Colin Moriarty writes: One of my favorite games on PlayStation Network is the exclusive Dead Nation. From developer Housemarque, best known for another PSN exclusive known as Super Stardust HD, Dead Nation is a violent, dark, zombie-infested twin-stick shooter that will test your very mettle as a gamer. The thing is, Dead Nation is more than just one hell of a game. Housemarque's attention to keeping gamers involved with complex and engaging leaderboards, multiple difficulty levels and a full roster of Trophies (including a Platinum -- a true rarity on PSN) is a testament to Dead Nation's long-burning potential. And now, it has DLC.