Baat Pate Ki: Why is `INS Mormugao` being called the deadliest warship built in India?

INS Mormugao has been inducted by the Indian Navy in its fleet. Union Defense Minister Rajnath Singh enumerated many powers by addressing Mormugao after dedication to the Navy. Why is 'INS Mormugao' being called the deadliest warship built in India?