In the future, there was a disease about 50 years ago. Scientists created a vaccine to help people, and there was peace for a while, until people started getting strange powers. Now, there are no powers are allowed. Some people have powers or smuggle Serum X to people who want powers for money. Bounty hunters try to catch mutants and smugglers. If caught, the mutants/smugglers are shipped to a concentration camp where they have to fight for their lives in a virtual reality arena for the entertainment of the rich. If you die in the arena, you get injured in real life, and the wardens give out medicine, food supplies, and other stuff, like mods, depending on what score you get per day. If you get lower places every time you play, you slowly starve or die from your many wounds.
Powers are caused if you have Serum X in your veins and if you had a traumatizing experience that awakened your fight-or-flight sense. Then you got powers that are either related to the accident, related to your passion, related to your personality.