State of Decay [Online Game Code] Decay belongs in the pantheon of great modern zombie games alongside Valves Left 4 Dead series and Telltales Walking Dead episodes. 8.9  IGN State of Decay is one of the most cohesive, terrifying and engaging open-world games I've ever played. 8.5  Polygon Few zombie games, for all their marketing power and visual sheen, can come close to providing what State of Decay does. 8.5  Destructoid