Valmiki Ramayana 4.39.21

महा अचल निभैः घोरैः पनसो नाम यूथपः ।आजगाम महावीर्यः तिसृभिः कोटिभिः वृतः॥

mahā acala nibhaiḥ ghoraiḥ panaso nāma yūthapaḥ |ājagāma mahāvīryaḥ tisṛbhiḥ koṭibhiḥ vṛtaḥ ||

Our plain-language meaning of this verse is waiting for scholar review.