Microsoft and Activision Open Source Classic Zork Games

Microsoft and Activision have collaborated to open source the classic text adventure games Zork I, II, and III. The move, announced on November 20, 2025, aims to preserve the historically significant code and make it available for educational and exploratory purposes under the MIT License.

A Pioneer in Interactive Storytelling

Zork revolutionized gaming by relying solely on text, challenging players with detailed descriptions and puzzles. The games ran on the Z-Machine, a virtual machine that enabled cross-platform compatibility.

Preserving Gaming History

The source code release includes Zork I, II, and III, along with documentation and clear licensing under the MIT License. This initiative contributes to existing historical repositories on GitHub, focusing on preserving the code without commercial packaging.

Running Zork Today

Enthusiasts can compile and run the games locally using tools like ZILF, a modern Z-Machine interpreter. The article provides detailed steps for compiling and playing the games, including CLI implementations in Python with a retro CRT filter.

Encouraging Contributions

Microsoft welcomes contributions to the source code, emphasizing preservation and education over modernization. Developers are encouraged to explore and learn from this foundational piece of gaming history.