Electromagnetic Pulse. death. the burned walking the streets. hell on earth. you will walk an see the dead, burned. the people trying to survive. the government trying to keep control. gangs going mad. tribes forming. but mostly death. Chemical Radiation. Third-degree burns extend throughout the layers of skin and are often painless because they destroy the pain nerves. They can cause severe scarring or disablement and can require amputation.
Initial blast and radiation.  GOOD LUCK MATE!!!!!!!!!