The .rar is a container; the internal .nsp is the standard digital format used for Nintendo Switch games and emulators.
The demo on the official Nintendo eShop is approximately 1 GB . If your .rar or extracted .nsp is significantly smaller (e.g., only a few MBs), it may be incomplete or malicious. Safety & Legitimacy Sea of Stars (NSP)(DEMO).rar
This file is typically used on Nintendo Switch consoles with custom firmware (CFW) using installers like Goldleaf or DBI . Note that the demo was officially released for free on the Nintendo eShop, which remains the only 100% safe method for acquisition. The .rar is a container
You can use tools like NSC_Builder (Nintendo Switch Cleaner and Builder) to verify the file's hash and digital signature against known legitimate copies. only a few MBs)