Solo Leveling Wiki

Essence Stones are small glowing stones that are found inside the corpses of magic beasts. They are generally very valuable and serve as the primary source of income for hunters around the world.

Naturally, an essence stone's worth is determined by its rank and quality. As a result, E-Rank essence stones sell for very little cash since they are so common and low-quality, while S-Rank essence stones sell for millions due to how rare and top-quality they are. It should also be noted that the color of an essence stone depends on its rank. For example, D-Rank essence stones are white, A-Rank essence stones are red, and S-Rank essence stones are purple.

Essence stones can be used to forge equipment and weapons with special properties that hunters can use in battle. It can also be used as a long-lasting and highly efficient energy source, given that Kamish's essence stone was used to power the FBH's HQ for nearly a decade.

It is later revealed that the Rulers created essence stones and implanted them inside the magic beasts that they captured during their first war with the Monarchs to have them kill humans and in turn, saturate the human world with vast amounts of mana so that mankind wouldn't be wiped out during their eventual rematch with the Monarchs.