iD Software was one of the pioneering studios in video game history, virtually inventing the modern 3D shooter with Wolfenstein 3D and later Doom. But before that, they attempted to land the job of porting Super Mario Bros 3 to the PC.
Nintendo had never actually asked anyone to port the beloved NES classic — then fairly new — to home computers, but iD figured if they made a functional port and showed it to Nintendo representatives, the company could be convinced to give the project their blessing. A new coding method had been created by one of the developers that allowed for scrolling in all directions, among other vital functions very few PC games had at the time. Nintendo turned down iD’s pitch, telling them they wished to keep Nintendo-developed titles on Nintendo platforms.
But John Romero kept the prototype, and a few days ago he uploaded a video of the entire thing! iD’s Super Mario Bros. 3 is far from the entire game — just one level has been completed, while only one world is accessible. The other levels after Level 1 are largely empty, save for blocks spelling out “LIKE IT?” in Level 2. Mario’s flying ability granted by the Magic Leaf is also heavily overpowered, allowing constant hovering through the rest of the area. But things like this would likely have been corrected had the project gone any further.
You can check out John’s playthrough of Super Mario Bros 3 PC — what exists of it — in the Vimeo video linked here.