The Celestial Dan Pool is an exceedingly rare natural formation that contains an extremely pure Yin Energy and Yang Energy. If one is able to absorb the energy within, not only would one be able to swiftly congeal a Yuan Dan, but the Yuan Dan formed will also be at least 6 stars. It appears as a tiny crystal-clear pool slightly over three meters long. One half of it continuously boiled and bubbled, while a bone-chilling mist hovered above the other half. These two parts were obviously of contrasting elements yet they were able to coexist inside this tiny pool. Only sufficient for four people.