5 books in series

The Heroes of Olympus

The Heroes of Olympus is a 7-book series with 5 released primary works first released in 2010 with contributions by Rick Riordan and Nick Chamian.

The Lost Hero
The Son of Neptune
Percy Jackson y la vara de Hermes
The Mark of Athena
The House of Hades
Percy Jackson and the Greek Gods
The Blood Of Olympus