Through ethnographic data, the author presents the still little known bimo metaphysics and unravels the complexity of the local text-based ritual system in which the continuity of each bimo lineage relies on the transmission of manuscripts whose writing relates to lineage blood. While illuminating the usages of this shamanistic tradition that is characterized by scriptural variability between patrilineages, Aurélie Névot highlights the radical changes it is undergoing by becoming a Chinese state tradition.