You are likely looking for key_retail.bin (which consists of locked-secret.bin and unfixed-info.bin ) to unlock the encryption on Amiibo dump files.
modding and getting the error "This folder doesn't contain the 'encryption_key.bin' file" : Encryption-key.bin File Download
An encryption-key.bin file is a binary file that contains a cryptographic key used for encrypting and decrypting data. These files are often used in various applications, including secure communication protocols, data storage solutions, and software licensing systems. The contents of an encryption-key.bin file are typically encrypted and require a specific password or passphrase to access. You are likely looking for key_retail
If you need an encryption key for a development project (like Python or OpenSSL), you should rather than downloading one. The contents of an encryption-key
Searching for "encryption-key.bin file download" often leads to untrusted websites, forum threads, or YouTube descriptions. There are two major risks: