A file acts as an installation package for the 3DS, similar to an .exe or .msi file on Windows.
: 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
Originally released on , in Europe, this version was a retail physical title published by NIS America. Unlike the standard eShop "Cave Story" (which is a 2D port), Cave Story 3D features: A file acts as an installation package for