2014 spinoff the Percy Jackson and Kane Chronicles series
The Staff of Serapis is the sequel to The Son of Sobek and the second book in the Percy Jackson and the Olympians/The Kane Chronicles crossover series. It was released in the back of the paperback version of The Mark of Athena on April 8, 2014 and as a single e-book and single audio book on May 20, 2014. On April 5, 2016, it was released as the second of three short stories in a hardcover novel entitled Demigods and Magicians: Percy and Annabeth Meet the Kanes.[1][2]