The street name is "knockout."
The game begins when a group of teens randomly pick out an unsuspecting bystander, then as the group and target pass on an urban street, bam: swift fist to the jaw.
Most of the time, the bystander is unconscious before they hit the ground and never know what hit them.
The game, mostly played in New York and New Jersey, has sparked national outrage for its cold-hearted brutality and complete disregard for human decency.
In the video above, a group of New York teens pass by a Jewish man on a Crown Heights street corner.
The man, seen in a white hoodie, is punched right before he turns the corner, but doesn't get knocked out.
He's considered "lucky."
Follow Tommy Rowan on Twitter: @tommyrowan
Follow Metro Philadelphia on Twitter: @metrophilly
Follow Metro Philadelphia on Facebook: Metro Philadelphia