High Quality Content by WIKIPEDIA articles! DayZ is a 2012 multiplayer open world survival horror mod designed by Dean Hall for the 2009 tactical shooter video game ARMA 2 and its 2010 expansion pack, ARMA 2: Operation Arrowhead. The mod places the player in the fictional post-Soviet state of Chernarus, where an unknown virus has turned the population into undead zombies. As a survivor with limited supplies, the player must scavenge the world for supplies such as food, water, weapons and medicine, while killing or avoiding both zombies and other players - in an effort to survive the zombie apocalypse.