Valmiki Ramayana 7.53.22

भारावतरणार्थं हि नरनारायणावुभौ ।उत्पत्स्येते महावीर्यौ कलौ युग उपस्थिते॥

bhārāvataraṇārthaṃ hi naranārāyaṇāvubhau |utpatsyete mahāvīryau kalau yuga upasthite ||

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