So this idea has been floating around in my head for awhile and I decided to introduce this idea for a campaign/ world setting. Devastation takes place in a world where both the heroes and villains of the marvel and dc universes existed but unlike being a hero fighting alongside these well-known heroes this setting takes place 15 years after a world-spanning war between the heroes and villains occurred. This war will be known as the power war and it causes major destruction around the globe and the majority of both sides die in this war and the destruction caused results in the world to basically be like the world of old man logan but on a global scale. Some of the heroes and villains from that time who survived the war are either retired in the heroes case or given a wide birth out of fear in the villains case. The PC's will adventure throughout this world doing what they can and possibly help a new age of heroes be born or drag the world further into villainy.

That's what I have so far and I need ideas to build this world.