In 1990, a group of programmers moonlighting at Softdisk in Shreveport, Louisiana replicated the first level of Super Mario Bros. 3 on a PC using John Carmack’s adaptive tile refresh trick, sent it to Nintendo, and were politely rejected. That rejection birthed id Software. This episode follows John Carmack, John Romero, Tom Hall and Adrian Carmack from borrowed company computers and Scott Miller’s fake fan letters to Commander Keen, the shareware model that bypassed retail gatekeepers, and the founding of id in February 1991.

We break down the raycasting behind Wolfenstein 3D, the censorship that swapped blood for sweat and dogs for rats on the Super Nintendo, and the global phenomenon of Doom, which was installed on more computers than Windows 95. We look at the Columbine backlash and what Harvard, Secret Service and Department of Education research actually found, Quake’s client-server architecture and Trent Reznor soundtrack, Carmack’s open-source engine releases under the GPL, and the fractures that drove out Hall, Romero, Adrian Carmack and finally John Carmack in 2013. The story ends with ZeniMax, Microsoft’s $7.5 billion acquisition, the Doom Eternal soundtrack dispute between Marty Stratton and Mick Gordon, and recent layoffs of roughly half the studio.

• How Scott Miller’s identical return addresses gave away his recruiting scheme
• Shareware as a way around boxes, distributors and conservative publishers
• Raycasting versus true 3D and why Quake finally let players look up
• Why releasing engine source code under the GPL cemented id’s legacy
• The Ship of Theseus question facing a studio with none of its founders left