For example, if one secret art increased the knight's strength and agility but the new one was increasing dexterity and endurance, then that chance of one being able to successfully switching to the new art was less than 10 percent.
The Bloody Slaughter Secret Art focused on strength and perception, which were a rare combination. That was why, if Karl wanted to reach the higher levels as a Knight, the benefit that Weiss was planning to give him was essential for him.
But as the deterioration of the mind was a fundamental part of this technique, currently even Weiss was not able to completely great rid of it.
Maybe she would be able to do something like that in the future after reading and learning about more secret arts, but for the time being, Weiss was limited to what she could do.
But that did not mean she was completely powerless. She could still lessen the mental deterioration so that even in high levels, Karl would not completely lose his mind.
For the time being, doing so was Weiss's target.
So with this objective in mind, she again focused on the book. She was planning to find an useful solution before going back to the cave tomorrow, so there was no time to waste for her.
...
While being trapped inside the dimly lit cave, Karl was thinking about his future. The story he was telling to Weiss was not a lie but his true life story.
After being treated as a trash by his family, he focused on his training and managed to become a knight before any of his other siblings.
The "Bloody Slaughter Secret Art" was something that he had found in an abandoned house where he was staying during his visit to a dangerous forest to hunt a beast.
After finding this secret art, he had immediately noticed that the quality of this secret art was higher than the one that his family had.
But at the same time, he had also noticed the dangers associated with it. The Bloody Slaughter Secret Art hadn't really tried to hide it's dangers from it's users.
But still, after thinking for just a few minutes, he had decided to change his knight's path to this new secret art.
It was difficult for an official knight to change their secret art after they had already condensed their core. But an apprentice knight did not suffer from this limitation.
They were capable of changing their secret arts as many time as they wanted before they had started their core formation process.
But then they also needed to start their training and life force control from the very beginning again and as that was a very time consuming thing to do, no one would do it very often.
After changing to the Bloody Slaughter Secret Art, Karl's growth speed increased by a lot and he also became almost invincible in his own realm. At least in front of his siblings and her father's subordinates.
This was a clear proof of the superior quality of the Bloody Slaughter Secret Art. And Karl was relieved that he had made the right call.
With this secret art, he managed to condense his life core and became a official knight at a very young age of 23. That was actually a better result than many well known geniuses and his whole family was extremely surprised by this.
There were quite a few retainers of the house who had started to support him as the future successor after this.
They were even dreaming for him to reach the mid or even the high level as a knight in the future. They were all sure that Karl would be the perfect successor.
But as his father was still perfectly fine, there was no conversation about him taking over anytime soon.
Even though quite a few members of the family were happy about his sudden growth and about their family now having two knights, his father was not one of such people.
He remembered the way he had treated this son of his so he was sure that Karl had held a grudge against him about this matter.
This made the baron fearful that this son who had now became a powerful knight, would try to kill him in order to become the next baron soon.
With this thought in mind, the baron made a decision to get rid of the trouble before it was too late.
But even though Karl had just reached the offical knight realm, he was not much weaker than his father in terms of strength.
That was why the baron was not confident in defeating and killing Karl in direct combat.
So he could only use crafty methods to deal with him and the method he ended up choosing was the same as the one that Karl's future mistress utilised, poison.
One day while having tea, Karl's suddenly paused and his suppressed killing intent suddenly overflowed.
With his strong perception and ability to sense killing intent, Karl was actually able to sense the presence of a killing force in the tea that he was drinking.
This tea was made by his favourite maid of the family and one of the few people whom he really liked.
So this betrayal made Karl extremely angry. And with his anger rising, he was unable to continue suppressing the killing intent in his heart.
...
That day, a tragedy had fallen on the baron family of Dummer. This noble family was in a rise with one of the current baron's son becoming an official knight at a very young age.
Many other families had guessed that with such a talented young generation, the Dummer family even had a chance of advancing in the future and becoming a viscount family.
But then suddenly in one single night, both of their official knights suddenly disappeared. At that same time, all the people living in the baron's castle were also killed.
Most mysteriously, everything had happened extremely quickly and when the other people had realised that their was something wrong and had came to check, they found only a dead body filled castle without any living beings in it.
...
What had happened in the castle was quite simple actually. After getting super angry, Karl had lost himself in his anger and resentment. So when his killing intent had fully erupted, he had lost his mind.
When he had came back to his senses, he had found that all the people of the castle were already dead and he was holding his father's head and a blood stained sword in his hand.
Karl had immediately realised that it was him who was responsible for all the murder around him.