Matsya Purana — The Syamantaka Jewel Episode and the Vrishni–Sainya Genealogies
कदाचिन्मृगयां यातः प्रसेनस्तेन भूषितः यथाशब्दं स शुश्राव बिले सत्त्वेन पूरिते //
kadācinmṛgayāṃ yātaḥ prasenastena bhūṣitaḥ yathāśabdaṃ sa śuśrāva bile sattvena pūrite //
Once, Prasena went out on a hunt, adorned with that splendid gear. Just as the sound arose, he heard it within a cave that was filled with a living creature.
This verse is not about Pralaya; it is a dynastic narrative detail describing a hunting expedition and an ominous cave scene, setting up later events rather than cosmology.
It reflects the royal practice of mṛgayā (hunting), often portrayed in Purāṇic stories as a context where vigilance, restraint, and responsibility are tested—since a king’s actions in the forest can trigger wider consequences.
No Vāstu or ritual procedure is stated directly; the only spatial element is a “bila” (cave/hole), used as a narrative setting rather than an architectural prescription.