Akatsuki EN-Eins (アカツキ/エンアイン, Akatsuki EN-Ain) is a series of Japanese dōjin 2D fighting games, developed by the dōjin circle SUBTLE STYLE for Microsoft Windows and arcades. It takes place in an alternate 21 century in the year 200X - 20XX, where most of its characters wears outfits from World War II era.