I should verify technical specifics. Naomi Bios is a separate file, and Sega used different BIOS versions for different regions. The Dreamcast has its own BIOS, and the two are distinct. So the ZIP likely contains the correct BIOS files for either the Naomi or the Dreamcast, depending on the emulator's needs. Users might mistakenly refer to a combined BIOS file when it's actually separate.