Claude Fable 5 Rebuilds a 1993 Amiga Game in Godot

Summary

A developer describes using Claude Fable 5 through Claude Code to port Babylonian Twins, a game he wrote in Baghdad in 1993 for the Amiga 500, to Godot. The project had three increasingly difficult goals: move a 34,000-line 2010 C++ version to Godot 4, rebuild the original 72,758 lines of 68000 assembly at the Amiga's 50 Hz update rate, and embed that retro version inside the modern game. Claude Code could inspect the filesystem, edit files, run vasm, boot builds in FS-UAE, launch the game, and consume command-line probes and screenshots. It reconstructed the original toolchain despite missing long filenames, a truncated level source, and differences between ASM-One and vasm; the rebuilt binaries matched shipped bytes except for 108 bytes in variables that the author says may reflect a runtime memory snapshot, a conclusion he has not independently verified. The model recovered undocumented level, tile, object, door, sprite, and copper-list formats from the routines that read them. It rendered all five levels and achieved zero differing pixels against reference captures after accounting for the Amiga's sky gradient and water-color effects. The work also exposed errors in the port, including an overly broad guard attack range, incorrectly rendered hidden layers, doubled trampoline movement, malformed door-key data, and incorrect sound lengths. Human testing remained necessary for feel, historical intent, image review, release approval, and ambiguous design choices; the author also found a missing tutorial instruction through an old one-star review. The original disk image is free, the Definitive Edition is available on iOS and Android, and its Steam release is planned for fall with the 1993 version included.