兩虎相爭,必有一傷 [ㄌㄧㄤˇ ㄏㄨˇ ㄒㄧㄤ ㄓㄥ , ㄅㄧˋ ㄧㄡˇ ㄧ ㄕㄤ; liang3 hu3 xiang1 zheng1 , bi4 you3 yi1 shang1] if two tigers fight, one must get injured (idiom); if you start a war, someone is bound to get hurt ◄ ►