Translations of the native notion of shamanic agency of the Siona Indians of Colombia is explored throughout different historical and social contexts. The polysemic concept rau is central to the shaman’s capacity for establishing relations of exchange and negotiation with humans and non-humans. As the embodiment of his power, it fits within a semantic field that conveys the waxing and waning of life cycles. Sharing a series of qualities with the Melanesian concept of mana, rau should be understood as a social phenomenon whose use and meaning has transfigured through time and space. However, unlike the globalization of new mana, the important notion of Siona shamanic agency has been substituted by representations of the ritual substance of yajé as key symbol for power and knowledge as Siona rituals have been revitalized in their dialogue with the ethnic identity movement and the neo-shamanic network that associates sacred plants with primordial knowledge and agency.