A Massive Leak of Nintendo Source Code Is Causing Chaos in Video Games

The leak unearthed new revelations about classic games like 'Super Mario 64,' and caused a split amongst preservationists about what to do with likely stolen material.
July 28, 2020, 1:00pm
A piece of art from the Nintendo video game Super Mario Galaxy.
Artwork courtesy of Nintendo

The gigaleak. That’s the name retro enthusiast and amateur game developer Cosmo came up with when they realized the trove of secrets that had leaked out of Nintendo last week, which have dominated gaming’s attention ever since. Source code for games like F-Zero and Link to the Past. A full development history of Pokémon Diamond and Pearl. Prototypes for Super Mario Kart and Yoshi’s Island, which Nintendo called Super Mario Bros. 5: Yoshi’s Island at some point. A cache of emails from Argonaut Software, co-developers of Star Fox.


It’s a massive and historically unprecedented look at the creative process of a company that, like Apple, prides itself on secrecy. It was also most likely stolen, and thus represents an invasion of privacy that has fans and preservationists confused on how to view the material.

Nintendo did not respond to a request for comment by VICE Games.

On Friday afternoon, an anonymous 4chan user posted a link to several files hosted on anonfiles, a service for people to share material without fear it’ll get linked back to them. Even in the rough and tumble world of 4chan, people were hesitant to see what they were.

“im not clicking those,” wrote one user.

It became a game of chicken before, inevitably, someone downloaded the files and realized they were sitting on something far more than a virus. Around this same time, a community of enthusiasts who specialize in dissecting rare gaming material became aware of what had happened, thanks to bots they programmed to scrape places like 4chan. That group who asked to keep their name a secret because of Nintendo’s frequent history of issuing lawsuits.

The term “gigaleak” came to Cosmo on a whim and it stuck.

“If you're first you get the recognition and I was first,” said Cosmo in a private message on Discord over the weekend.

That’s when everything exploded: Twitter, Reddit, the group Cosmo is a part of. It was everywhere. On a Discord channel, I watched in real-time as hundreds of fans picked apart the files, trying to sort what was new, what was old, and what would send fans into a tizzy. The phrase “holy shit” was uttered often enough that it eventually became meaningless.


Every few minutes, people would find something revelatory, like the word “fuck” snuck into the source code of Link to the Past, or confirmation that Luigi was, in fact, meant to be part of Super Mario 64. Especially striking was realizing the evolution of Yoshi’s character design:

These discoveries have continued, as have the leaks, suggesting there’s more to come.

Where the “gigaleak” came from, however, remains a mystery. But there are some clues.

There have been two major breaches of Nintendo security in recent years. On January 31 of this year, hacker Ryan “RyanRocks” Hernandez pleaded guilty to hacking Nintendo’s servers and possession of child pornography. The FBI reported Hernandez, who released a Switch design before it was announced, had “thousands of confidential Nintendo files,” but it has never been made public what Hernandez had access to and how widely he’d shared it.

The other intrusion happened in 2018 by Zammis Clark, who went by a number of pseudonyms online, including Slipstream, Raylee, and wack0. (Among the video game community, he was more commonly known by wack0.) According to The Verge, the former security researcher first managed to infiltrate Microsoft’s servers and steal roughly 43,000 files, which included early versions of Windows, code names for unannounced and unreleased products, and in-development versions of various software. When Clark was caught, he was released on bail, and soon after hacked Nintendo’s servers, gaining access to “highly confidential game development servers” with “code for unreleased games.”


Nintendo wasn’t aware of the breach for months. Clark successfully infiltrated Nintendo’s private network in March 2018, but didn’t become aware of what happened until May. As with Hernandez, it’s never become public what exactly Clark was able to get from Nintendo.

The original 4chan post that kicked off the gigaleak was titled “ppg leak time: fuck ganix.” The post was published on 4chan board /vp/, which is specifically dedicated to Pokémon. It sounds like shitposting gibberish, but in reality, it might help reveal what’s happening here, because there’s an alleged connection between one Nintendo hacker and an older leak.

One of the most important Nintendo leaks in the last several years happened in May 2018, when a version of Pokémon Gold and Silver, shown publicly at Nintendo’s former Space World trade show in 1997, appeared. This version was interesting to the Pokémon community because that trade show version was much different than what shipped in 1999.

The file was randomly distributed to a Discord server, according to Game Informer, by a user calling themselves “__.”

In December 2019, a prominent Pokémon leaker known as Ganix, known for releasing early versions of various Pokémon creatures, released a confessional letter on the message board for Glitch City Laboratories, a community dedicated to dissecting Pokémon games. Ganix alleged to have worked with the user __, who they claimed was another pseudonym for wack0, aka Zammis Clark.


“There were many Pokémon-related things that [Clark] had come into possession of, including tools used to make the games, development versions of the games, and even source code for the games,” said Ganix in the post. “He entrusted some of what he had with certain individuals, whether that be knowledge, tools, or data. [..] I was one of those people he entrusted things with.”

Ganix went on to admit to leaking all sorts of other Pokémon-related material based on access to unfinished copies of games, though it’s unclear if the material they were releasing was in continued collaboration with Clark. The goal of distributing the early Pokémon artwork was “to give people a glimpse of ‘what could have been.”

Attempts to contact Ganix by VICE Games were unsuccessful, as of this writing.

Glitch City Laboratories became collateral damage in this process; the site’s administrators recently announced it would revert its extensive and detailed wiki to a state prior to the release of various Pokémon source codes. The message boards will also shut down. As we reported back in May, shortly after another leak of Nintendo source code, this kind of material is highly valuable to fans who hunt for weird glitches or emulator makers, but using code that might have been illegally obtained is a huge liability.

Ganix did grant an interview with Pokémon historian Dr. Lava in December 2019. The interview noted that following the leak, Ganix had been doxed by toxic Pokémon fans on 4chan motivated to discover the person behind the leak, figuring they had access to more and were holding out.


“Various tribes in the proto [prototype] Pokémon community have basically been at war with each other since the first leak happened in May 2018,” said 4chan user Phoebe to VICE Games, who has watched these events unfold over the last few years. “That's when folks realized there was a lot more in private hands, and they were pissed they were left out.”

Like many anonymous leaks, it’s hard to say with absolute certainty what happened. At this point, we don't know if Ganix had access to the materials in the gigaleak, if it was related to previously reported hacks of Nintendo, or something else entirely.

In some respects, where it came from is irrelevant; it’s already out there. It’s been written up extensively in the games press, and has absolutely flooded social media and YouTube.

“Source code represents hours, days, months and years of hard work, and blood, sweat and tears, and is very personal to every developer,” said Q-Games founder Dylan Cuthbert, who was a programmer at Argonaut during the making of Star Fox. “So it feels very intrusive to suddenly have random ppl [sic] on Twitter asking me or others to explain the context of every off the cuff comment in the code, at its best it is ridiculous and at its worst it’s insulting.”

Internal emails from Argonaut, which include references to arguments over porn being distributed around the office, were part of the leak. And while Cuthbert condemned the leak to VICE Games, he couldn’t help but talk about the parts that fascinated him on Twitter:

“Most companies are terrible at preserving their games, and piracy and other means have salvaged or saved many games,” said a developer who specializes in preserving game history, who asked to remain anonymous to avoid disrupting any potential business deals with Nintendo. “Based on this breach, Nintendo is much better than most at archiving. But that's why invasive data theft of this magnitude, while an anomaly, shouldn't be encouraged.”

Nintendo has a long history of responding to its most intense fans with legal threats, and has been one of the most active and aggressive video game companies in having ROMs (digital copies of old games) removed from the Internet, even if there’s no way to legally purchase those games anymore. Similar to the rest of the industry, it also shuts down services that with crucial parts of gaming history, preventing future players from ever gaining access.


The reaction from the preservationist community has been, weirdly, a lot of silence.

The Video Game History Foundation declined to comment, and its Twitter account, which regularly links to behind-the-scenes bits about old games, hasn’t referenced anything from the leak so far. The Strong Museum History of Play in New York, which has a whole section dedicated to video games, did not respond to my request for comment, as of this writing.

The Internet Archive was briefly hosting parts of the leak. The organization declined to specifically comment at first, and pointed me towards its policy on copyright, where it reserves the right to take down material “that appears to infringe the copyright or other intellectual property rights of others.” Not long after, the organization pointed me back towards the page it was being hosted, and the files were now gone.

When asked if Nintendo specifically asked the files be taken down, Internet Archive director Mark Graham told VICE Games said he wasn’t aware of any such request.

Do you have any insight into this leak? Using a non-work phone or computer, you can contact Patrick Klepek securely on Signal on 224-707-1561, or email patrick.klepek@vice.com.

So far, it appears Nintendo has not issued cease-and-desist notices to any articles about the leaks, nor issued takedown notices to YouTube videos featuring the material. It also has not asked Twitter or other social media platforms to take down any related images or tweets.

“This is, to my knowledge, the biggest leak of development info for a major publisher to date,” said former games journalist Jeremy Parish, perhaps best known as co-host of the popular retro gaming podcast Retronauts.


Parish recently joined Limited Run Games, the publisher that specializes in shipping physical versions of games in an increasingly digital world, as a media curator, focused on writing and talking about the games they’re publishing. It’s the equivalent of an in-house historian.

“Nintendo has been locked tight for as long as I've been covering them,” said Parish. “They're the gatekeepers of their own history. They share very little, and always on their own terms. And that's their prerogative, and this isn't going to move the needle in any direction… mainly because it would be difficult for Nintendo to be less open about their development processes.”

Parish called the leak “awful,” echoing a sentiment from others in the preservationist community I spoke to, even those drawn to what it tells us about Nintendo. It’s a raw dump, which has the advantage of not being filtered but also means it’s being taken out of context.

“I wish developers and publishers would work more closely with archivists to document their history,” said Parish. “Not just Nintendo—everyone.The kind of exhaustive documentation that's been devoted, by creators themselves, to the likes of the Star Wars franchise or the Beatles catalog doesn't really exist in gaming, and that's down to the compulsive secrecy of publishers.”

The video game industry regularly keeps irrational secrets. Nintendo just happens to be more secretive than most, and they also happen to be one of the most beloved creators. It’s the combination that makes this leak, more than others, stand out. It’s truly unprecedented.

“I'm not saying leaks like this are on publishers' own heads,” said Parish, “but…if they would work more closely with writers and historians who work in good faith to document history, leaks like this would seem less momentous.”

Follow Patrick on Twitter. His email is patrick.klepek@vice.com, and available privately on Signal (224-707-1561).