Matsya Purana — Tārakāsura’s Austerity and Boon; Mobilization for War; Bṛhaspati’s Fourfold P...
नानाप्रस्रवणोपेतं नानाविधजलाशयम् प्राप्य तत्कन्दरं दैत्यश् चचार विपुलं तपः //
nānāprasravaṇopetaṃ nānāvidhajalāśayam prāpya tatkandaraṃ daityaś cacāra vipulaṃ tapaḥ //
Reaching that cave—adorned with many springs and surrounded by reservoirs of various kinds of waters—the Daitya undertook extensive austerities (tapas) there.
This verse does not describe Pralaya directly; it highlights a Puranic motif where powerful beings seek transformative results through tapas performed in potent natural sanctuaries (springs, lakes, caves).
Indirectly, it underscores the Purāṇic ethic that disciplined practice (tapas/self-restraint) yields power and outcomes; for kings/householders this translates into regulated conduct, vows, and sustained effort rather than impulsive action.
Ritually, the setting signals a tirtha-like landscape—caves with springs and water-bodies are portrayed as spiritually charged sites suitable for vows, austerities, and observances; no explicit Vastu/temple rule is stated in this verse.