The connection between fingernails and the soul dated back a long time. Like hair, they were believed to be the rings of a person's life, recording everything about their past.
Of course, this belief came from witchcraft, and it was a mystical legend found across the globe.
From China to Africa, from South America to Scandinavia, fingernails were regarded as important spellcasting materials in the occult legends of many regions.
However, in American comics, these traditional practices had a different name on the Mystic Side, distinct from magic. They were called Voodoo or Witchcraft/Gu.
Interestingly, thousands of years ago, when humanity on Earth had neither communication nor efficient transportation, the uses of fingernails around the world were surprisingly similar.
They were regarded as a part of the soul.
In China, one traditional method of cursing someone involved gathering an enemy's fingernails, then having a professional such as a witch doctor or shaman perform a ritual. It was said this could make the enemy's entire body rot away and leave them without descendants.
When Su Ming was young in his previous life, he had also heard similar stories from the old security guard at the orphanage. The old man told him to keep his clipped nails safe, preferably wrapping them in paper and burning them. Otherwise, if a mouse ate them, it would turn into another Su Ming, kill the real one, and take his place.
Whether it was true or not, he did not know, but it had certainly sounded frightening at the time.
In Scandinavia, the use of fingernails had become part of mythology. It was said that Hela possessed a ship made from the nails of the dead, which would carry souls to the Underworld Heim during Ragnarök. Only such a soul ship could carry the dead across