Valmiki Ramayana Yuddha Kanda Sarga 52 Shloka 23
Original Shlokaतत्सुभीमंमहायुद्धंहरिराक्षससङ्कुलम् । प्रबभौशब्दबहुलंशिलापादपसङ्कुलम् ।।6.52.23।।
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सुभीमम् very frightful, हरिराक्षससङ्कुलम् monkeys and Rakshasa groups, शिलापादमसङ्कुलम् with rocks and trees, शब्दबहुलम् loud noise, महत् great, तत् युद्धम् that battle, प्रबभौ abounded.
The monkeys and Rakshasa groups took part in a fierce fight with rocks and trees abounding loud noise.