After the Flash: Overcast is a prequel to Mirage, set at least a couple of decades before Mirage and is set in Oregon. It's the same map layout but it now has trees and forests. As well as some new outposts. It's 2041 and the nuclear war is still raging on.
The USA's global influence is what led to a new disease, new factions and bigger issues for the governments around the war that struggled to maintain certain things. For decades they went through many, many political arguments, and economic crises. They tried to maintain foreign relations but that failed and caused the fall of America. In mid 2020 they realized they couldn't manipulate and lie about world politics like they used to which put the government in a heavy state. At the time the ACMF was trying to achieve certain goals in Asia, which led to the invasion of China's Taiwan in 2028. The United States was now desperate which caused them to intervene. Once the ACMF found out about this they set a conflict between themselves and the USA. NATO intervened and helped ACMF, but with only a small number of troops. These chains led up to the invasion of the west coast in the United States in 2032. After this, the famous name appeared, "The Flash" After this, the country went silent. The nuclear war happened, causing the conflict between the USA and ACMF to break. The government collapsed as the nuclear war settled in for a decade at least. The land was ruined even more and some tried to piece the puzzle back together but had very little hope, giving up very shortly.
The year is now 2041, the nuclear war is still going on and has sent hundreds of people back to a country called Oregon in a small region that hasn't been touched and burned into ashes like many other places. Though, it's just another apocalyptic place, but this time it has a new disease, a new virus.