Valmiki Ramayana Yuddha Kanda Sarga 54 Shloka 6
Original Shlokaवानराश्चापिरक्षस्सुगिरवृक्षान्महाशिलाः । प्रवीराःपातयामासुर्मत्तमातङ्गसन्निभाः ।।6.54.6।।
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प्रवीराः heroic, मत्तमातङ्गसन्निभाः who resembled elephants in rut, वानराश्चैव Vanaras also, रक्षःसु at Rakshasas, गिरिवृक्षान् mountains and trees, महाशिलाः huge rocks, पातयामासुः showered.
Heroic Vanaras who resembled elephants in rut showered mountains and trees and huge rocks at Rakshasas.