I thought this book was amazing! I loved every bit of it -- the idea behind the book, the characters, and everything else. The characters were very well developed; I felt as if they could be real people that I might meet in my everyday life. The conversations were very natural. Also, I loved the idea of the spheres; the idea of colored orbs that could physically improve you in some way or another was very fascinating. I know with some books when you read the summary, and then read the book, it lets you down. But this was definitely not the case with this one. It did take a bit of a strange turn at the end, but I felt like it somewhat worked together with the story. This book kept my attention from the first page to the last with mass amounts of action. I would recommend this book to ages 12 and up, as there is some mature wording and themes.