 "Zangeki no Reginleiv" was the first Nintendo-published game to be rated "D" by Japan's CERO rating body, equivalent to the North American "Mature" rating.By this point, Nintendo had several third-party developers and publishers creating mature games for the Wii, but "Zangeki no Reginleiv" was their first self-published work.In response to this growing number of mature titles, Nintendo decided to create new black-edged packaging for such titles so as to help consumers identify more mature titles in the store at a glance.