Valmiki Ramayana Yuddha Kanda Sarga 67 Shloka 16
Original Shlokaतानिपर्वतशृङ्गाणिशूलेन स बिभेद ह ।।6.67.16।। बभञ्जवृक्षवर्षं च कुम्भकर्णोमहाबलः ।
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महाबलः mighty, कुम्भकर्णः Kumbhakarna, शूलेन those rocks, तानि them, पर्वतशृङ्गाणि mountain peaks, बिभेद ह breaking, वृक्षवर्षं च rain of trees, बभञ्ज split off.
Mighty Kumbhakarna split off the rocks, mountain peaks and the trees breaking them.