The PC version of Ys IX: Monstrum Nox now supports cooperative multiplayer, a tidy little post-launch bonus for Nihon Falcom's action-RPG. Nadia Oxford told us last year that for fans of the genre, "the Ys series is a must-play, and Ys IX is as good a place to start as any." Co-op makes it an even nicer place to start because friends are nice, aren't they?