Valmiki Ramayana Yuddha Kanda Sarga 69 Shloka 12
Original Shlokaसर्वेसुबलसम्पन्नास्सर्वेविस्तीर्णकीर्तयः । सर्वेसमरमासाद्य न श्रूयन्तेस्मपराजिताः ।।6.69.12।। देवैरपिसगन्धर्वैस्सकिन्नरमहोरगैः ।
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सर्वे all, सुबलसम्पन्नाः possessed stupendous strength, सर्वे all, विस्तीर्णकीर्तयः very well known for their fame, सर्वे all, समरम् in war, आसाद्य accompanied by, सगन्धर्वैः Gandharvas, संकिन्नरमहोरगैः even if they are Kinnaras, देवैरपि gods also, निर्जिताः will be vanquished, न श्रूयन्ते स्म never get defeated.
All sons of Ravana possessed stupendous strength, all were very famous, and never got defeated in war be it Gandharvas, Kinnaras or even gods will get vanquished by them.