Zeliard Source Code and Reverse Engineering
This project reconstructs the 1990 DOS release of Zeliard at the source level and provides a complete, start-to-finish playable browser port.
A complete preservation project
Bit-perfect Zeliard source reconstruction
The canonical source tree targets MASM 5.1 and rebuilds the DOS loader, game engine, graphics and input drivers, town and cavern systems, enemy AI, bosses, cinematics, and resource archives. Release output is compared byte-for-byte with the original game. Instrumented debug builds provide a behavior oracle without changing the canonical release artifacts.
C and WebAssembly reimplementation
The browser edition is a native reimplementation, not an emulator-hosted release. A portable C engine implements the game while the TypeScript shell supplies browser display, audio, keyboard and gamepad input, compatible .USR saves, and deployment. The original MASM behavior and reconstructed bytes remain the authority for compatibility decisions.
Reverse-engineering tools and research
The repository includes SAR extraction and decompression tools, GRP image decoding, save-file utilities, symbol and data audits, function-level behavior probes, deterministic replay fixtures, and visual parity artifacts. The project is useful both as playable game preservation and as a detailed example of reverse engineering a segmented 16-bit DOS game into a modern portable runtime.