The powerful prayer for protection, Narasimha Kavacha Stotram is described by Prahlada Maharaja in the Brahmanda Purana, which states: 

गर्जंतं गर्जयंतं निजभुजपटलं स्फोटयंतं

हरंतं दीप्यंतं तापयंतं दिवि भुवि दितिजं क्षेपयंतं रसंतं ।
 

कृंदंतं रोषयंतं दिशिदिशि सततं संभरंतं हरंतं ।
 

विक्षंतं घूर्णयंतं करनिकरशतैर्दिव्यसिंहं नमामि ॥