两败俱伤: cause destruction to both sides; both being defeated and wounded; both sides suffer [lose].; both sides suffered [sustained] great losses (in the fierce battles).; both sides would be lose
发生内讧: be divided against itselfdivide against itself
内讧四起: civil strife coming up one after another; torn by internal strife; internal conflicts rising from all around; rent by internal squabbling
