The human body has two types of energy flowing through it. Ki and reiki, people who can control ki are fairly numerous. Many martial artists can eventually develop their control to such an extent that they can manipulate their body’s life force, or their ki, to do all sorts of special attacks. The legendary Chestnuts Roasting on an Open Fire for example puts ki into the arms to increase its punching speed, Reiki is different however. Some people, about one percent of the total human population, are born with a kind of power that separates them from the others. This power manifests differently in all of them and is as unique from person to person as fingerprints and voiceprints, but it all connects and concentrates on one thing, the soul. These rare individuals, called physics, have the ability to access the power deep within them and call it forth whenever needed, most of the time they don’t even realize it. However precognition is only one of the many abilities that physics’ posses.
Now, out of the one percent of the people in the human race that actually have any spirit strength, only one percent of those people have enough to put it to any use, and only one percent of that one percent have developed it to use efficiently. Spirit techniques differ from regular techniques because of the great amount of damage you can cause with them as well as the almost endless possibilities. Spirit fighting techniques aren’t just meant to destroy someone’s body, they can also erase that person’s soul from existence altogether, not to mention alter the molecular structure of things in ways you could never hope to do with ki.