Valmiki Ramayana 6.59.49

गच्छ यत्नपरश्चापि भव लक्ष्मण संयुगे ।रावणो हि महावीर्यो रणे ऽद्भुतपराक्रमः ।त्रैलोक्येनापि सङ्क्रुद्धो दुष्प्रसह्यो न संशयः॥

gaccha yatnaparaścāpi bhava lakṣmaṇa saṃyuge |rāvaṇo hi mahāvīryo raṇe 'dbhutaparākramaḥ |trailokyenāpi saṅkruddho duṣprasahyo na saṃśayaḥ ||

Our plain-language meaning of this verse is waiting for scholar review.