Used alone, the ayahuasca liana appears to be of not producing any kind of vision; it must always be mixed with another plant derivative. The most common feature of Shipibo-Conibo is to add the leaves of chacruna (Psychotria viridis), but other "master plants" is not unlikely to be added. The preparation of ayahuasca is obtained by boiling in a large pot full of water for a period of six to 12 hours, pieces of the ayahuasca's liana together with the leaves of the chacruna. I remember that drug preparation does not follow fixed rules, by noting certain differences between both shaman and other, or between shaman and other shaman shamans.