The main challenge with the Nintendo 64 BIOS is its copyright and legal status. The BIOS is intellectual property owned by Nintendo, and its distribution is tightly controlled.
was created by the "Super Mario 64 Beta Archive" that allowed for saving data directly to the console instead of the cartridge.
: Distributing or downloading the BIOS without permission from Nintendo can infringe on their copyrights. This has led to a grey area where many emulators come without the BIOS pre-installed, requiring users to provide their own.