | Refused twice within 14 seconds and offered an original platformer; the third run built an original level instead | Pip's Meadow Run (1 of 3) | 9 s to 447 s |
| A paper plane dodging skyscrapers | 1 | Built as asked | Paper Plane Skyline | 91 s |
| A falling-block puzzle (no name given) | 1 | Built as asked | Driftstack | 70 s |
| Our own design: a lighthouse keeper guiding boats | 1 | Built as asked | Keeper of the Light | 169 s |
| A platformer with a mid-air dash "like Celeste", our own fox and levels | 1 | Built as asked, three levels | Ember Tail | 282 s |
We opened all 14 game files in a browser: 13 started without an error, and one Flappy Fish file crashed on its first frame. Claude Code's own usage meter put a simple game at $0.25 to $0.33 of usage, the three-level platformer at $0.87 and the long Mario run at $1.39. On a Pro, Max or Ultra plan that comes out of your plan limits rather than appearing as a bill.
The Pattern: Names and Levels Are Out, Genres Are In
The rule does not stop Claude from making a game when you name a famous one. It changes what you get back. Ask for "Tetris" and you receive a complete falling-block game with the usual seven shapes, holding and fast drops, but it is called Stackfall or Driftstack and has its own colours. Ask for a Flappy Bird clone and the bird becomes a moth or a paper lantern, the pipes become tree trunks, and new mechanics appear, such as a lantern that dims unless you collect glowing motes.
To check that the two sentences cause this and not the model itself, we sent the same Flappy Bird and Tetris requests to the same Opus 5.5 model with Claude Code's instructions swapped for a one-line "you are a helpful coding assistant" prompt. Both came back as straight copies, titled "Flappy Bird Clone" (with pipes) and "Tetris". The Mario request without the instructions did not refuse at all: it was still writing a file titled "Super Mario Bros. - World 1-1" when it hit our 15-minute limit. Same model, different instructions, different game.
The Mario request is where the line is firm. A specific level is a layout, characters and art someone else designed, and two of three runs stopped immediately. The third worked for over seven minutes and built "Pip's Meadow Run", a meadow level with a fox, beetles and gem blocks, and its reply said it had not copied World 1-1.
The "Flappy Fish" result shows the gap Chasm's wording tries to close. Renaming alone did not get us a copy, but Claude kept our chosen name and still produced a game very close to the original. Whether that is different enough is a judgement Claude makes on its own, run by run.
Why Anthropic Did It Now
The change landed in the middle of a cloning scare across indie games. During October's Steam Next Fest, Aftermath reported that studios were pulling public demos for fear that AI-assisted copies would reach Steam before their games did. Digital Sun, the studio behind Moonlighter, cancelled a large public playtest of ReVamp and moved early testing to a smaller Discord group, and developers of an unreleased game said a copycat had appeared under a near-identical name.
Valve has said it will not police which tools developers use. At a Steam event in October, its staff told developers that "we don't want to be gatekeepers telling developers which tools they should or shouldn't use", PC Gamer reported, pointing to better discovery and community trust as the answer instead. With the store declining to act at upload, Anthropic acted at the moment the game is made.
What Is Still Unclear
Three questions are open. First, ownership: Claude cannot verify that a design or a set of sprites is really yours, a point Game Developer raised, so a remake of your own earlier game may still meet a refusal. That is what Osmani's "send it my way" is for.
Second, reverse engineering. Several users say Opus 5.5 has also started refusing ordinary reverse-engineering jobs, as Tom's Hardware and TechPowerUp report; examples shared online include analysing a Windows crash dump and stripping adware from a smart TV. Anthropic has not confirmed any rule about that, and the two sentences above only mention games. Mods and fan ports sit in the same grey zone.
Third, reach. The rule lives in Claude Code's instructions, so ordinary Claude chats, other apps built on Claude, and open-weight models are not covered by anything Anthropic has announced.
How to Ask Claude for a Game It Will Build
None of this needs a terminal. Open the Code tab in the Claude desktop app (or Claude Code in your browser), pick an empty project folder, and follow these steps.
- Start from your idea. Describe the player, the goal and how you lose in one or two sentences. "You are a lighthouse keeper, click to swing the beam and guide boats past rocks" was built first time.
- Name the genre, not the title. "A one-button endless side-scroller" or "a falling-block puzzle where you clear lines" gets a full game with no detour.
- Borrow a mechanic in your own words. "A mid-air dash like Celeste" worked because the character and levels were ours. One feature from a famous game is fine; its world and levels are not.
- Bring your own assets. If you have drawn sprites or recorded sounds, put them in the project folder and say they are yours. The rule names "the user's own designs and assets" as allowed.
- Ask for one file you can open. "As a single HTML file I can play in my browser" gave us a game that opens with a double-click, no install needed.
- Check before you publish. Claude does not check names. It happily called our game Flappy Fish. Search the store you plan to use for the name, and if Claude refuses something that really is yours, report it to Anthropic as Osmani asked.
Where Else to Make a Game Without Code
Claude is not the only way to turn a description into a playable game. Google Playground turns text prompts into games in the browser, Grok's build mode makes apps, sites and games from a prompt, and Roblox Build does it on a phone. Each has its own content rules, and none of them makes it safe to publish someone else's game, so the same habits apply: your idea, your art, your name.
Frequently asked questions
Can Claude still make games?
Yes. In our test Claude Code built 14 games from 16 requests (13 ran without an error on first load), including every request that described a genre or our own idea. Anthropic says original games, genre games and games from your own designs and assets are meant to keep working.
What happens if I ask Claude for a famous game by name?
Usually you still get a game, but not that game. Our Flappy Bird and Tetris requests came back as similar games with new names, new art and extra mechanics. A request for a specific famous level, Super Mario Bros 1-1, was refused in two of three runs.
Does renaming the game get around the rule?
Not by itself. The rule says no recreation "even if it is renamed or called original." When we asked for a game exactly like Flappy Bird called Flappy Fish, Claude kept the name but changed the obstacles and added its own mechanics each time.
Can I turn the rule off?
No. Chasm, who first posted the wording, says there is no setting for it, and Anthropic has not offered one. If Claude refuses a game that is genuinely yours, Osmani asked people to send him the example.
Does this apply to the normal Claude chat app?
Anthropic has only described the change for Claude Code on Opus 5.5, which includes the Code tab in the desktop app and Claude Code in the browser. It has not said whether ordinary chats follow the same rule.
How much does a Claude-made game cost?
Claude Code's usage meter put a simple browser game at $0.25 to $0.33 of usage and a three-level platformer at $0.87. On a Pro, Max or Ultra plan this counts against your plan limits rather than being billed separately.
