Maze War (Steve Colley, Howard Palmer, Greg Thompson)
Probably the first first-person shooter, Maze War put players in a vector wireframe, 3D grid they could navigate one step at a time. If you spotted another player you could shoot them. While Spasim may have a credible claim to being the first first-person shooter, it’s clear that Maze War is closer to what eventually became the genre. This truly is the very essence of the FPS. Over numerous iterations it was also so far ahead of its time in terms of what we would now consider staple genre features networked multiplayer, a level editor, mod support, and a spectator mode - that it’s easy to suspect some sort of sorcery at work. It would not be at all unreasonable to argue Maze War is the most important and influential video game of all time.