Bip39 Dart 1 example of manually building entropy will be flipping a coin. However, if an attacker provides a coin which is weighted somewhat in favor of heads, your Preliminary supply of entropy will likely have been corrupted. Do not share: Under no circumstances share your seed phrase with anybody. https://travialist.com/story8804950/bip32-word-list-bip39-can-be-fun-for-anyone