A pioneering 1993 first-person shooter that popularized fast-paced 3D action, modding, and shareware distribution, setting the template for the genre.
- Developer: id Software
- Genre: First-person shooter
- Platforms: MS-DOS (1993); countless later ports
- Mechanics: Run-and-gun combat, keycard-based progression, maze-like levels, secrets, moddable WAD files
- Notable: Massive cultural impact, influential level design and engine tech, foundational for FPS history