If you have lost a physical amiibo but previously backed it up, you're fine. If you're looking for "every amiibo ever made" in one zip file, those do exist on certain forums and the Internet Archive, but they are taken down frequently.
If you don't want to buy physical tags, you can "install" the .bin files into emulators on a PC or modded console. amiibo backup bin files install
But Jack didn't stop there. He wanted to learn more about how the backup process worked and how he could use the bin files to restore his amiibo data if needed. He spent the afternoon reading through the forum posts and developer notes, learning about the intricacies of amiibo data and the clever techniques used to extract and store it. If you have lost a physical amiibo but