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.
Don Daglow
Don Daglow (born circa 1953) is an American computer game and video game designer, programmer and producer. He is best known for being the creator of early games from several different genres, including pioneering simulation game "Utopia" for Intellivision in 1981, role-playing game "Dungeon" in 1975, sports games including the first interactive computer baseball game "Baseball" in 1971, and the first graphical MMORPG, "Neverwinter Nights" in 1991. He founded long-standing game developer Stormfront Studios in 1988.