Massive Nintendo leak reveals early Mario, Zelda, and Pokémon secrets

In late July, anonymous users on internet bulletin board 4chan started posting files purporting to show source code and development repositories of over a dozen classic Nintendo games, from Super Mario World and a canceled Zelda 2 remake to Super Mario 64 and The Legend of Zelda: Ocarina of Time. Since then, fans have pored over the files and are flooding social media with all sorts of previously unreleased information, some from games we know and love, and some hailing from early builds of those games. Here’s what you need to know.

What’s in the leak?

Tons, much of it distributed in two big chunks — one for Super NES games and another for Nintendo 64 games. But in terms of what might interest an average person, the leak appears to contain source code for Super Mario Kart, The Legend of Zelda: A Link to the Past, and Yoshi’s Island. What this means is that people can look at the original code that makes up these games; normally, these are the sorts of files that the public can’t access and never gets to see, because what’s playable is very different than what developers use to build games.

How do we know it’s real?

Reached for comment, Nintendo did not respond in time for press. However, according to two well-known Nintendo data miners, the volume of data released points to the code being legitimate.

“Folks presume it’s real because the sheer magnitude of files, things like secret IDs that are impossible to crack,” says Orcastraw, a speedrunner who has been sharing notable finds from the leak.

“Faking it would be as hard,” says MrCheeze, a well-known Nintendo hacker. Making it up would require someone to create “all these games from scratch,” he adds. That would mean coming up with thousands of files, something that would be nearly impossible.

But perhaps the most compelling reason to believe it’s true is that at least one former Nintendo worker has corroborated pieces of the leak.

Dylan Cuthbert, lead developer on four Star Fox titles, reposted a screenshot of the leak that shows a tool he made nearly 30 years ago for Star Fox 2. “Where the hell have hackers got all this obscure data from????!!” he wrote.

How were these files obtained?

Since they were uploaded…