This book is a collection of short stories by many different authors that have been compiled by Rick Riordan. You must read the original books to understand the stories. I could only understand two stories because they were written as sequels to books I had read. One was written by Roshani Chokshi on Indian mythology and the one by Rick Riordan on Celtic mythology. I would not recommend this book. It is pretty much impossible to follow the stories, and it is a frustrating experience trying to read them.