3 books in series

Saint Seiya The Lost Canvas Gaiden

Saint Seiya The Lost Canvas Gaiden is a 1-book series first released in 2011 with contributions by Shiori Teshirogi and Masami Kurumada.

聖闘士星矢 THE LOST CANVAS 冥王神話 外伝 1
聖闘士星矢 THE LOST CANVAS 冥王神話 外伝 2
聖闘士星矢 THE LOST CANVAS 冥王神話 外伝 3