Valmiki Ramayana Yuddha Kanda Sarga 67 Shloka 32
Original Shlokaतंशैलमिवशैलाभाःसर्वेतुप्लवगर्षभाः । समारुह्यसमुत्पत्यददंशुश्चमहाबलाः ।।6.67.32।।
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शैलाभाः looking like mountains themselves, महाबलाः endowed with strength, सर्वे all, ते of them, प्लवगर्षभाः bulls among Vanaras, शैलमिव like mountain, तम् him, समारुह्य climbing up, समुत्पत्य jumping, ददंशुः bit him.
The bulls among Vanaras themselves looking like mountains endowed with great strength climbed up Kumbhakarna and bit him.