Much like the soul crystals, the different factions out there in the cosmos - or wherever else they came from – had different names for pretty much the same thing. There were different stages of power one went through when that someone started strengthening himself or herself with soul power.

Depending on who you heard it from, the first step could be called the Body Strengthening stage, Vessel Refining stage, Perfecting Body stage, which were just a few among many other names with different combinations of words that, in truth, referred to the very same thing.

In practical terms, this step consisted in empowering his or her physical body – which would make them overall stronger, faster and deadlier than normal – as well as correct its ‘flaws’.

That was where Danny’s feeling of reinvigoration, of refreshment, came from each time he consumed the shiny stones. The energy contained within the small gems was not just improving his physique in the practical sense, but was also ‘mending the cracks’ in his body, so to speak. It was perfecting his body’s ability to contain soul power.

That was why some called this stage the Vessel Refining or Vessel Perfecting stage - you were basically adapting your body to better interact with soul energy and contain it.

The existence of those ‘cracks’ or ‘flaws’ also explained a lot of things that remained a mystery until now. For example, it explained why zombies did not attack one another and sought to kill the living.

Both beings - humans and zombies - had some form of soul power within them. Zombies had the crystals lodged in their brains and humans had their connection with the astral dimension that drew soul power to Earth.

In that case, then why the simple-minded undead only attacked their living counterparts instead of indiscriminately fighting anything that moved? If the reason behind their unbridled aggression was an unending hunger for more of the metaphysical energy, why didn’t they fight each other out?

It was very simple actually.

The soul power within the walking corpses did not emanate outside. It was perfectly confined within its meaty prison.

The crystalized form that soul power assumed once the link between dimensions was broken – basically whenever someone died – and the energy found itself trapped on this side was static. It did not ‘spill’, for the lack of a better word, to the outside. Therefore, zombies could not perceive it.

In other words, and simpler terms, zombies were freaking dumb.

There was no code of honor among them that stopped one undead from killing the other. No. The only thing that prevented every horde, every gathering of zombies from becoming a huge free-for-all melee/buffet was their own inability to understand that each and every one of the walking corpses similar to themselves also carried soul power within them.

Stupidity and simple-mindedness were responsible for the peaceful coexistence among zombies.

On the other hand, we had living and breathing human beings, which were filled with soul power coursing within them in its ethereal state. In this form, soul power was not very useful for the common mortal like Danny, as it did not interact with matter the same way its crystalized form did.

In fact, with only mundane means available to him – originating from Earth’s not at all magical society – Danny had no way of harvesting its power. He couldn’t even direct or properly interact with it, rendering all of that ethereal energy useless to both him and the common human being surviving out there alike.

Worse yet, soul power in its ethereal shape moved around, flowing through one’s body unimpeded by flesh or blood. It wasn’t stationary like it was in its crystalized state. This wouldn’t be necessarily a bad thing if not for the ravenous undead.

Danny was no expert on the subject – and he doubted even Tutu fully comprehended the laws under which the magical substance operated. Maybe not even the highest and most influential powers behind the invading forces could answer some of his questions.

Even so, from what he could understand, for some reason, the mist-like soul power overflowed from its original dimension through the link connecting both planes of existence within sentient beings.

From this point of entry, the ethereal substance slowly dispersed.

Even though most of it flowed in a contained manner within the body of the person hosting the link – as both humankind and other sentient beings had a somewhat natural ability to restrict and draw the intangible substance within them –, some of it still seeped through the ‘cracks’ and ‘flaws’ in that person’s body, being released into the surroundings.

And therein lied the problem.

The ‘spillage’ of soul power formed something akin to an aura that surrounded the person, and it was this very same aura that was perceptible to zombies.

Danny did not know how the unthinking creatures could instinctively recognize said aura, and Tutu had not clarified it to him either. Still, even if he could not exactly explain the reason behind it, knowing why zombies were attracted to living beings was already a great discovery.

Once one understood the underlying truths behind any given phenomena, one could start working to exploit it to his or her advantage. Knowing why zombies were drawn to the living could be the key that allowed humankind to completely overcome the undead menace in the future!

‘If I can prevent the soul power within me from leaking or withdraw my aura somehow, then I would be invisible to the zombies…’ Danny thought with some excitement.

If he really managed to do that, dealing with the undead would become a mere child’s play. He would be able to straight up walk to them and smack the creatures to death with no reprisal whatsoever. All that danger he faced when he dealt with the horde at the factory could be avoided.

However, his eagerness was soon quenched by a dose of reality, the smile that hung on his face replaced by a more serious and pensive visage. He was still a far ways from turning his ideas into reality. In the end, it all came back to the fact that he neither had the means or knowledge necessary to take advantage of this new information.

At the moment, Danny had no way of influencing or commanding the soul power within him. All that power coursing through him, all that energy… and he could not leverage it. In this aspect, he was not any different from any other human survivor out there.

Even though he knew there were ways out there for someone like him – someone in the Body Refining stage – to control soul power, as Tutu had already revealed as much, the demon obviously would not grace him with such valuable means or teach him those techniques for free.

Still, everything he had learned last night had been a nice step forward and he had already gotten more from Tutu than what he was initially expecting to be honest.

He could not be too greedy.

After all, now he could point where he stood and could name what he was missing and what his next steps would be at the very least.

Coming back to the matter of his own personal progress and the stages of power, even if Danny was not aware of what exactly he was doing at the time, by continuously consuming soul crystals every day ever since he learned from Tutu about their existence and uses, he already made quite some inroads into the Body Refining Stage.

He could not be called a mere beginner anymore. He had taken quite a few steps into the path of power already.

Given that the soul gems were plentifully available all around, as everywhere he looked there were zombies waiting to be killed and harvested, and considering that his fellow humans were not competing against him for the valuable crystals just yet, making it so that he had exclusive access to them for now, Danny was like a wolf let loose in the henhouse.

He was not hurting for resources right now, as his bulging pouch containing his stash of the shiny stones could attest to. On the contrary, the speed of his advancement was only limited by how rapidly he could consume the soul gems.

He could not say for sure how far he had come. Though he had developed his strength immensely and had progressed well into the Body Refining stage, he could not effectively measure how much longer this step of power would take, whether it would be days, weeks, months or years.

According to the demon, each person was different so how much time one had to spend at the Body Refining stage varied greatly. Even among individuals of the same species, no two bodies were the same, so there was no way of accurately telling how long it would take Danny to finish mending the ‘cracks’ on his body.

Tutu had also said that, theoretically, there was no limit to how much one could improve their physique and grow their speed, strength and endurance. One could indefinitely remain at the Body Refining stage to hone their physique before moving on if they so wished.

Yet, perfectionism was not the standard way in the multiverse.

Indeed, it was true that there was no theoretical limit to how much one could further the strength and endurance of their own body in the Vessel Refining step. However, there was a catch: after a while, investing resources and soul power while remaining at that first stage rendered increasingly diminishing returns.

Tutu had clearly told him that the more one stuck at one step before moving on to the next, investing more and more resources, the more solid their foundations would be in the future when climbing the peak of power. In other words, the more you spent now, the better your future prospects would be.

Even so, most people across the multiverse did not choose to do so. The matter was not something as simple as better future prospects equaled to better option.

By stalling your progress to perfect your foundations, you would not only be investing resources that would yield more returns if you had already progressed to the next stage, but you would also be limiting your personal power, which was something often frowned upon by most factions out there.

After all, potential was just potential at the end of the day. If the adult snake could kill the baby dragon, what did it matter that the dragon would one day be able to soar through the skies and breathe fire?

Strength was all it mattered. Strength reigned supreme.

The cosmos was not a peaceful place. In fact, the multiverse was a place filled with conflict and disputes for resources. Therefore, choosing to delay your advancement and refuse the immediate boon in power could mean your death when you crossed the path of someone who went for more immediate gains.

Such is the way of the multiverse - the weak became fuel for the path of the strong. Survival of the fittest at its finest. In this aspect, human civilization mirrored the way of the multiverse pretty well even before the Apocalypse happened.

Truly, only influential, powerful and rich factions could afford to nurture the path of their young ones by investing resources into perfecting their foundations. Those sheltered noble scions could count on their predecessors’ protection while they developed themselves, avoiding the bloodshed and strife for resources that often prevailed in the myriad planes that existed out there, taking the easy and highway road to the heavens without any of the difficulties often associated with climbing to the peak of power.

Danny’s case was simpler however.

As an earthling, none of the techniques, methods, skills, manuals and other different ways that improved and controlled the process of progressing from one stage of power to another more efficiently were available to him.

As Tutu had already told him long ago, he could only tread the idiot’s path and keep swallowing crystals like they were candy, inefficiently making use of all that soul power.

At some point, his body should reach some kind of saturation point and he would naturally progress to the Mind Gate stage - which yes, had many other different names as well.

Tutu did not elaborate on what this next stage of power was all about. The only thing Danny managed to pry from the demon’s shape-shifting mouth was that there was no way he would miss it when it eventually happened and that this new stage was fundamentally different from the previous one as it would finally grant Danny the ability to direct and manipulate soul power in its ethereal state.

Though he could not prevent himself from advancing to the next stage when his body reached the so called saturation point that Tutu mentioned - and therefore could not perfect his foundations like the noble version of aliens out there could regardless of how big his hoard of soul crystals was - he did not care all that much about that.

He was beyond eager to reach that threshold and advance to the Mind Gate stage. To be able to tap into that well of power would be incredible. He could not wait to finally see what he could accomplish with the metaphysical energy.

Would he be able to sling spells like a mage? Would he be able to fly? Danny had no idea where the limits lied. He knew that the mysterious energy could become almost anything, so he could not even fathom what he would be able to do with it.

Yet, he was incredibly excited to find out.