About
Bumpy's Arcade Fantasy is a 1992 DOS game by Loriciel, referenced here via its English-language release. This project is a structure-faithful decompilation of Bumpy's Arcade Fantasy: a C reconstruction of the original DOS engine that mirrors the original binary function-for-function and matches its control flow and data layout, grounded in a Ghidra disassembly of the game. It also includes pure-Python tools that decode the game's original asset formats into level images, sprite sheets, and world maps, plus reference documentation on the engine's internals and file formats. It builds two executables: a byte-compared reconstruction of the original that is never run, and a separate playable version with a thin platform layer added so the reconstructed engine can actually run. The original game's data files are copyrighted and are not distributed with the project — players must supply their own.
How it differs from the original
Unlike a typical clone, this project deliberately mirrors the original binary's internal structure rather than rewriting the game logic; the only new functionality added on top of the reconstructed engine is a thin host-platform layer needed to make it playable, kept separate from the non-runnable, byte-faithful executable build.
Getting started
Playing requires supplying your own copy of the original game's data files; from there, either the included Python tools can extract levels, sprites, and world maps as images, or the reconstructed engine can be compiled with the Open Watcom DOS toolchain into a playable executable and run under DOSBox.
History
The project began as a weekend AI-driven reverse-engineering challenge, deliberately choosing an obscure game with no prior reverse-engineering or reimplementation work; started with an early 'Claude Fable 5' model before it was banned, the work continued with Opus and ultimately took about a month of AI-driven effort steered by a human, in the process producing ad hoc emulators, validation scripts, and DOSBox-X patches along the way.
Additional notes
- Leftover artifacts
- Ad hoc tools built during the effort — including full emulators, validation scripts, and DOSBox-X patches — remain in the repository's git history but were not kept in the project's final file list.