Operation: Brimstone II was a joint internal, multi-agency war game held by the Union of Everett. Operation Brimstone II began on April 16, 2015 and ended on April 20, 2015, taking place in locations across the country. The war game included a vast variety of cooperating government agencies on the municipal, county, state and federal levels, the armed forces, the Homeland Defense System, civilian militias and native tribal militias.