This mechanic has players playing according to a set of rules and circumstances surrounding a story element, usually one in a series of events players can choose from. Along with the instructions, Memoir '44 comes with a scenario guide. This guide contains rules and a map to adjust how the board is laid out according to which real life World War II battle it was designed after. This allows players to play each game according to a set of rules that reflect the real world campaign surrounding D-Day.