Rather than knee-jerk nerf them to oblivion I brought up the problem with the players in the next session. Sure while there were a few hiccups and even there superpowered characters were on the ropes a few times, I did not think that would be indicative of the rest of the game. Instead those minor quibble were the players still getting the hang of their characters (and the new system). So since I was a little stumped on how to adapt what I was thinking of to match their superpowered abilities I had them try out collective world building for the first time. For those unfamiliar this is where the campaign setting is decided by consensus rather than whatever the Judge/DM/Storyteller can hastily throw together on the spot.
Rather than start off with choice of setting we worked on a few other issues until we could all agree on a common ground. First up was the issue of how the game would progress, the players unanimously agreed that they would like to start off small and work their ways up to fame and glory. Next up we talked about what kind of enemies and villains they'd like to square off against since I felt gangsters weren't up to par. We went through a few ideas, starting with villain teams ala legion of doom or brotherhood of evil mutants, steampunk nazi zombies (Sucker Punch is a favorite in our group), and mutant hunters. Surprisingly they also related that they really wanted to have gangsters as a main antagonist as they really liked the mutant drug plot point. So from there we had to decide how we wanted these gangsters to be a culpable threat. To do that we had to talk about setting and we all agreed that a fair bit of sci-fi and cyberpunk would up the ante and make dangerous foes for their superpowered shenanigans.
While we were brainstorming I had taken down a lot of notes on what they wanted such as dystopian futuristic cities but also apocalyptic wastelands (and of course zombies) then jotted down a few ideas on how to link it there and retain the few plot points we already had. Here are my notes verbatim:
The zombie apocalypse was averted by nuking most of the living world. The fallout left behind an irradiated waste and a staggering amount of mutations. The wasteland is still incredibly radioactive but it a minor issue for those already transformed (all mutants have a slight degree of rad resistance). Though the cleansing fire reached many corners of the world there are still a few pockets of zombie and ghouls roaming the wastes so many people rarely leave shelter.
This is contrasted with city-state metropolises, bubble cities. The cities are largely unscathed due to their protective domes and remain high tech wonders. Technology has advanced far enough to allow for cybernetics, robotics and genetic manipulation to come about. Although due to fuel constraints, aerial travel between bubble cities is all but non-existent.
The mass genetic mutations has resulted in two classes of citizens. Those that are normal or the pure and those that are abnormals, mutants. The normals control the city and the science and sequester the mutants to barely sheltered slums. Mutant fights were a popular sport for a time but were outlawed after enough mutants gained enough money and fame to move out of their social stratum. They have since been replaced with robot fights. Mutants are not normally allowed to walk the high cities streets after daylight which has created a shadow running life for many a mutant. The perils of night include anti-mutant watches, robotic sentinels, and of course well equipped law enforcement that are allowed to shoot on sight. It is a harsh life but it is still better than living in the wasteland.
Since the cities are very low on space the population density is very high. No longer are there individual apartments and houses. Instead people live in communal floors with few walls in large many storied buildings with rooftop hydroponic agriculture.
Mutants in the wasteland are legends and have not been confirmed yet. Morlocks live in the sewers under the highcity scavenging the few valuable commodities and resources that are not recycled. Resistance groups exist since mutants have the ability and power to fight back against the technologically superior forces.
The bubble cities are technocracies where the scientifically inclined dictate living conditions both the banal and the eye opening, something akin to Logan's Run. Even though this scientific mecca sounds somewhat nice on paper they are still as fallible as your regular congresscritter and organized crime has it's hands in many a cookie jar. Though horrifically illegal and counter to societal views these mobsters have been experimenting with genetic manipulation to create a drug which will temporarily give the user superpowers but without the nastier side effects.
The players really enjoyed the idea of mutant apartheid but wondered why mutants were so disliked and furthermore why they didn't outnumber and overwhelm the regular folk. Here is my hastily thought explanation to keep this ramshackle setting of glue and popsickle sticks held together.
"Why are mutants so disliked?
In general abnormals are about 95% likely to be infertile thus rendering them useless for the rebuilding of the human races. Also, their wide variety of uncontrollable powers automatically makes them more than eligible for causing political unrest undermining the order that will supposedly pull these bubble societies up by their bootstraps and back into a golden era."
Overall it was a pretty good attempt trying to tie all the ideas and themes together into one coherent setting. Of course players being players, two sessions later they left the infinitely intriguing bubble cities (their most requested feature) to wander the wastes and never turned back. C'est la vie.