The art of Koppojutsu teaches its students how to attack directly to the core of a threat. On the simplest, and purely physical level, this means attacking an enemy's skeletal system (the core frame of his body). As the student progresses, he will begin to understand and implement this philosophy to overcome an enemy mentally and eventually spiritually. The techniques of Koppojutsu are direct and extremely efficient. They typically have few movements and end quickly, with each attack maximizing the pain, physical damage, and mental stress dealt, while preserving the student's energy, balance, and power.
When Koppojutsu attacks are performed properly in a real life-and-death scenario, the attacker loses the ability to use his body properly because of the damage to it's core structure. He loses the ability to breathe and think properly due to the high degree of pain caused by each attack. But most importantly, he has lost completely the will to fight, and has been conquered on the fields of body, mind, and spirit. Due to the nature of Koppojutsu's techniques, they are reserved for advanced students who have proven their discipline and spiritual refinement.
The traditional schools of Koppojutsu offered are Koto Ryu Tanemura-Ha and Gikkan Ryu. After black belt the student will be eligible to test for rank within these traditional schools. Koppojutsu developed alongside Kosshijutsu, although its linear, forward motion is very different from Kosshijutsu's circular, fluid style. Together they comprise most of the core techniques of Ninjutsu, and could be thought of as it's "In" and "Yo" (Japanese Yin & Yang). When a student has developed proficiency in both Koppojutsu and Koshijutsu they are a true force to be reckoned with. Historically, Iga Ninja would master the techniques of Koto Ryu Koppojutsu and Gyokko Ryu Kosshijutsu before moving on to the advanced techniques of the infamous Togakure Ryu.