"Viper 's Creed ," the story of the background in the 21st century , due to various human activities lead to environmental pollution and deterioration , famine, the spread of pathogens and meteorological anomalies , international economic and therefore serious problems , and finally lead to the outbreak of World War Falling apart after the end of the war , the loss of past communications and means of transportation in the world , with important geographical location is this called " FortDiversity , areas . National enterprises and companies are concentrated in this region , the friction with local residents is inevitable , in addition there are many people in rebellion . At a time when working in the private military organization to maintain order " Alcan (tentative nameアchildrenコnn ) " Clara " (tentative translation ,サku raコ) was transferred to the top unit UNIT ・ VIPER ", and Saich ( provisional translation ,サイキ) became partner to solve the various conflicts .