Blood Essence also known as Bloodline Power is energy derived from one's body and utilizes the nutrients, or vitality, within their bloodline as a power source. In combat, Blood Essence can serve as an alternative power source to soul power and spiritual power.
It plays a significant role in influencing a soul master's potential rank and the quality of their martial souls. As a soul master grows older, their blood essence naturally diminishes, which is why the optimal time for cultivation is typically before the age of 40
There are Methods available to purify, evolve, or mutate bloodlines, such as utilizing specific techniques or items like the Emperor Fruit or fusing with a soul spirit
Bloodline Suppression occurs when a soul master with a weaker or lower-ranked bloodline fights against one with a stronger bloodline. This can cause the soul master with the weaker bloodline to feel weakened, although the difference in cultivation rank or battle prowess can partially offset this weakness.
Bloodline Enforcement happens when a team of soul masters fights together, and the soul master with the stronger bloodline can boost the one with the weaker bloodline.
Blood Core - a core that naturally forms during the cultivation of organisms with a sufficiently high concentration of blood essence. The purity of the Blood Core depends on the purity of the bloodline. Unlike standard soul cores, the Blood Core does not adhere to their rules but gradually restores blood essence over time. Additionally, due to its source, this soul core can aid in evolving both the possessor's physique and spiritual realm. An additional effect of the Blood Core was the removal of the need for sustenance for an extended period of time