During the Martial Soul Awakening Ceremony, those who have two Martial Souls are known as having Twin Martial Souls or Twin Spirits. People with Twin Martial Souls usually have Innate Full Soul Power. The inheritance of martial souls generally comes from the parents. Generally speaking, the inheritance of martial souls is inherited from the relatively stronger parent. But when the strength of the martial souls of the parents is almost the same, or even the same, it is randomly selected to inherit, and in this case, it is more likely to have a martial soul mutation and also a chance of twin martial souls.
The reason why there are so few people with twin martial souls is that the preconditions are harsh. This is how it is recorded in the materials of the Martial Soul Hall. There are two main prerequisites for the emergence of twin martial souls. First, the martial souls of both parents must not be the same. The farther the difference, the greater the probability of producing twin martial souls. At the same time, the closer the quality of the martial souls of both sides, the greater the probability of producing twin martial souls. That is to say, if there is a gap in the quality of the martial souls of the two sides, it is impossible for children with twin martial souls to appear. Even if these two premises are met, the possibility of producing the descendants of twin martial souls is only one in a thousand, or even one in ten thousand.
It is a rare ability that most people don't have. With Twin Martial Souls, the soul master can have 18 soul rings, nine per martial soul, and 19 if they become god. Which is still something that has only ever occurred twice.