Killer.io is an IO game in which you have to transform into a killer. You will have to work with other killers to turn the peaceful and crowded city into a deadly city. Your mission is to kill people and make sure the police can't arrest you. Do not perform duties in crowded places or stand next to a murderer who has been seen by the police. The game is just one of the simple IO games. With this crazy friend drama, can you become the winner?