The humans use charyeok by creating contract between themselves and the being who bestowed them the power. Before the current system, the use of charyeok was much more powerful and primitive than the current one, with gods directly infusing their godly power into a human, though at a severe cost.
Long ago, humans, monsters, and gods lived on the ancient Earth. The monsters sought to rule over the humans, whom were far weaker than they, and had not yet developed technology on a level to hurt them (humans were living in what would be considered the Stone Age). Mankind was divided and scattered, living in isolated clans, each trying to fend for themselves. Eventually, a chieftess of a human clan named Ungnyeo appealed to the distant gods to lend them their power.
The Gods agreed after much deliberation, and gave humans their power but the drawback was, every time a human used this power, they either got older or younger. There was a "prominent clan" who the gods gave their power to who saw that the cost of using the power not worth it, and sought to create their own power, thus Martial Arts was born.
The war between monsters and humans finally ended and Ungnyeo became the lover of a god, pregnant with his child. Hwanung didn't want his unborn child to experience the burden of the current borrowing system and thus sought to destroy it. The destruction of the original system caused godly power to be distributed among the humans without restriction and cost. In the end the other gods punished him for it and placed taboo upon the humans, rendering them incapable of attacking those who gave them power.
This type power borrowing is the most powerful variant. It can be used from mundanely increasing strength to granting wishes that even gods claimed to be very difficult, such as resurrection. Two of the Bishops exhibited instantaneous regeneration and transformation.
This method of power borrowing can only be used as much as its drawback. Those who become older will inevitably reach point where they're unable to use their power as they will die. Those who become younger have to wait until they get older to be able to use their power effectively.
- Ungnyeo called this and the army of monsters to be the first experiment conducted by the gods.
- It seems that activating this type of Charyeok can break ability sealing of a key, since one of the bishop, Xiao Chen, was able to activate it while at the same time under Lee Soo-Jin's ability sealing skill. But apparently that required a lot of energy as Kim Oong-Nyuh can't break it when she's in her child form.