"The Wizard and the Volcano" is Deca's sixth book, written by Marc Herman, published in April, 2015. The book revolves around the wizard of Mount Merapi in Java, Indonesia, a mystic figure who refuses to obey an evacuation order for an impending volcanic eruption. As conditions in temporary evacuation camps become cramped and increasingly desperate, disaster strikes unexpectedly where only the wizard had predicted and thousands of evacuated residents begin returning to their abandoned homes and livelihoods in the danger zone of the active volcano. Through the lens of interviews with the wizard, NGO reports, local legends and firsthand reporting over the course of the eruption, the book explores the role of foreign aid, government, local authorities and history in shaping how a high-stakes crisis unfolds in a disaster-prone country. The book was published on the two-hundred-year anniversary of the largest volcanic blast in recorded history, Indonesia's deadly Tambora eruption in April 1815.