: Stands for "Nintendo Submission Package." This is the standard file format used for Nintendo Switch digital content (e.g., games, DLCs, and updates) found on the eShop.
This is almost certainly a mod compilation , not an official Nintendo distribution. The “303” version number is a modder’s way of tricking the Switch OS into accepting the patch as newer than 3.0.1. mariokart8deluxeupdate303nsprar exclusive
Let’s start by dissecting the string piece by piece. : Stands for "Nintendo Submission Package
tracks, characters (Diddy Kong, Funky Kong, Pauline, Peachette), and the "Music" button. characters (Diddy Kong
: These tags often signify a specific repack, compression format (RAR), or a release from a particular source/group.