Valmiki Ramayana Yuddha Kanda Sarga 108 Shloka 29
Original Shlokaनिपेतुरिन्द्राशनयस्सैन्येचाप्यसमन्ततः ।।6.108.29।। दुर्विषह्यस्वनाघोरंविनाजलधरोदयम् ।
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जलधरोदयंविना without clouds, घोरम् terrific, दुर्विषह्यस्वनाः unbearable sound, इन्द्राशनयः thunderbolts of Indra, अस्य on his, सैन्ये army, समन्ततःall over, निपेतुःdropped
Without clouds, terrific thunderbolts of Indra (rain) dropped on his (Ravana's) army all over causing unbearable sound.