The original Aragami released in October 2016 but since then developer Lince Works has added more content in the form of Aragami Nightfall which comes as a DLC extra for those who already own the base game. For anyone else who doesn’t own either game can now purchase the Aragami:

More stealth action in this newly announced Aragami Shadow Edition from Lince Works which includes the base game, all of the content and the upcoming Nightfall DLC in one package. The game is coming to PS4, Xbox One and PC (Windows, Linux and Mac).