Codex Enigmatum is a real, physical book. Several puzzles require physical manipulation, writing and/or drawing on the pages, so the e-book format does not lend itself well to this type of book. An e-book version is therefore not currently foreseen, though an adapted edition may eventually be produced.
The book is designed to allow solving the vast majority of puzzles offline. In the appendix supporting material is provided to assist with deciphering certain clues. There are only a select few puzzles which may require you to lookup a concept online.
The book offers hints for each puzzle (though consulting the hints should be a last resort). The solutions can also be found in the appendix. We also plan to setup a website with a forum where players can discuss the puzzles and exchange hints.
Yes, to a certain extent. The solution of each puzzle contributes to unlocking future puzzles. You can work on multiple puzzles in parallel, but eventually - in order to tackle puzzles later in the book - you will need to have resolved the earlier ones they depend on. The final puzzle can only be resolved once all other solutions have been unveiled.
This will vary greatly from puzzle to puzzle and from person to person, as well as depend on how sparingly you consult the hints. You may complete some puzzles in under a minute, whereas others may take you over half an hour. On average we expect the book to offer at least 8 to 10 hours of puzzling fun.
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