Found in Night - Ben Alderson

Life has not been the same since the attack on the ship. Affected by the Druid's power, something dark lurks within Hadrian Vulmar, threatening the existence of those around him. Following a lead, Zacriah and Nyah head into the forest on an expedition to cure him. When they are ambushed by the living dead—bodies controlled by shadow—covered in the Druid marks, they know the Druid did not perish in the sea as they first thought. The Druid is back, and with his return comes the threat of attack. The three known Dragori are sent on a dangerous quest to stop this dark magick before Hadrian gives into his new power, and the shadowbeings end more innocent lives.