Betrayal at Krondor

<h1 align="center"> <img src="https://github.com/user-attachments/assets/017732ab-3e84-4ee1-9780-3a3c0f831588" width="600" alt="Betrayal at Krondor"> </h1> <p align="center">A byte-perfect recompilation of the 1993 classic <em>Betrayal at Krondor</em>.</p>

About

This is a reconstruction of the original Betrayal at Krondor source, recovered by reverse-engineering the DOS binaries. It reaches a full byte-match with the original, reproducing the shipped binaries exactly. We even wind the computer's clock back to June 16, 1993 during linking!

No shortcuts were taken: any assembly in this project exists because the original was written in assembly too.

The goals are educational: digital archaeology and preservation. It won't add support for modern systems or mod the game. I plan to do that in a separate fork.

Supported releases

The following releases build byte-identically from this one tree:

• 1.00 (floppy, June 16, 1993) — c943fd895a57
• 1.02 (CD-ROM, March 21, 1994) — e254770143e0

Asset viewer

Reverse-engineering the code is half the work (okay, maybe more). Betrayal at Krondor is a big game, with lots of assets and a branching, data-driven dialogue system. To explore all that, this project includes a browser-based asset viewer:

<img width="828" height="420" alt="viewer" src="https://github.com/user-attachments/assets/84f9ce3e-ddc7-4ff2-9914-03e2fb59853a" />

Drop your own game files into viewer/data/ and run uv run bak viewer, then open the printed URL.

Building the project

See BUILDING

Contributing

The project has achieved a full byte-match, but it isn't finished: the code still carries decompilation artifacts, baked-in constants, and wrong names. What's left is human work: reading each function until you understand it, then naming and documenting it truthfully, without breaking the byte-match.

PRs that improve code quality are welcome. Start with CONTRIBUTING, then pick an unclaimed module from the status list. See ACTORREC.C and ACTORREC.H for examples of clean modules.

Acknowledgements

This reconstruction builds on earlier reverse-engineering of Betrayal at Krondor:

• Guido de Jong, for xbak
• Emmanuel Jacyna, for BaKGL

License & legal status

The original work in this repository is released under the MIT License (see LICENSE).

This project does not grant, and cannot grant, any rights to third-party material:

• Betrayal at Krondor, its code, data, and assets are copyright © 1993 Dynamix, Inc. / Sierra On-Line. The reconstructed C source under bak/SRC/ is a reverse-engineered derivative of that copyrighted program, provided for research, preservation, and interoperability study. This repository contains no original game data files; to build a runnable binary or to use the viewer you must supply your own legally-obtained copy of the game.

This is an independent preservation effort and is not affiliated with or endorsed by Dynamix, Sierra, or their successors.