: These files are typically installed using homebrew tools like FBI or GodMode9 .
: The 449MB size mentioned is standard for the European (EU) version of Cave Story 3D, which often includes additional language data compared to other regions. Cave Story 3D (EU) Release Details Download Cave Story 3D (EU) | CIA File | 449M
A file acts as an installation package for the 3DS, similar to an .exe or .msi file on Windows. : These files are typically installed using homebrew