The developer put two years into the project, spent as much as $2,000 a month and worked 10 to 14 hours a day. Now the AI that helped write the game won’t help anymore.
A Pokémon fan who posts on X as Big Kid Nation said Anthropic's Claude models are “starting to refuse” work on projects that use official Pokémon assets. The post went up last night with a screenshot attached. In it, Claude said it could no longer generate code intended to work with images it had detected as featuring official Pokémon designs.
“Anthropic has cracked down and Claude models are starting to refuse work on Pokémon fan projects,” Big Kid Nation wrote.
Thousands spent, nothing earned
Big Kid Nation’s frustration goes further than one refused request. They said the project never earned them any money, and noted that other fan creators do accept payments.
“All that money spent, never took a cent (unlike many others with itch.io, Patreon etc.),” Big Kid Nation wrote. “Nintendo. Just make the epic Pokémon game you know we all want. I’ll live on the street and work for free if it helps.”
That is a lot of emotion to point at a company whose characters they have been using without permission. Still, they clearly mean it.
The game itself
The project is titled “Pokémon Arena 2D.” The listing on BigKidNation.com describes it in three lines: “Real-time arena battles in pixel art. Two years in the making, and free to play.”
So far, The Pokémon Company’s lawyers have left it alone. A fan game that carries the brand’s name in its title and uses official designs probably won’t escape their notice for long, and Claude appears to have flagged the issue first.
Earlier this month, in another X post, Big Kid Nation said the project involved “$2,000 expenses a month and 10-14 hour days both learning and building for most of this year and last.”
Pushing back on the “slop” label
AI tools wrote the game’s code, and Big Kid Nation has argued with people who write it off as “AI slop.” Their defence is the effort involved. They said they left their PC on overnight to run simulated battles in Pokémon Arena 2D and find balance issues, then sat at the computer for 14 hours a day themselves.
They are also an enthusiast. “Vibe coding games is so fun,” Big Kid Nation wrote last month. “There are some negatives with unethical vibe coders. But you’re creative and love game development it’s just a dream. What took me a year to make people can make in a week. And some can’t make anything original. But those with ideas it’s just one thing after another.”
The “original” example
The point about originality ran into trouble once Big Kid Nation gave an example. They held up Poké Derby, a project made by other developers, as an “original vibe coded project.” It looks like a Pokémon-themed take on Umamusume, the popular Japanese racehorse game.
“This is what I’m talking about,” Big Kid Nation wrote. “Instead of seeing ideas and just taking them with no creativity, these guys just build their own unique world from scratch.”
Many replies noted that the game was a Pokémon-themed Umamusume. Big Kid Nation did not appear to be persuaded by any of them.
The next official entries in the series, Pokémon Winds and Waves, arrive next year as Nintendo Switch 2 exclusives. They won’t need Claude’s approval.