In honour of the 25th anniversary of Commander Keen, co-founder of id Software John Romero - better known as the guy behind first-person shooters (FPS) such as Wolfenstein 3D, Doom, and Quake - tweeted on Monday night a video of demo gameplay of Super Mario Bros 3 (SMB3) running as a port on the PC.
Okay don't get your hopes up, the development was back in September 1990. Also, if you're wondering how the two - Commander Keen and Super Mario Bros - are connected, read on.
Unfortunately for 90s' computer users, Nintendo was more interested in developing games for its own hardware. The Japanese giant turned down a Super Mario Bros 3 PC port proposal from id Software - then called Ideas From the Deep (IFD) - and hence Romero & Co. made their own game called Commander Keen, a side-scrolling platformer inspired by the world of Mario.
The SMB3 demo was designed as a pitch to Nintendo, and hence is only a prototype. It doesn't look the finished product, what with missing background music and altered sound effects, plus the weird jumping that can be seen in the video.
But as US reports, they were not only working on an inferior system with limited capabilities back then - in the PC against the then-mighty NES - but also "had no access to the original physics or assets, so the fact they even got that close is nothing short of awe-inspiring".
Since 1990, id Software has come to be recognised as one of the most important studios especially in the arena of computer graphics technology and game engines.
Commander Keen may have been the game to kick-start the company co-founded by Romero, but it would be Wolfenstein that would catapult them into prominence, being the first FPS with unprecedented 3D graphics. They followed it up with Doom that brought the genre to the mainstream and then Quake introduced online multiplayer to the world.
Catch the latest from the Consumer Electronics Show on Gadgets 360, at our CES 2026 hub.