>first LAN-based multiplayer 3D first-person shooter
that would be https://en.wikipedia.org/wiki/Maze_(1973_video_game), its right there on this site https://ultimatehistoryvideogames.jimdofree.com/maze-war
that would be https://en.wikipedia.org/wiki/Maze_(1973_video_game), its right there on this site https://ultimatehistoryvideogames.jimdofree.com/maze-war
I actually played multiplayer Maze War at the Living Computer Museum on a Xerox Alto in 2017: https://photos.app.goo.gl/VUVXQ1cG3zWAMWY3A Right is a real Alto and the other two are emulated. The three were running a multiplayer game.