Nsc Builder Keys.txt ((link)) -

you can merge Switch games, updates and dlcs into a single file

: Avoid merging files that already have updates/DLC integrated into a "SuperNSP" multiple times, as this can lead to corruption. Renaming errors nsc builder keys.txt

The only legal way to obtain keys.txt is to dump the keys from your own Nintendo Switch console. This requires a Switch that is vulnerable to the "fusee-gelee" exploit (or other entry points) and a PC. Tools like are standard for dumping these keys from the console's firmware. you can merge Switch games, updates and dlcs