There were no changes to graphics, sound, or character/vehicle balancing in this specific version. Update History Context Preceding Version:

A file format (Nintendo Submission Package) used to install software or updates on a Switch console.

This implies that you have a .rar file containing an NSP file for "Mario Kart 8 Deluxe" on the Nintendo Switch, specifically an updated version (possibly 3.03), and that the file has been verified to work correctly. However, ensure you're obtaining and using files like these in accordance with Nintendo's terms of service and copyright laws.

The precise phrase represents a specific string of search keywords commonly used within the Nintendo Switch homebrew, emulation, and modding communities. This string translates technically to a search for a verified, compressed archive (.rar) containing the Version 3.0.3 software update in NSP or CH (Nintendo Submission Package / Update) format for the hit racing game, Mario Kart 8 Deluxe .