“Fire: the heat in your blood in the midst of a fight, the kinetic energy that makes your heart beat faster.” Jiang tapped his chest. “Water: the flowing of force from your muscles to your target, from the earth up through your waist, into your arms. Air: the breath you draw that keeps you alive. Earth: how you stay rooted to the ground, how you derive energy from the way you position yourself against the floor. And metal, for the weapons you wield. A good martial artist will possess all five of these in balance. If you can control each of these with equal skill, you will be unstoppable.”