Fusing with a ten-thousand-year Soul Spirit was effortless for Lu Yi, who had done it many times before.
During the Soul Spirit Ritual, he assessed Zhou Sichen's condition and sealed away four to five thousand years' worth of the Hurricane Falcon's Soul Power.
That Soul Power would gradually be released as Zhou Sichen cultivated. It would speed up his cultivation to some extent, but more importantly, it would restore the Soul Spirit's original strength.
Once the sealed Soul Power had been fully released, the Soul Spirit could begin growing alongside Zhou Sichen's cultivation.
Unfortunately, Soul Beasts cultivated in a completely different way from humans. After becoming Soul Spirits, they made poor use of the Soul Power cultivated by Soul Masters. Even great intelligence could hardly speed up the process.
Of course, it was slow only by human standards.
After all, humans lived nowhere near as long as Soul Beasts, yet grew more than a thousand times faster.
In this era, a gifted human could commonly become a Titled Douluo in their forties or fifties, gaining strength to rival a Hundred-Thousand-Year Soul Beast.
A Soul Master might cultivate for ten years while his Soul Spirit gained several hundred, or even a thousand, years of cultivation.
But for a high-level Soul Master who already had Ten Thousand Year Soul Rings, increasing the ages of his Soul Rings and Soul Spirit offered limited benefits. At most, it would make his first few Soul Rings look better.
If a Soul Master hit a bottleneck he could not break through, however, his continued cultivation would still help his Soul Spirit grow.
With luck, a breakthrough in the Soul Spirit's cultivation—past ten thousand years or a hundred thousand years, for example—might in turn help the Soul Master break through that stubborn bottleneck.
This was no impossible