In the Purāṇas (see Purāṇas) of Vedism (see Vedic entries), two essential creation myths are developed from the myths of the sacred revealed, or Śruti (see Śruti) tradition. In the first creation the primal man, or Purusa (see Purusa), is also designated as ātman (see ātman) or Brahman (see Brahman) or Mahāyogin (Great Yogi). But unlike the original Puruṣa, who as sacrificial victim becomes the universe, this creator uses yoga (see Yoga) to complete the process by which Existence comes about through the release of the active female aspect of Nature or Prakṛti (see Prakṛti). In the other myth the Purusa Nārāyaṇa (see Nārāyaṇa), a form of Viṣṇu (see Viṣṇu), who has been asleep on the primeval waters, awakens during the period between two kalpas (ages) and becomes the creator Brahmā (see Brahmā) then Vāyu (the Wind) then the Cosmic Boar (see Boar, Avatars of Viṣṇu), who serves as the sacrificial diver who brings up earth from the depths (see Earth-Diver Creation). The Puranic cosmogony also contains stories of the dissolution of existence in the cosmic fire that emerges from the breath of Rudra (see Rudra), or Śiva (see Śiva). Wind and floods complete the work (see Vedic Cosmogony, Upaniṣd Cosmogony).