Valmiki Ramayana Yuddha Kanda Sarga 59 Shloka 79
Original Shlokaअभिवृष्टश्शरौघेणमेघेनेवमहाबलः । ह्रस्वंकृत्वाततोरूपंध्वजाग्रेनिपपातह ।।6.59.79।।
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शरौघेण hail of shafts, मेघेनेव by cloud, अभिवृष्टः when rained, महाबलः mighty strong, ततः that, रूपम् form, ह्रस्वम् small size, कृत्वा reducing, ध्वजाग्रे top of bow, निपपातह landed.
When Neela was covered by Ravana's arrows, it was just as clouds cover mountain peaks. Neela reduced his size and landed on top of Ravana's bow.