Since the Yin body was a body-nourishing method specific for the darkness element, it was obvious that the absorbed "Breath" would be of that same element.
The Seven Hells method didn't distinguish between them and had freely stored "Breath" of various types but, with the new method, that "Breath" had become a hindrance for the advancement of the body.
The dark gas slowly filled his body, lowering its temperature.
Noah endured the coldness and pushed the new "Breath" toward the dantian.
The dantian then refined the gas and dispersed it through his skeletal system.
His bones began to emit a soft aura that slowly nourished the other parts of his body.
'So that's how it feels like to use a method that requires the dantian.'
The refinement of the dantian was necessary for the process to render the cold "Breath" absorbed by his acupoint harmless.
If his body tried to directly assimilate it, it would create a great deal of damage.