Amiibo Key Files -

When Nintendo releases a new line (e.g., Splatoon 3 amiibo), the keys usually work because the encryption scheme is backwards compatible. However, if Nintendo issues a console firmware update that changes the handshake, homebrew devs must extract new keys. This happened in 2021 with the "Amiibo Gen 2" update, rendering older key files useless until new ones were bruteforced.

Amiibo figures use technology, specifically NTAG215 chips. These chips are encrypted by Nintendo to prevent unauthorized duplication. amiibo key files