Honestly, the author of this series writing was quite good... but the story was really boring! After half of the book, I started to discourage... I don't know - should I read book 5? 
 Thinking about rereading. Probably the book is boring due to my lack of vocabulary in English and I was very busy during that time - test all day. Now I have a little bit more free time to read books and I have improved a lot in my English - so well, yeah, let's give it another try. 
 I have regard myself highly appreciated to reread this book. 
 It was not as boring as I used to think. The series flowed smoothly, endless with battles, which kind of boring for me sometimes, and the characters seemed to have one-dimensional. I mean Palamedes, Saint-German, Gilgamesh, Machiavelli... kind of sound all the same, they do not have a distinguish personality that sometimes I confused one character with one another. Well-describe characters I like: Aoife and Josh. Even though I kind of feel unfair for Josh 'cause he always plunged himself into troubles and troubles, and being persuade by John Dee too often. The most confused part is: I don't know which side too take on sometimes, but clearly it is guide the readers toward the Flamels and Sophie. I felt John Dee and Machiavelli sounds kind of right, and Nicholas - Pernelle seemed hidden something. They are too mysterious. 
 But overall, the plot is fine. I just found it so lack of romance, instead focused too much on mythology and a bunch of folklores.