Doom (1993 video game)
The ability for others to create custom levels and otherwise modify the game using WAD files turned out to be a popular aspect of "Doom". Gaining the first large mod-making community, "Doom" affected the culture surrounding first-person shooters, and also the industry. Several future professional game designers started their careers making "Doom" WADs as a hobby, among them Tim Willits, who later became the lead designer at id Software.
Doom (2016 video game)
At Electronic Entertainment Expo 2018 press conference, on June 10, Bethesda Softworks announced a sequel named "Doom Eternal" is in the works; gameplay footage was showcased at Quakecon 2018. It's based on idTech 7 and was confirmed to come to the PC, PS4, Xbox One, and Nintendo Switch.