The difference between Outer Gang and Acupoint Opening lay in reopening the human body's Xuan Pass and unlocking the Heart Apertures. However, using True Gang to open the body's Xuan Pass was rather difficult.
Therefore, one needed to circulate True Gang through the body in three major cycles. Only after the limbs, bones, the Twelve Principal Meridians, and the Eight Extraordinary Meridians fully adapted to the True Gang's intensity could they attempt to strike the first Heart Aperture. Successfully striking through the first Heart Aperture meant stepping into the Acupoint Opening Realm. In the Acupoint Opening Realm, one needed to break through a total of five Heart Apertures. This was the so-called "five apertures for the five internal organs."
