That’s why I tend to lean towards either Mr. Gold or Baelfire writing the book.
What if Rumple used magic to create the book? Maybe a spell was able to write down all of the charcters memories into it. This would explain how he got everyones personal details. Plus, *insane theory alert* maybe the reason Regina did not simply destory the book (which would prevent Henry from knowing about FTL) is because it would have badly affected everyone in SB.
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