Teens are playing a very deadly game called "knockout." Teens are randomly gong up to people to try to knock them out. I think this really stresses the need for us to be alert and very aware of our surroundings. The victims dont have opportunity to react, block/counter seems useless; awareness and avoidance, as always, is the best answer. BTW- Im not condemning or putting any of the victims at fault, so as much as just illustrating how important it is for us to be on the alert.