Matsya Purana — Origin of Soma
लक्ष्मीर्नारायणं त्यक्त्वा सिनीवाली च कर्दमम् द्युतिर्विभावसुं तद्वत् तुष्टिर्धातारमव्ययम् //
lakṣmīrnārāyaṇaṃ tyaktvā sinīvālī ca kardamam dyutirvibhāvasuṃ tadvat tuṣṭirdhātāramavyayam //
Lakṣmī, leaving Nārāyaṇa, went to Kardama; and Sinīvālī likewise went to Kardama. Dyuti went to Vibhāvasu; similarly, Tuṣṭi went to Dhātṛ, the imperishable deity.
It does not describe Pralaya directly; it catalogs divine associations used in Purāṇic cosmology to map how powers (fortune, radiance, contentment) relate to progenitors and deities who sustain creation.
Indirectly, it supports the Purāṇic worldview that social and ritual order rests on cosmic order; kings and householders uphold dharma by honoring these deities and lineages through prescribed worship, gifts, and rites.
No Vāstu rule is stated, but the named deities (especially Lakṣmī and Agni/Vibhāvasu) are key in ritual sequences—Lakṣmī for prosperity rites and Agni for consecration/fire rituals that accompany temple and household ceremonies.