Disk Layout

Disk Layout

The game shipped on three 880 KB floppy disks. The layout is a hard constraint that corroborates how the tilesets are selected: the disk a level’s tileset lives on always matches the level’s own disk.

Disk 1 (GAMEDISK1:)	Disk 2 (GAMEDISK2:)	Disk 3 (GAMEDISK3:)
bcdfa, bcdfo	bcdfb, bcdfc, bcdfd	bcdff, bcdfg, bcdfh
bcdfp, bcdfq	bcdfe, bcdfm, bcdfn	bcdfi, bcdfj, bcdfk
bcdfr, bcdfs, bcdft	bcdfu, bcdfv, bcdfx	bcdfl, bcdfy, bcdfz
bcdfw (icon)	—	—
configuration.dat	—	—

Why the disk layout matters

The per-level monster stores (bcdfb–bcdfn) and the tilesets are opened by name from the decompressed bcdft image, using a patched "bcdf?" template. The two volume strings "GAMEDISK2:" and "GAMEDISK3:" also live in that decompressed image, and the level-entry routine PEAs whichever one the current level needs before opening its tileset.

Notice the pattern:

• GAMEDISK2 carries bcdfb–bcdfe, bcdfm, bcdfn (levels 1–4, 12, 13) and exactly one tileset, bcdfx.
• GAMEDISK3 carries bcdff–bcdfl (levels 5–11) and exactly two tilesets, bcdfy + bcdfz.

No level ever needs a tileset from the other disk.

ADF images

Three ADF images exist at data/blackcrypt/amiga/adf/, each 901,120 bytes (standard 880 KB DD). They have a valid Amiga OFS/FFS filesystem with the root block at sector 880.

bcdfw — the odd one out

bcdfw (457 B) starts with the bytes E3 10 00 01 — the standard AmigaOS DiskObject magic (0xE310) + version 1. It’s a Workbench drawer icon, not tileset data. The installer program InstallCrypt copies it to the destination during setup so the newly created game folder gets a custom Workbench icon. It is never opened by the running game.