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 anonymously, it’s hard to definitively say what happened. However, 2020 has seen a number of Nintendo-related source code leaks, mostly about older Pokémon games. The running theory, MrCheeze says, is that it all hails from the same specific information breach, but we don’t know for sure. “We can only speculate,” he says.

So, what have people found?

The sheer amount of information coming out of the aptly-named “Gigaleak” is hard to keep track of. But some of the most interesting findings have to do with unused models, sprites, levels, and more.

Apparently, for example, Super Mario World contains assets where it appears Luigi gives the player the middle finger.

There are also a number of never-before-seen characters, like this mustachioed Yoshi.

We’ve got further confirmation that Mario is absolutely punching the hell out of Yoshi to elongate his tongue, too.

For Super Mario 64, folks are showing off early levels, like a castle one, where Nintendo likely tested Mario’s capabilities.

There are also early 3D models of iconic characters, like Link.

We may now also know what earliest rooms that Nintendo built for Ocarina of Time actually look like.

Apparently, at one point a scrapped Zelda game contained blood.

Folks are unearthing high-quality screenshots and assets that show classic games in more detail than we’ve ever seen before.

The Gigaleak also contains even more Pokémon sprites, like early versions of existing monsters and unused ideas.

Why is it controversial?

While fans are ecstatic to learn more about their favorite games, there are a few sticking points that people should be aware of. It seems likely that someone, at some point, broke the law — this is all proprietary information, after all.

But on a more humane level, none of this stuff was ever meant to be seen. Imagine, if you will, that you are a creator of some sort. Let’s say a writer. And one day you log on, and all of your unpolished janky drafts and ideas get published to the internet. That would suck, right — losing control over your own work?

Pushing this further into a morally dubious area is that the Gigaleak apparently contains personal information, including a diary and calendar, along with private conversations between developers. One file, for instance, recounts a traumatic childhood experience involving Mr. Potato Head.

Given the type of information contained in the leak, along with its questionable provenance, some are wary of what’s floating around, even if it’s gone viral. A couple of game developers and commentators fear that the video game industry will become more secretive than it already is to avoid leaks like this in the future.

Despite these worries, the so-called Gigaleak is already all over the internet and is only growing larger as fans continue to swim though the countless files contained within.

Correction: An earlier version of this article included a Super Mario 64 sound file that is a fan-made restoration, and not a park of the leak.