The only legal and reliable way to obtain them is by dumping them directly from your own, legally owned 3DS console using custom tools. The Recommended Method: Using GodMode9 Ensure your 3DS has Luma3DS installed.
You can create this file by using a text editor to paste specific key values. A typical, functional section of the file appears as follows, though the actual keys are 32-digit hexadecimal strings: 3ds aes-keys.txt
If you prefer not to manage an aes-keys.txt file on your computer, you can use GodMode9 on your 3DS to completely decrypt your game dumps ( .3DS or .CIA files) before moving them to your PC. A fully decrypted game file bypasses the need for an emulator-side key file entirely, streamlining your workflow. To help tailor this guide further, let me know: The only legal and reliable way to obtain
The file must be explicitly named (ensure your operating system hasn't accidentally named it aes-keys.txt.txt by hiding file extensions). A typical, functional section of the file appears