The battlefields of ancient Japan were typically overrun by fierce and dangerous men, often hidden by armor or covered with blood. Both the samurai and the ninja had to decide--in the blink of an eye--who was a friend and who was an enemy. A fleeting glance was all the time they had to make their determination. In that life-or-death instant, they knew an overzealous strike might kill an ally, while a delayed decision might cost them their life. Yet for those warriors trained in Ninso, that glance was all that was needed to accurately read the intent on a stranger's face.