A very powerful Solo Numbering Skill. Rank 1
The strongest skill known to humanity. It is a skill which Kim Kangtae, the strongest human, uses. Kangtae trusted this skill to constantly heal him and fought like a mad warrior in the frontlines for as long as he didn't die.
This skill is famous on its own but was made to be considered the Number 1 skill known to humanity due to Kim Kangtae's exploits. This skill, which has the highest efficiency out of the discovered skills, wouldn't lose out even when compared to the Zero Numberings.
Immortal Soul's mastery increases only when one's body is shredded apart and one's soul felt in danger of destruction. This requires battles full of tension and danger. Immortal Soul grows faster when it receives many different types of external stimuli. Upon mastery, one becomes a Transcendent. The regeneration ability evolves to match the recovery rate of an immortal. This is the 3rd skill Hansoo develops to Transcendent-level.
Immortal Soul turns the user's body close to an immortal's. It allows one to fight like a "Mad Immortal" in the battlefield with no worry about injuries or stamina due to the extreme regeneration granted by the skill. It can regenerate new tissues and life force, mend broken pieces of one's body, and even regenerate lost limbs.
Immortal Soul raises one's soul and body to the extreme. Its main power is survival and it utilizes every skill and everything one has to survive. It can heal the soul with mana and can create a foundation for the Skills of Annihilation (Zero Numbering) to grow.