If either key is lost, the seed phrase CANNOT be decrypted. This is the risk of self custody. Unless there are other means of retrieval, the Bitcoin is gone. Legacy does not save any data.
Yes. You can create as many key-pairs you like. They can be associated with as many different seed phrases as you like.
Download "Legacy-offline.html" from gitbub. Disconnect from wifi. Open the file in a web browser.
No. Beneficiary Key and Benefactor Key may contain all uppercase, lowercase, numbers, and special characters.
The Beneficiary needs to receive:
1. Benefactor Key
2. Encrypted Seed Phrase
3. Working copy of "Legacy-offline.html"
Visit the Protocol page for detail summary.