Spent a lot of time trying to solve the final mystery, and then was given a completely different answer by the secret hidden answer key - I'm wondering if the makers made a mistake, actually. Which would be surprising given how much effort they put into the rest of the puzzles. A mixed bag of them, some were easy when I was a kid, some still stump me at 31 - genuinely deserves the warning message on the front cover. Still a favourite, as the world-building, if simple (all the countries are named after food, which I didn't get as a kid), hints at something larger than the book. A real world I'd like to explore. And all the storylines are interconnected. Something something time travel???? ( )

I received this book as a gift when I was young, and the puzzles with their complex, enigmatic back story fascinated me (my parents were probably just happy that I was keeping out of their hair!). Years later, I still look over this book and feel that same sense of wonder. And there are still facets of the central mystery I haven't yet solved -- if anybody knows the whole story of the Stone, I'd love to find out! ( )