The file is compressed in a RAR archive, which is common for unofficial downloads found on third-party forums or file-sharing sites. Where to Get It Safely
The file you're referring to, is likely a pirated or unofficial distribution of DLC Set 1 for the shoot-'em-up game R-Type Final 2 on the Nintendo Switch . The file is compressed in a RAR archive,
– A reimagined stage based on content from R-Type Delta . File Technical Details The file is compressed in a RAR archive,
This is a Nintendo Submission Package file format, typically used for digital games and DLC on the Switch. The file is compressed in a RAR archive,
– A reimagined stage originally from R-Type III: The Third Lightning .