The two-year plan Gru had drawn up had to be followed strictly. Nothing else was much of a problem; Leo barely even felt the intensity. The only exception was sparring with Gru for one-fifth of every day-six hours by Earth's reckoning.
It was inhuman torture. For six hours straight, he did nothing but take a beating, pummeled by Gru like a punching bag.
Gru lived up to his standing as a level two body refinement wizard. He measured his blows with extreme precision, ensuring that every inch of Leo's flesh received an even pounding, training him as much as possible without inflicting serious injuries beyond what he could endure.
For Leo, this was a truly rare opportunity. Wizard apprentices outside the great families had no chance of receiving such treatment. Having a level two body refinement wizard spar with him every day-what an extravagance that was.
But that did not stop it from really hurting.
The pain made him wish he were dead. He had no chance to fight back. Forget fighting back-he could not even keep up with Gru's movements.
Gru's grasp of openings in battle surpassed Leo's imagination. He could ensure that every attack exceeded Leo's limits by just a little.
Yet that tiny margin was more than Leo could withstand. Countless times, he struggled and squeezed every ounce of strength from his body to overcome that tiny margin, only to end up crushed by just a little again.
It was a psychological tactic that kept Leo from ever seeing any hope of victory.
Gru paid no attention to Leo's cries of pain or pleas for mercy. He beat him for a fifth of the day without wasting a moment.
With triple gravity weighing on him, every movement cost Leo several times the strength, and his heavy body suffered Gru's merciless onslaught.
With Gru on the outside and triple gravity pressing down within, Leo felt like a stubborn rock in a steel furnace, being hammered like mad.
Along with the pain, he could also feel his body improving.
"Come on."
Leo growled, his face contorted. The shadow beneath his feet churned and twisted, spreading upward from his feet across his entire body.
His heavy body seemed to fill with strength. The effects of triple gravity weakened, his mana circulated faster, and the feeling of power returned!
Facing Gru's heavy punch, Leo raised both hands to block.
Bam!
His entire body spun through the air, but he could clearly feel that the pain had decreased by half.
"??"
Gru, who should have pursued him and continued the relentless beating, hesitated. He tightened his fist. The impact had felt wrong. A single glance at Leo revealed the problem.
His aura was wrong.
"Kid, I suggest you put away that shadow power, or I'll only hit you harder."
"Don't try any tricks. This is all for your own good."
"..."
Leo did not dare refuse. He had only wanted to see whether shadow power could reduce gravity's suppression and whether it showed any special effects when he took damage. More than that, he wanted to test his shadow talent's abilities in actual combat. He had not expected Gru to see through him at a glance.
Still, Leo had obtained preliminary answers to what he wanted to know.
"Understood."
Leo disdained to explain. He dismissed his shadow power, and triple gravity bore down on him again, slowing the circulation of his mana.
He roared and hurled himself at Gru, only to be sent flying again.
"Leo, you go through so much torture every day. I think you'd be better off cultivating shadow power the way I told you. You could advance just the same. Why make yourself suffer?"
Benji had tried to persuade Leo more than once. Leo possessed shadow origin power that even he envied. As long as he cultivated step by step, he could advance just the same.
In Benji's world, Leo would have broken through his bottleneck long ago. He would never have ended up like this, his strength barely improving and all his talent going to waste.
As Benji saw it, what Leo was doing now was nothing but making himself suffer.
Leo did not answer and kept busy with his own work.
Time was too tight. Every day was packed full. There was neither any need nor any time to explain things to Benji. Beings from other worlds had difficulty understanding wizards' behavior. They were a bunch of madmen who pursued the utmost limits.
Faced with a packed training schedule, Leo could only squeeze out time to carry out his experiments.
First came finding the optimal toxin mixture for his body. Although he lacked a precision laboratory to measure the data, his shadow power allowed him to adjust the toxin ratios as needed, widening his margin for error and roughly identifying the optimal range.
But this required a great deal of time, testing bit by bit.
Different kinds of toxins, mixed toxins-even though Leo could currently only purchase a few selected types, experimenting with them still required a great deal of time.
He had to test how each toxin stimulated his body at different concentrations, as well as how mixtures of different toxins stimulated it at different concentrations and under different conditions.
This seemed like an experiment with a simple principle and merely a complicated process, but its results would remain relevant throughout his entire career as a wizard.
No matter what level Leo advanced to, he would need to use the toxicity of poisons to stimulate his body.
Now was the time to lay the groundwork. The degree to which different toxins stimulated his body might seem similar, but even a difference of only 0.5% would become a terrifying figure when stretched over hundreds or thousands of years.
He could not shorten the other training Gru had arranged, so he could only squeeze time out of the fifth of each day allotted to rest and sleep. That was the only time Leo could arrange freely.
Recalling the ill-intentioned smile Gru had worn while drawing up his training schedule, Leo understood that Gru had arranged it this way on purpose, forcing him to cut into his rest time and preventing him from stopping to rest.
Leo had clearly shown a preference for elemental wizards over body refinement wizards. Gru used this little trick to make Leo miserable, declaring his disdain for elemental wizards.
"Petty man."
Leo took out his experiment log and raced against time to record the changes in his body. With the foundation he had built in Gavarci's laboratory, he easily began his first toxicity experiment on himself.
As the toxin entered his body, Leo could clearly feel both pain and renewal in his flesh. Large numbers of cells died, then stronger cells were born. In their struggle against the toxin, his cells were rapidly replacing themselves.
Different types of toxins stimulated the body differently, and the degree of stimulation also varied among cells with different functions.
The human body was an extremely complex operating system. Although his knowledge from Earth had given Leo an excellent starting point, many bodies of knowledge still needed to be reexamined and reorganized to reach a deeper understanding.
After all, Leo's current body was no longer the frail human body he had possessed on Earth. It was an enhanced body suffused with shadow power.
Much of his knowledge needed reshuffling so that he could better change his ingrained patterns of thought.
Of course, at Leo's current level, any talk of deep understanding was premature. He could only develop and apply what little knowledge he possessed.
His current toxin experiments were just that: crude, passive experiments, with nothing sophisticated about them.
This was an experimental project every wizard carried out, and one of the few for which all the knowledge was publicly available.
The difference was that wealthy body refinement wizards could hire professional elemental wizards to tailor it for them, saving time and effort.
Those without money could only experiment on their own bodies and settle for a vague feeling that it was good enough.
Leo had neither money nor people, yet he wanted as much precision as possible. His only option was to pay in time, experimenting without sleep or rest.
Fortunately, his ten years of experience as experimental material had given Leo an extraordinary understanding of his own body, an advantage in experimentation that others could not match.
He had little free time to begin with, and this project alone consumed a large amount of his rest time. Leo also had to research shadow power, another vast experimental undertaking bound to take centuries. With limited methods and no experimental equipment available at present, he could only construct an experimental framework in his mind based on some of Benji's accounts.
Then he combined it with actual combat, constantly testing his conjectures to lay a good foundation for precise experiments in the future.
With these two major experimental projects arranged, Leo effectively had no time left to sleep. He was busy every day and even had to squeeze in time to eat.
So much so that Leo simply used nutrient solution as his meals, finishing his food in a few seconds and putting all the time he saved into experiments.
These things might seem like a complete waste of time, bringing no increase in his strength. Even decades might pass without any visible growth in strength.
But only Leo himself knew that every experiment he conducted, every conjecture, and every piece of experimental data held extraordinary significance.
Once the experiments finally yielded results, however, that would surely be the moment Leo broke out of his cocoon and became a butterfly.
"Hmph. Hurry up and come out for your beating."
Seeing Leo constantly at work, with all manner of bottles, jars, and experimental equipment filling his room, made Gru furious.
Whenever that happened, Leo received a somewhat harsher beating.
Time seemed to go into overdrive. Leo felt as though he had only just worked out the optimal protocol for his single-toxin experiments, narrowing the margin of error for the optimal toxin to around 5%, when two years had passed.
In those two years, apart from adapting to triple gravity, he had successfully completed the optimal protocol for his single-toxin experiments. As for mixed toxins and conjectures about shadow energy, those had only just begun.
"Kid, come on. We're going to earn some extra money."
Gru's booming voice always rang out while Leo was conducting experiments. Leo knew perfectly well that he did it on purpose, but he could only grit his teeth and endure it.
"Teacher Gru, have you picked a mission?"
As far back as twelve years ago, Gru had been loudly declaring that once Leo adapted to triple gravity, he would take him on missions.
A month ago, Leo had become capable of reliably delivering 200 points of attack power under triple gravity. Since then, Gru had gone out every day to look for a suitable mission.
"I have. Three thousand li from the Purple Flame Wizard Academy, there's a new city called Tiyama, built less than a hundred years ago. The Purple Flame Wizard Academy needs a wizard to guard it. The mission lasts twenty years. This is a high-paying mission I snatched from a bunch of elemental wizards."
Gru spoke excitedly. Beating a group of elemental wizards was an extremely glorious achievement to him.
"I remember that when missions like this are settled, they assess the population, average household income, and the training of wizard apprentices. It's easy to earn a substantial bonus."
"Normally, plenty of official wizards fight over missions like this. But in the vast majority of cases, these missions never become publicly available. They're all taken internally."
Leo looked at Gru and asked calmly, "Teacher Gru, have you overlooked something, or forgotten something? I don't think this mission is that simple, is it?"
"Uh..."
Gru froze at his words, then laughed without a care. "Who cares whether it's simple? We've already accepted the mission, and we can't back out. Let's get there first."
Leo stared straight at Gru, trying to see whether he was hiding anything from him. He was already very familiar with some of these tricks.
Bam!
Leo did not receive the answer he wanted. What he received was an iron fist coming straight at his face. With one punch, Gru blasted him back into his room.
"Kid, don't look at me with that ridiculous gaze. You have no right to resist. We leave tomorrow morning. You have only one day to prepare."
Leo activated the healing rune array on his chest and expertly removed the bruises from his face. Gru's attitude was already perfectly clear. There was definitely something wrong with this mission.
"Yes, Teacher Gru."
Once something had been decided, no matter how many questions Leo had, he could only keep them to himself. He did not currently possess the strength to change anything.
He knew perfectly well that there must be more to this mission than met the eye, but with Gru refusing to speak, Leo had no way to investigate.
"A twenty-year mission. I'll need some basic experimental equipment and a large amount of basic materials. All of that needs to be prepared. Fortunately, I made preparations early, so I won't be scrambling."
"Commoners' towns rarely have materials wizards need, and there's nowhere to replenish them. Bringing more can't hurt."
Leo calculated the wizard coins in his shadow space. He had finally managed to save four hundred thousand, originally intended for setting up a small laboratory of his own.
Now, it seemed that many of his plans would have to be brought forward.
Green Cottage.
When the plump Toronto saw Leo, he greeted him with more warmth than he would his own father.
"Master Leo, you've finally come! I've just received quite a few fine materials. Would you like to take a look?"
"Manager Toronto, please don't call me that. I'm not worthy of it yet."
Ever since Toronto had learned that Leo was selling his own potions to the Purple Golden Flower, he had nearly ground his teeth to pieces in regret.
The potions Leo could make were indeed low-level, but potions were always in demand. No matter what kind they were, there was no worry about selling them.
He had established a relationship with Leo first, yet that fellow Skye had swooped in and stolen him away.
How could Toronto not be angry? He was practically bursting with rage. He tried every possible means of drawing Leo into his shop, using methods so low that Leo was left utterly speechless.
"You may not be now, but you certainly will be. I have faith in you."
Toronto smiled ingratiatingly, utterly unconcerned that he had bestowed an official wizard's title upon Leo.
Leo did not correct Toronto's mistake either. "Have you found the things and people I wanted?"
Since he had known for some time that he would be going out on a mission, Leo had begun preparing several months earlier. Through Toronto and Skye, he had secretly made several sets of preparations.