Recommendation ticket, please.
The level of Innate Soul Power determined the strength of Soul Power Affinity. This was reflected not only in cultivation speed; more importantly, it affected the Cultivation Upper Limit.
The core rule was this: the "High-Speed Interval" of cultivation speed covered Soul Power Levels below the value of one's Innate Soul Power × 10.
For example:
Barton's Innate Soul Power was Level Seven, so he could maintain a relatively fast speed through the Soul Saint Stage—the seventh rank of soul masters, not counting Soul Scholars—but after advancing to Soul Douluo, it dropped sharply.
By the same logic, a soul master with an Innate Soul Power level of six could maintain high speed through the Soul Emperor Stage and below.
As for soul masters with Innate Ninth Grade, their speed in the ordinary Titled Douluo Stage was not slow, only easing off once they reached the Super Douluo Stage. Those with Innate Level Ten, because the breadth of their martial soul was complete, had an even greater advantage in comprehending artistic conception at the Super Douluo Stage.
Within the same rank, different levels of Innate Soul Power did still affect cultivation speed, but they were far better than being in the next lower tier. For instance, in the Soul Emperor Stage, Bao Ruoxi had an Innate Soul Power level of 6.2, so the decline in her cultivation speed was far slower than someone at level 5.8.
Therefore, in the lower stages, those with weaker aptitude could use resources to catch up to those with stronger aptitude. But at the Soul Saint and Soul Douluo Stages, high-grade resources became scarce while the difficulty of advancement kept increasing, causing overall speed to slow drastically across the board.
Members of the Chen family Main Lineage basically had Innate Soul Power