A strange little side quest
If Zombie Reborn sends you down a curiosity rabbit hole, start here. Doom changed game design and distribution in 1993 by separating its engine from content and spreading widely through shareware. A second detail makes the picture even better: Spacewar! appeared on MIT's PDP-1 in 1962 and became one of the earliest influential computer games shared among programmers. Grombi files that under: small game, surprisingly large backstory.