Batman Arkham Knight -nsp--eshop-.rar -

Based on the filename you provided, here is the most useful text organized by how you might need to use it.

: Indicates the source of the dump was a digital purchase rather than a physical cartridge (which would typically use the .XCI format). Batman Arkham Knight -NSP--eShop-.rar

Purchase it directly from the official Nintendo eShop on your console. Based on the filename you provided, here is