Th3Unp3rc31v3D

I'm returning back to the game, and im curious if the new assassin's outfit is only a NPC outfit, or what? I want to know where it's located and how to obtain it. GIB GIB GIB tu MEH !!! Also I'm referring to the one in the latest update "Shroud of the Assassin" , not the naruto lookin one, but the black and purple-ish shinobi looking one.