Valmiki Ramayana Yuddha Kanda Sarga 55 Shloka 16
Original Shlokaसर्वेह्यतिबलाःशूराःसर्वेपर्वतसन्निभाः ।।6.55.16।। हरयोराक्षसाश्चैवपरस्परजिघांसवः ।
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परस्परजिघासवः intending to kill one another, सर्वे all, हरयः Vanaras, राक्षसाश्चैव even Rakshasas, अतिबलाः of extraordinary might, शूराः warriors, सर्वे all, पर्वतसन्निभाः resembled hills.
Intending to kill one another both Vanaras and Rakshasas who resembled hills, also of extraordinary might and heroic fighting.