Valmiki Ramayana Yuddha Kanda Sarga 29 Shloka 26
Original Shlokaप्रेक्षमाणाश्चमूंतांतुबभूवुर्भयविक्लबाः । तेतुधर्मात्मनादृष्टाराक्षसेन्द्रेणराक्षसा ।।6.29.26।।
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तेराक्षसा those Rakshasas, तांचमूम् that army, प्रेक्षमाणा started looking, भयविक्लबा bewildered with fear, बभूवु remained, धर्मात्मना righteous one, राक्षसेन्द्रेण Rakshasa king (Vibheeshana), दृष्टा on seeing.
Those Rakshasas were bewildered with fear on looking at the army. Righteous Vibheeshana recognized them on seeing them.