Valmiki Ramayana Yuddha Kanda Sarga 88 Shloka 6
Original Shlokaअद्यमत्कार्मुकोत्सृष्टंशरवर्षंदुरासदम् ।।6.88.6।। मुक्तंवर्षमिवाकाशेवारयिष्यथसंयुगे ।
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अद्य and then, संयुगे in war, मत्कार्मुकोत्सृष्टम् see my valour and prowess, दुरासदम् difficult counter, आकाशे sky, मुक्तम् released, वर्षम् इव like rain, शरवर्षम् shower of arrows, वारयिष्यथ will not able to stop.
"See my valour and prowess now. I will release shower of arrows from the sky like rain and it will be difficult for others to counter."