Towervale — Patrick Carman

TOWERVALE is a book and a video game at the same time, and a sprawling fantasy series for ages 9-12. Towervale is organized in seven sections that are not in order. Each section ends with a password you must enter in the Towervale game, unlocking a level. When the level is cleared, the next page to turn to in the book is revealed. But there's a catch: if you didn't read the previous section of the book, you'll have no idea how to clear the level in the game (free game access included with each book - web, app). Your adventure begins in the Caves of Iron and takes you through three realms where you'll encounter a world beyond your imagination and a villain of unparalleled danger.