Through the history of a Yucatecan Mayan shaman (h-men), this article analyzes the changes and continuities in Yucatecan shamanism and, more specifically, in one of its main functions: tsak, healing. The results presented here are part of fieldwork carried out over 40 years, from 1976 to 2016. The author lives in a community in central Yucatán (Tabi, Sotuta) and has carried out a number of research studies on Yucatecan shamanism in communities in the Mexican states of Yucatán, Campeche and Quintana Roo. Juan Cob, h-men of Yaxcabá, is not only an informant but also the author's friend and neighbor, with whom he has created a number of films.