The Gandharvas are a class of spirit in Indian folklore. They are male, and are sometimes said to be the 'husbands' of the Apsaras. They are sometimes described as half-man, half-bird and were renown for having great skills at music and the power to cast illusions. They are said to dwell in forest & mountain regions, and like many such beings in Indian myth, are sometimes friendly to humans, and sometimes inimicable. In some myths, the Gandharvas are said to be guardians of the heavenly Soma. A tale which first appears in the Rig Veda concerns King Pururavas who, after falling in love with a nymph, enjoys a tryst with her until the lovers are seperated by the Gandharvas. The King entreats the Gandharvas for a boon, and they tell him of a ritual by which he can become a Gandharva, and so rejoin his lost love. There are similar stories in which humans become spirits, such as the ganas.