Despite being a mere yellow soul ring, the Void Throne's first soul ring was an indubitable million-year soul ring. And with such distinction, came four abilities.
The first is simply called Edict, an enforcement of law upon all who tread within the Empyrean's domain.
Naturally, this was not without limits.
It all depended on the target's mental power and soul power as to whether they could resist the Edict.
But if there is such an overwhelming difference between Caelum and his targets, then they might not even be able to resist at all.
He could potentially command them to kill themselves and they would. Of course, this is just a theory for now.
The second ability is called Sovereign Presence.
With his mere presence alone, any allies within the Empyrean Domain would be bolstered, gaining 30% increase to strength, speed, defense, soul power and mental power.
This enhancement grows by an additional 30% for every soul ring added to the Void Throne, culminating in a staggering 270% boost to everything. This turns Caelum into both a terrifying controller and support.
The third ability is called Overlord's Hearth. It is meant to be used with the fourth ability called Undying Army.
Overlord's Hearth is an ability that evolved from the sudden mutation that occurred on Caelum's martial soul that went unnoticed when he witnessed his mother die.
The brief flash of light that Celine and Skydream Iceworm saw was, in fact, Grace's soul being absorbed into the throne.
Now, with a proper soul skill to facilitate this absorption, the Void Throne is able to harvest the souls of those who die within the Empyrean Domain. This naturally included the soul beasts whose soul rings were absorbed by the Void Throne.
The souls are then stored within the Throne itself which could be found nestled within Caelum's spiritual sea.
His mother was there, sleeping while being nourished by the Void Throne.
This nourishment is an important aspect of the ability as it ties to the Undying Army.
The souls harvested by the Void Throne can be unleashed as an Undying Army to fight for their Sovereign, benefitting from all the boons of his Empyrean Domain and Sovereign Presence.
They could also grow stronger by fighting and devouring each other outside of the passive nourishment of the Void Throne. And thus, in the long run, the Undying Army would not only be numerous but also powerful.
These souls have absolute loyalty to Caelum, their wills completely branded with subservience to the Empyrean. The only exception to this being Grace herself whom Caelum had subconsciously released from his tyrannical control.
Naturally, there are also limitations to the Undying Army.
In order to summon his army, Caelum would have to bear the weight of their presence with his mind, meaning he could only summon a limited number of them at a time, depending on their strengths.
And thus he is faced with a choice.
He could either unleash hundreds of weak soldiers or a handful of elites. It would all depend on him.
However, each death of a summoned soul would consume his own mental power, something that he would have to manage well.
Moving on to his external soul bone, perhaps due to Caelum's subconscious desire, it had shaped itself into a simple white-gold crown seemingly made of frozen silk.
And much like his soul ring, this soul bone gave him four abilities.
The first two were another paired abilities called Spiritual Detection and Spiritual Sharing.
The first gives him a sort of omniscient perspective over everything around him within a limited range dictated by his mental power while the second allows him to connect to the minds of his allies to share, not just his vision, but also his thoughts.
In a way, Spiritual Sharing turns him into the core of a hive mind.
The third ability called Mental Projection is another control ability that could be used in various ways.
This ability allows Caelum to project upon the physical world an image of what his mind conjures. It is basically an illusion ability that could be used to hide soul rings or control the battlefield.
There are many other ways to use it, but Caelum would have to figure it out himself.
His imagination is quite literally the limit.
And finally, his fourth soul bone ability and technically his first actual offensive ability—Mental Syphon, allows Caelum to drain a target's mental power.
The speed of the drain depends on the difference between his own mental power and the target's.
This means that if the target has a much stronger mind than him, he might be in trouble. But likewise, if the target's mind is weaker, he could drain them until they faint.
And the more mental power he drains from the target, the faster the drain gets.
This is a very powerful, if sinister, ability. The only real downside to it is that he does not get to keep a hundred percent of the mental power he drains.
He would need to refine this mental power and purify it before he could fully absorb it as his own to further strengthen his mind.
Still, this is an invaluable treasure because, compared to soul power that could be cultivated much easily, mental power is incredibly difficult to grow. At least, now he has a reliable way to do so.
With all this, Caelum was a little more confident in surviving now.
But at the same time, he knew this was not the end. He had to keep moving and keep getting stronger.
Even now, he felt his soul power was still stuck.
Although it had already settled within the pool, there was still something blocking it, preventing it from expanding further.
And there was also Celine. They had to find a suitable soul beast for her.
As he opened his eyes, he heard a voice in his head, calm and humble.
'Master, I sense a tremendous amount of life force within your sister. Her martial soul must have a powerful life attribute. I know where we can find one that might suit her well.'
Caelum was initially surprised that Skydream Iceworm was calling him Master, but he realised this was because of his Empyrean Domain and his Void Throne's Overlord's Hearth which demanded absolute loyalty and obedience from his harvested souls.
From now on, he would have to get used to this new reality. But for now, he needed to hear what Skydream had to say.
"Tell me."
'When I was still trapped in the core area of Star Dou Forest, I overheard some of the soul beasts talking about a hundred thousand-year-old Blue Silver Emperor who sacrificed itself to a human. It was because of that news that I began plotting to create a god.'
"Why are you telling me this? That soul beast is already dead."
'No, Master. The Blue Silver Emperor is the ruler of all Blue Silver Grass. It is basically their progenitor. And just like the rest of its kin, it would not die easily even if it sacrificed itself. I believe it left behind a seed for its rebirth.'
"That's a hundred thousand-year-old soul beast. My sister wouldn't be able to handle its power. Without you sealing yours, I would've died already. How do you expect her to absorb it even if we find it?"
'If its current state is as I expect, then its mental power would be that of a newborn infant human with only its instincts driving it. With your abilities, you could easily suppress it and force it to sacrifice itself to your sister in the same way I did.'
"Fine. We'll discuss it later, but are you sure you can find it?"
'Yes, Master. But it's not me who will find it. It's you.'