Players like having characters that possess great power. However, the greater power one has means that they need more powerful opponents. It quickly gets to the point where normal people are unable to properly deal with those characters. What happens when criminals gain abilities, technology, or something else that is more than normal law enforcement can deal with? Most established groups like Avengers, JLA, etc deal mostly with more powerful threats and government agencies are ment to deal with characters at that level. This leaves the street level characters with little to no backup that is properly qualified. How is this addressed in your campaign, if at all?