Johan Bové
Just waited about 5 minutes for the ZX-81 "3D Defender" game to load from the emulated "cassette" and played a more than 40 year old game awkwardly in my browser. https://archive.org/details/3D_Defender_19xx_J.K._Greye_Software
The "3D Monster Maze" wiki page explains how they wrote games in those days: https:// en.wikipedia.org/ wiki/ 3D_Monster_Maze
Absolute bonkers.
Johan Bové, Aug 12 2021 on social.johanbove.info