The author gives fair warning at the start: This book swims in RPG-character-development computations. If that's not your cup of tea, you're not going to enjoy the book, regardless of its other merits. So this review (and the accompanying rating) assume that the reader can enjoy a swim in power-gaming number crunching.
"The Power of Ten" is a gaming system that starts at D&D (3e, mostly) and pulls in elements from whatever other system suits the author. To an extent, the book is a love letter to RPG exploits. The game mechanics of D&D and similar games are tuned for moderate character levels. At high enough levels, game balance goes out the window. In this book, the author takes that 'problem' and runs with it: Sama Rantha is what happens if a character is allowed/encouraged to seek out every exploit and run with it.
The core story is not strong. The book's focus requires hundreds and hundreds of pages of fight scenes, alternating with "this skill, coupled with this amulet, lets you deal triple damage to monsters with toe nails" and its numerous cousins.