The aim of this article is to advance our knowledge of past shamanic practices in northwestern South America through an analysis of colonial-era criminal cases of people accused of using “superstitious” healing practices. A reading of three cases from late eighteenth-century Ecuador (the colonial Audiencia of Quito) reveals details of the techniques that these healers were using. Shamans attempted to control spirits through various means, including battles, esoteric chants, and the use of tobacco, alcohol, stones, and the fangs of predatory animals. The records indicate that on Ecuador’s coast, healers practiced a type of frontier-zone shamanism in which people of different ethnoracial and cultural backgrounds engaged in shamanic practices. The research expands existing studies of the historical exchanges of shamanic knowledge, practices, and sacred objects in colonial and modern frontier zones by contributing with a regional focus on the Pacific coast of Ecuador.