There is an optimal age for each Soul Ring bottleneck, which determines the oldest possible Soul Ring that can be absorbed without significant risks.
Soul Masters can naturally absorb younger Soul Rings; however, there have been rare cases of Soul Masters successfully absorbing Soul Rings beyond the optimal age. In normal circumstances, this could lead to severe injuries or even death upon rejection. However, with an exceptional physique, spiritual power, and willpower, the odds of success can improve.
When choosing a Soul Ring, selecting one with a matching attribute is more important than its age. Just because a soul beast is 425 years old doesn't mean you can choose it as your Soul Ring. If your attributes don't match, an agility-type attack Soul Master may end up with defensive soul skills, or a control-type Soul Master may receive support-type buff soul skills. Therefore, attribute compatibility is crucial when selecting soul beasts.
However, if you are choosing a super soul beast as your Soul Ring, you don't have to worry about that, as they always grant super-powerful soul skills. Even if an attack-type Soul Master receives a super-powerful support-type soul skill, so what? Their combat ability will only improve.
Xie Yue knows of more than 20 super soul beasts. Even though he can choose any of them as his Soul Rings, he doesn't want to. He refuses to acquire buff skills, even though they wouldn't weaken his combat power. He wants to become an assassin, so he has already decided which super soul beasts to select. He has carefully considered his options.
Even though he knows about super soul beasts, he can't possibly obtain his first Soul Ring from one, right? He is just a six-year-old kid who has supposedly never read about soul beasts. At least, that's what others believe.
So his first Soul Ring may not be ideal for his needs. Sword Douluo will choose it for him. However, for future Soul Rings, he will be able to select them himself and have others search for them.
Upon hearing the path Xie Yue had chosen, Sword Douluo accepted it after some thought. Some power-attack Soul Masters possess mobility equal to that of agility-attack Soul Masters.
For example, the original Xie Yue was a power-attack Soul Master, yet he had the agility of an agility-type Soul Master. So, even though Xie Yue's approach seemed like cultivating two paths, in reality, he aimed to become an agility-type attack Soul Master—he simply wanted powerful attack skills as well. There was nothing wrong with that. It wasn't as if he were trying to cultivate both support and attack types, which are fundamentally incompatible.
"Okay, then let's go," Sword Douluo said, leading them away.
After some time, a carriage arrived near Sunset Forest. Sunset Forest was extremely secluded, located very close to Heaven Dou City, and home to many dangerous creatures. At its core lay Dugu Bo's medicinal garden and the legendary Ice and Fire Yin Yang Well.
Although it was a large forest, at first glance, it didn't seem much different from the description of Great Star Dou Forest Xie Yue had heard about. However, upon closer examination, the Great Star Dou Forest was described as a tropical rainforest, whereas Sunset Forest had more northern flora. The only similarity was that both forests were covered in Blue Silver Grass.
"Let's go in." After stepping down from the carriage, Sword Douluo picked them up by their hands and vanished.
In the next moment, they appeared at the outer region of Sunset Forest. They moved slowly among the trees. While walking, Sword Douluo taught them essential survival skills, such as forest camping and navigation. He had brought them here not just for hunting but also for training, so they didn't rush to hunt soul beasts.
The following day, they encountered a suitable 390-year-old spiritual-type fox. After subduing it, Sword Douluo handed a dagger to Nana, instructing her to kill it and guiding her through the absorption process.
A short while later, Hu Liena successfully absorbed the Soul Ring and advanced to an 11th-level Soul Master.
Her skill turned out to be a charm-type ability. Since foxes were commonly charm-type soul beasts, finding one wasn't difficult with a Title Douluo's spiritual power. They continued their journey through the outer region.
But then, something unexpected happened...
---
It was the second day of their expedition. As they walked, Xie Yue remained silent, carefully observing every soul beast they encountered.
Although he didn't recognize most of them, he had memorized the description of some of the most powerful soul beasts mentioned in the original books.
Before his death, he had dedicated time to committing them to memory, knowing that the Douluo Continent's First Era lacked knowledge about super soul beasts. If he hadn't memorized them, he might have missed one even if it stood right in front of him.
And now, his painstaking efforts were paying off.
Xie Yue abruptly stopped in his tracks, his mind racing. What could he do now that he had spotted it...? How could he convince Sword Douluo to capture it? Even if Sword Douluo caught it for him, what excuse could he give to justify absorbing its Soul Ring...?
Sigh...
"Grandpa~ That bird looks so beautiful. Can you catch it for me? I want to keep it as a pet," Xie Yue said, feigning innocence after a brief moment of thought.
He pointed toward a large tree, where a simple-looking green bird perched. It appeared unremarkable—only its beak was red. It was roughly the size of two palms. However, this seemingly ordinary bird was actually the most ruthless bird among all avian soul beasts.
Its name was the Emerald Demon Bird.
The Emerald Demon Bird was infamous as one of the most savage avian soul beasts, earning the title of a "fierce bird" in the world of soul beasts. It was a relentless predator, known for killing other soul beasts and consuming their brains. Its growth depended on devouring the brains of living creatures. Both soul beasts and humans were its prey, though it particularly favored human brains.
Wherever Emerald Demon Birds appeared, creatures were left with gaping holes in their heads, their brains missing. Fortunately, these creatures were extremely rare. Human knowledge of them was limited, with only a few references found in ancient records.
It moved as swiftly as lightning and was ranked at the top in terms of speed among all soul beasts. As a wind-attribute soul beast, its incredible velocity was due to its ability to propel itself using wind energy. Not only was it extremely fast, but its attack power was also formidable, specializing in striking the heads of its targets.
It was the nemesis of almost all flying soul beasts. Its explosive bursts of speed and power made it a terrifying predator. While it couldn't match the Azure Peng in long-distance flight, few flying soul beasts could rival it in short-distance bursts.
At 100 years old, it will be merely the size of a palm, but its emerald-green eyes would gleam with a fierce light. By the time it reached 100,000 years, its translucent green form will resemble a jade carving. The bird before Xie Yue was only the size of two palms—meaning it was just 200 years old. But Xie Yue didn't care about that.
"Hmm? I'd advise you, kid, not to think about raising soul beasts. It's better to buy already-tamed ones," Sword Douluo cautioned, knowing that wild soul beasts couldn't be domesticated.
"Grandpa~ It's just a tiny bird. What harm could it possibly do to me? I'll keep it locked in an iron cage when we get home. That should be fine, right?" Xie Yue pleaded sweetly.
Meanwhile, Xie Yue closely observed the bird's behavior. If it took flight, Sword Douluo would immediately recognize its extraordinary nature. But the bird remained motionless, as if nothing had happened.
That little Emerald Demon Bird wasn't the least bit concerned. In its eyes, the three before it were just two weak Soul Masters and an old man without soul power. Sword Douluo had suppressed his aura upon entering the outer region, only releasing it when necessary. Because of this, the bird had no idea just how powerful he truly was.