Eternal Sacred King - Chapter 86: Power of Blood

... izations came through to him like seeds germinating.

This was the reason why The Mystic Classic of the Twelve Demon Kings of the Great Wilderness was getting more difficult to cultivate – it was a process of internalizing external qualities.

The skin was the first to be tempered, followed by the flesh, tendons, bones. After that sequence, the marrow would be refined – that was the Marrow Cleansing section.

External cultivation techniques were relatively easier to master.

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