From the publisher's website: Can you survive the zombie virus in this action-packed blaster from the developer of the popular Super Stardust HD? - Pit your wits against hundreds of zombies on-screen. - Blast your way with a friend in online and offline co-operative play and rank yourself with online leaderboards. - Track your zombie kills with the daily online world map and reduce the zombie virus with other Dead Nation players in the country you're playing.