Valmiki Ramayana Yuddha Kanda Sarga 41 Shloka 90
Original Shlokaतत्पफालपदाक्रान्तंदशग्रीवस्यपश्यतः । पुराहिमवतश्शृङ्गंवज्रिणेवविदारितम् ।।6.41.90।।
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पदाक्रान्तम् trampled by, पुरा earlier, वज्रिण Indra, विदारितम् broken, हिमवतःशृङ्गमिव Himalayan peak, दशग्रीवस्य Ravana's, पश्यतः as he was looking, तत्पफाल cleft
As Ravana was looking, Angada trampling his feet gave way to the palace just as Himalayan peak broke to hit Indra.