There has been an alleged leak of early source code from some of Nintendo's biggest franchises - including one of the most-played video games on the planet, 'Super Mario 64'.

'Super Mario 64' was released in breathtaking style on Nintendo's first foray into 3D gameplay, back in 1996. Fast-forward nearly two and a half decades later, and here we are still talking about it.

The reason the game has been taking over the spotlight this week however, is due to a leak of Nintendo's games and what is said to be the original source code used in early developments of some of their most recognisable video games. Long-kept secrets have been outed of the likes of 'The Legend of Zelda: Ocarina of Time', 'Super Mario World 2: Yoshi's Island', and 'Super Mario Kart' for the first time, and 'Super Mario 64' is among the line-up.

According to VGC, early versions of the Nintendo 64 gem is said to have included Mario's often sidelined brother Luigi as also becoming a playable character in the platformer. Apparently an early version of the video game was titled 'Ultra 64 Mario Brothers' and included references to Mario's taller, greener brother.

Modders have now taken these files and have dumped Luigi into the world of 'Super Mario 64' for fans to see what the game might have looked like. Here are some tweets showing off what might have been.

Whether Luigi joined his brother for his first 3D adventure or not, he has managed to carve out his own series of video game classics in recent years. As well as having his own video game series with 'Luigi's Mansion', he also got his own 'Mario Bros' spin-off on the Wii U and Nintendo Switch with 'New Super Luigi U'. He's also appeared alongside Mario, Peach, Toad and the rest of the Nintendo world in all of the spin-off series, including 'Super Mario 3D World' and Ubisoft's 'Mario + Rabbids Kingdom Battle'.