"What is this , is it unable?" is "이뭐병"(i-mwŏ-byŏng) in Korean.
It stands for '이건 뭐 병신 도 아니고' (E gun mo byeongsindo Anigo). The abbreviation of "What is this, is it unable?" when the opponent took the unknown behavior meaning, in the words It means cursed opponent, is a slang used in between the teens.