Knockout

Knockout, also known as the knockout game and knockout king, is a violent activity played by teenagers. The object of the game is to render unconscious (knockout) an innocent pedestrian with one punch. The game can result in serious injuries or death for its victims. Players face criminal charges.
In 1992, a teen stabbed an MIT student through the heart, killing him. In another case, a St. Louis, Missouri teenager allegedly attacked a pedestrian who hit his head on the ground and died in hospital. In May 2013, a 51 year-old man died from his injuries after he was attacked in Syracuse, New York, by two teenagers.