The boy with the mark of light

It's the first book of the adventure of Sicarda, the young prince of the Lotus Kingdom. The once peaceful and prosperous country turned into dark era as King Lumi, prince Sicarda's father was assassinated, Sicarda was taken away by Golden warrior who was being accused as the assassinator. The successor of the crown determined to bring Golden warrior to justice, but who is the real assassinator and what exactly happened to the prince?