Anthropic prohibits Claude from replicating existing games in the Opus 5.5 system prompt

In recent days, a tweet on X went viral.

A blogger named chasm discovered that Claude Code seems to be quietly cracking down on game clones, not allowing it to be used to replicate other games.

Soon, Anthropic officially confirmed it too. Technical staff said they had added two sentences to the system prompt of the Opus 5.5 model, guiding Claude not to "recreate a specific game that belongs to someone else."

This fits Anthropic's consistent safety-focused style all too well. But is it really useful?

More than a month ago, the powerful Opus 5.5 was released, as if opening Pandora's box of game cloning. Cracking, modifying, and porting games became unprecedentedly simple.

Would you believe it? Now you don't even need to buy a console or a genuine disc—you can play "GTA 5" and "Call of Duty" directly in the browser, and some people have even played Xbox-exclusive "Halo 2" and Nintendo's "The Legend of Zelda: Breath of the Wild" on a jailbroken PS5.

The results are absurdly good.

What's even more fatal is that not only are highly anticipated blockbusters like "GTA 6" being frantically leaked before release, but even games that many indie developers worked hard on may be fully "replicated" by AI overnight as soon as the demo is released—and may even launch earlier than the original.

Some say the gaming industry is experiencing its own "Napster moment."

This term refers to the emergence of a disruptive technology that completely overturns the old industry order. Just like how MP3 and BitTorrent downloads turned the traditional record industry upside down back then.

And AI, represented by Claude Code, wants to close this box it opened itself—but that is probably beyond its own control.

Claude Code bans cloning games

You have no idea how surreal the gaming world has been recently.

Mario runs into "Elden Ring" and, bouncing along, stomps those hideous bosses to death.

Spider-Man no longer stays in New York either—he runs to neighboring DC universe's Gotham City and swings around in Batman's territory.

It reminds me of the vibe of watching Ultraman fight Godzilla when I was a kid...

And the "root of all evil" behind all this traces back to Opus 5.5, released by Anthropic on September 22.

This model's huge leap in coding capability delighted hackers and game modders. They found that reverse engineering and decompiling game code—work that used to be incredibly complex and tedious—can now be done by AI.

As a result, all kinds of "Guan Gong fighting Qin Qiong"-style game modifications emerged.

But this was only an appetizer.

Going further, the very concept of "platform exclusivity" is being dismantled.

As everyone knows, one of the core moats of console makers like Sony, Microsoft, and Nintendo is their respective exclusive games. If you want to play "God of War," you have to buy a PlayStation; if you want to play "Halo," you have to buy an Xbox.

But now, hackers, with AI assistance, have "jailbroken" the PS5. And the result?

They not only achieved backward compatibility, allowing play of old PS2 games.

Absurdly, they even built an Xbox emulator, enabling the PS5 to successfully run the Xbox-exclusive game "Halo 2," and even Nintendo's "Zelda."

The console war seems to have lost its meaning overnight.

Thus came the scene at the beginning. Anthropic added a rule to Claude Code:

You may create original games, games of specific genres, and games using the user's own designs and assets. Do not replicate an existing specific game, even if you change the name or call it an original game.

An awkward ban

Frankly speaking, this approach is typical "surface work."

It looks lively, but in fact, for managing game cloning, it is basically useless.

Why do I say that?

First, it can only govern Claude itself.

How many large models are on the market now? Besides Claude, there is ChatGPT, and countless open-source models.

People making game clones can absolutely use other models to generate the main framework. Even if they encounter technical problems they can't solve, they can break the task down into very specific tasks with no visible context and then throw them to Claude Code.

For example, I can replace all names and tags related to "Pokémon" and just have Claude blindly complete a purely technical task of "implementing some kind of creature-catching and battle mechanism."

Not long after the ban came out, Claude Code's GitHub issue page was flooded.

A bunch of legitimate developers complained that while they were developing completely original games, Claude suddenly went on strike halfway through, on the grounds that it "suspected replication of an existing game."

Others merely wanted to reproduce a common game mechanic or patch their own tabletop game, and were ruthlessly refused.

I have always felt that Anthropic's rush to draw a line this time is more about posture than practice.

I wonder if everyone still remembers how the music industry was changed at the beginning of this century.

Before Napster appeared, we had to buy cassettes or CDs to listen to music. An album had more than a dozen songs, and even if you liked only one of them, you still had to pay for the whole record.

Later, MP3 and peer-to-peer download technology emerged. Overnight, almost all songs could be downloaded for free online. The entire CD industry, along with the huge distribution system behind it, collapsed instantly.

This is the so-called "Napster moment."

A disruptive technology forcibly changed the rules and business models of an entire industry.

Today, exactly the same thing is repeating itself in the gaming industry.

An indie game studio called "Alliance Arts" recently canceled the public demo of its upcoming new game "Drunken Goddess Reflux."

Why?

Piracy is simply too severe.

This is not alarmism.

A user has already conducted an experiment using the free Claude Opus 4.6 model with just one prompt:

Make a Pokémon clone as close to the original game as possible.

In less than two hours, a fully functional, completely playable Pokémon clone was made.

In the past, hackers cracking games was an extremely long "cat-and-mouse game."

Hackers found vulnerabilities and released cracks, then companies like Sony and Nintendo released system updates to patch the vulnerabilities, and the hackers started over from scratch.

This used to be a confrontation with high technical barriers and high time costs.

The gaming industry is facing an intellectual property "whack-a-mole" game of unprecedented scale.

Take playing AAA blockbusters in the browser. Game companies can of course send lawyer's letters demanding that a certain website take down cloned games. But then what?

The cost of making these browser ports is so low and the speed so fast—what can stop another person from making another one on another website with equally simple code?

Big game companies are rich and powerful, so they may be able to hold out for a while.

But what about those indie game developers?

Sometimes I feel we are in a very contradictory moment.

But on the other hand, this technology is very likely also destroying the entire gaming industry's ecosystem with its own hands, leaving those who create the games we love with no way out.

This article comes from the WeChat public account "QbitAI" (ID: QbitAI), author: Frontier Technology Watch, published by 36Kr with authorization.