The Cakrasaṃvaratantra, the oldest tantra of the Saṃvara scriptural cycle, is the first to teach the yoga of the donkey-shaped [deities] （gardabhākārayoga）, which is also called the donkey yoga （gardabhayoga）. A practitioner devotes himself to the yoga of the ḍākinīs （particularly Lāmā, Rūpiṇī, Ḍākinī, and Khaṇḍarohā）, who each have the face of a donkey in order to stop a rush of thought that occurs in himself. By this yoga, he can know whether his target dies soon; what the target’s previous lives are; and whether the target is a seven-birther （saptajanman）, i.e., a man reborn as a human seven times in a row. Some texts composed after the Cakrasaṃvara present developed forms of this practice as follows: （1） effects of this practice are diversified; （2） the number of deities is increased （from ḍākinīs to the fivefold maṇḍala of Heruka that includes those ḍākinīs） and not only faces of donkeys but faces of other animals are visualized; and （3） this practice is internalized in the form of the psychosomatic yoga centered on the cakra and the channels （nāḍī） in the body.
