The outer layers kept on growing in size and expand since the darkness in all the previous ones had reached a level of density that the gravitational pull couldn't surpass with its current power.
Yet, the traction force kept on increasing as more energy amassed there, and the most inner layers slowly started to reach higher levels of density.
As the density increased, even the gravitational pull became stronger. It was a continuous cycle that would continue as long as Noah continued to provide the raw materials needed by the fusion.
June sent him a mental message at some point, and Noah listened to it right away since the procedure didn't keep him too busy. "The "Breath" is acting funny out here. It has started to converge toward the underground area since a while ago."
She was still pissed that Noah had prevented her from joining the experiment, but she wouldn't fail to inform him about the consequences that the procedure was creating in the outside world. After all, Noah had been locked up inside his training area for almost a day by then. She was worried about his well-being.
Noah told her that he was fine, but he didn't add any other detail. That wasn't the time to let his mind wander through his feelings for June. He had to remain focused even if he only needed to pour more darkness in the environment to keep the fusion going.
The massive sphere would become smaller every time the density in the inner layers increased. Still, that only enhanced its gravitational pull that made more "Breath" gather to form new outer layers.
Noah almost felt in awe as he sensed those events unfolding right in front of him. The vast mass of darkness had a shape similar to the stars that he had seen in pictures in his previous world, and it was a fantastic sight even if he could only analyze it with his mental energy.
Yet, the first issue eventually appeared.
There were often flares rising from the surface of his sphere every time the density increased. They weren't a problem before since they were too weak to cause any damage, but it had reached the point when Noah felt forced to take even more steps back.
The release of energy was a good thing though. According to Noah's memories, elements would release energy only when they fused, which meant that something was happening in the inner layers.
Everything continued in that way during the entirety of the following day too, and Noah only had to keep darkness inside the underground area in that period. The cycle of shrinking and enlarging continued without any problem, and it was slowly leading to the point where a significant change was bound to happen.
The Black Hole spell had stopped working by then, and the sphere had become entirely self-sufficient. Only an external influence or the lack of energy to gather could prevent it from growing further.
Something happened during the third day since the beginning of the procedure.
Noah was pouring darkness in the environment as usual when the sphere suddenly shrunk until it was a little orb once again. The gravitational pull that came from that new form was even far stronger since most of the "Breath" in the environment started to gather there and create more layers.
'It's happening,' Noah thought as a smile appeared on his face.
The only thing that could make the gravity spike so much was the appearance of a heavier element, or, in his case, it meant that his darkness was finally transforming into a higher form of energy.
Noah analyzed the inner layers. There were minute trails of dense gas at the center of the sphere that was far darker than the other surrounding it.
When it came to higher energies, evaluating their power was quite complicated. For example, June's black sparks still belonged to the power level of a cultivator in the gaseous stage, but their actual prowess could surpass those limits.
The "Breath" and the higher energy were different both in shape and power that they were capable of releasing. No one had even created clear labels either since less of a handful of people knew about the existence of higher energies.
Noah found himself in that spot now. He had a form of higher energy right in front of him, but he couldn't evaluate how strong it was. He only knew that it was powerful thanks to his instincts.
However, those minute strands of thick dark gas were the best result that he had obtained in more than two decades. They were energy on a higher level than his darkness, and they had formed through a procedure that just altered their environment.
They had come to life naturally. Noah had just prepared the area for the procedure and set it off.
Noah didn't know if that was the final form that his darkness could reach, so he let the procedure going to see if he could strive for energy even higher than that one.
The gravitational pull had started to affect the entirety of the underground area, and all the "Breath" inside it rotated around the black sphere. Noah had to pour a lot of darkness back in the air to keep up with that consumption, but its sight was terrific.
It was as if Noah was in front of a real star, only black in color.
June sent him another mental message at that point, but Noah ignored it. His focus had to be on the procedure since it had just chosen to form higher energy.
The sphere enlarged and took the "Breath" still lingering in the outer layers. It was devouring everything that entered in its gravitational pull and built layers over layers made of energy.
The quantity of higher energy kept on increasing too, which made Noah eager to see what would happen if all that "Breath" reached that higher form.
Yet, June sent another message, and Noah understood that the situation had to be troublesome since she knew that he was focused on the experiments.
"There are major repercussions here!" June said in her mental message. "The "Breath" is gathering toward you, and some of the weaker buildings can't handle this suction force."
Noah knew that stopping there was the right move. After all, he had already obtained what he wanted.
The procedure worked, but he had to perform it in a different environment. Divine Market city didn't allow him to go all out with his recklessness, and he would destroy some of the buildings in if he lost control after deciding to keep going.
The mass of gas soon reached the inscribed walls and continued to grow. It had come to a point where even Noah was struggling to refill the darkness in the environment.
However, that wasn't inherently a bad thing. It only meant that nuclear fusion worked.
Now, his focus was on finding if that was the limit of the higher energy and invent procedures that would allow him to seize it.