ZZT is an ancient game creation system for DOS written by Tim Sweeney. To play ZZT games, you'll need to download ZZT 3.2. You'll probably also need a DOS emulator to run ZZT. Try DOSBox.
A space action adventure game for ZZT
A space action adventure game for ZZT
A powerful editor for ZZT worlds
A collection of ZZT and MegaZeux utilities for DOS
A time-travel action adventure game for ZZT
A tool to unlock ZZT worlds