This is the standard format used by the Nintendo Switch for digital software. It is essentially a "dump" of the eShop version of the game.
Files distributed in .rar format on third-party sites are unofficial. Always verify the hash or source to ensure the file hasn't been tampered with. Mario Kart 8 Deluxe (NSP)(Update 2.1.0).rar
To see the Wave 2 tracks, a separate DLC NSP (the Booster Course Pass) usually needs to be installed alongside this update. ⚠️ Important Considerations This is the standard format used by the
Significantly shortened the time it takes for item boxes to reappear after being taken. Mario Kart 8 Deluxe (NSP)(Update 2.1.0).rar