A yantra is an Indian mystical diagram representing a deity or cosmic power, often inscribed with mantras. The diagrams are symmetrical patterns, often involving triangles, emanating from a central point, which have a “entraining” or hypnotic effect on the mind. They are similar to mandalas, but simpler and more geometric. They are used as temple decoration, on walls or floors, as well as objects of contemplation to induce concentration. The use of yantras goes back thousands of years, and are thus coterminous with the soma cult and were probably used in combination with soma to induce altered states of consciousness.