Valmiki Ramayana Yuddha Kanda Sarga 71 Shloka 27
Original Shlokaदशग्रीवोमहातेजाराजावैश्रवणानुजः । भीमकर्मामहोत्साहोरावणोराक्षसाधिपः ।।6.71.27।।
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दशग्रीवः tenheaded, महातेजाः highly brilliant, राजा king, वैश्रवणानुजः brother of Vysravana, भीमकर्मा of terrible deeds, महोत्साहः highly exploitative, रावणः Ravana, राक्षसाधिपः king of Rakshasas.
"The tenheaded and highly brilliant king Ravana, who is the brother of Vysravana, is of terrible deeds and highly exploitative."