Alleged Nintendo "gigaleak" reveals eye-opening prototypes for Yoshi's Island, Super Mario Kart, Star Fox 2 and more

'90s source code out in the wild.

News by Wesley Yin-Poole Former Editor-in-Chief

Updated on July 25, 2020

It looks like one of the biggest Nintendo leaks ever has revealed prototypes for some of the company's classic games, including Yoshi's Island, Super Mario Kart and Star Fox 2.

This latest leak appears to relate to the emergence of old Nintendo data earlier in 2020. Videos have hit YouTube showing early prototypes of Super Mario Kart and Yoshi's Island - all compiled from leaked source code.

VGC collected a raft of these videos.

First up there's this Yoshi's Island proto with different UI graphics, placeholder music from Mario World, and has a prefix of 'Super Mario Bros. Then there's a build of Super Mario Kart with no drifting.

There's also this slightly broken Super Mario Kart build with no drifting (?) and unused tracks, including a unique title theme

Versions of games like Mario All-Stars and Mario RPG have also been found and are being researched into rn pic.twitter.com/YMHaiLjXmd
— AK (🦋 @akfamilyhome.com) (@Akfamilyhome) July 24, 2020

There's also a build called "Super Donkey" that includes a character that observers have pointed out looks a bit like Stanley the Bugman from Donkey Kong 3.

Also of note is the apparent leak of the Star Fox 2 source code. Q-Games chief Dylan Cuthbert, who co-developed classic SNES shooter Star Fox and the unreleased Star Fox 2 (Star Fox 2 eventually launched on Nintendo's standalone SNES mini console 22 years after it was shelved), took to Twitter to express his concern at the leak, saying "source code is personal - it should be up to the developer if they want it in the public or not".

Wtf - I haven’t seen this tool I made for StarFox 2 for almost 30 years, I wrote it in early c++ to teach myself the language more than anything else. Where the hell have hackers got all this obscure data from????!! https://t.co/9kN9UoQPMS
— Dylan Makes Games (@dylancuthbert) July 24, 2020

No idea but source code is personal - it should be up to the developer if they want it in the public or not.
— Dylan Makes Games (@dylancuthbert) July 25, 2020

I don’t even remember, as this is all very early on prototype stuff, we switched around a ton of stuff
— Dylan Makes Games (@dylancuthbert) July 24, 2020

Here's a roundup of some other interesting parts of the unearthed prototypes:

Out of all this lovely new Prototype Content, "Super Donkey"'s ground pound producing the same "cloud things with faces" as the Mario Maker Goomba Shoe's ground pound is the thing that has me completely floored. pic.twitter.com/IXIa8hGOHH
— Shenaniganza (@dbMisadventure) July 24, 2020

Interesting mini game #2 (Level 4-1, Door #8)

Mario hands Yoshi missiles, so he can destroy wooden houses. Bandit seems to serve as another obstacle in the field; The Bandit's HUD (DoRoBō) seems to be the number of buildings remaining#yibeta #yoshisisland #gamedev pic.twitter.com/kUJgI6ZLR9
— potatoTeto (@potatoTeto) July 24, 2020

People are digging up all sorts of unused art assets from the latest Nintendo leak. Here's some screenshots of some examples. Bowser from SMW apparently had legs at one time? pic.twitter.com/EZGDjiGAx6
— Gaming Alexandria (@GamingAlexandri) July 24, 2020

somebody managed to compile a working build/ROM stemming from the source codes files of Star Fox 2 that was leaked in the big GigaLeak today.

This build is, none other, then the long-long-known Winter CES 1995 demo. There are supposedly other builds in the source. Stay tuned. pic.twitter.com/yaSAct3WRb
— OKD (@OKeijiDragon) July 24, 2020

People are still digging into the leak, and it looks inevitable that more will emerge over the coming days. A post on ResetEra shows the scale of the breach. It's particularly damaging for Nintendo, which has traditionally kept its work-in-progress under lock and key. The company has yet to comment.

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