Long Dau (ロンダウ Rondau?) is a dead language in Tales of Xillia, having once served as the court language of Long Dau nobility. Only a select elite are allowed to learn the language, and it is Wingul's native language. Upon undergoing the transformation of his booster, he speaks it fluently. Gaius knows Long Dau from Wingul teaching it to him, and Rowen J. Ilbert acknowledges that he studied it when he was young. Other than these three, there are no other known speakers of the language.