The cold wind howled through the mountains, spreading the icy chill along the valleys, even frightening the residents at the foot of the mountain.

But when passing by the castle in front of me, all the coldness became calm like a tamed beast.

Keer Siren, the headquarters of the Griffin School witchers.

Not long ago, this place was a dilapidated ruin. Less than one-tenth of the huge building complex had been cleared, and even fewer areas had been repaired and made usable.

But ever since Ciri made a wish to the elves, this place seemed to have reversed the direction of time and regained its vitality.

The four groups of witchers, wolf, snake, cat and bear, are all worldly-wise, but they still look at the magic castle in front of them with amazement.

Relive the glory of the golden age of witchers.

"The Griffin School," Vesemir exclaimed, patting Kelda, who also had white hair beside him.

The old griffin had come back early, and when he saw the brand new castle, he burst into tears in front of Mossack and Geron.

But at this moment, he acted as if the embarrassing thing had never happened, and proudly introduced his home to other fellow demon hunters and juniors.

The door slowly opened, revealing Mossak's tired face.

Mossak, who had just crowned Ciri at the celebration, rushed back to the castle to prepare for the experiment.

He began to explain to the other witchers the subsequent mutation of the witchers.

"This castle is truly amazing." Mossak explained to the crowd, "We are standing on a magical place, and the land is full of magical pulses. Performing a demon hunter mutation here can make our spellcasters' spell intervention more precise and easier."

In terms of fantasy themes, this is a standard paradise.

Vesemir nodded. "Any conditions that can improve mutations are what we should strive for, but—"

Old Wolf showed a nervous look: "Mossak, can you tell us what the current research has reached? Has it really reached - a 100% success rate?"

At the mention of the experiment, Mossak's already excited spirit suddenly began to develop into a frenzy.

He excitedly began to explain his research results to the demon hunters.

"The Demon Hunter mutation is indeed a groundbreaking masterpiece. The more I delve into this research, the more I marvel at Alzu's genius."

"But with all due respect," Mossak shook his head, "today's demon hunters are only half-finished products."

The demon hunters present paused, feeling offended to varying degrees.

"Druids are proficient in biological experiments. When I was young, I also participated in many animal and monster transformation experiments."

"A proper transformation experiment should first create a large number of experimental samples through non-directional mutation, then select the best individuals that best meet the purpose of the experiment for directional breeding, and expand the base number; then select even better individuals from the samples extended from this individual, and repeat the above steps."

"But unfortunately, Alzu's experiment was only halfway through and then discontinued. The Demon Hunter Green Grass Trial is actually the first half of this process: using alchemical potions to destroy the original body structure and reshape a new framework, but the process is uncontrollable."

"It's like opening a 'door' to gain power for all the test subjects, but without a predetermined 'direction' to move forward; as a result, many people ran off the 'road' or 'fell' halfway through the run, which caused a large number of uncontrollable deformed mutations or terminated benign mutations."

Mossak looked at the mutant survivors of the demon hunters in front of him and said, "The survival rate is less than 30%. Not to mention controlling the direction of mutation, this trial actually cannot even control the direction of 'life' and 'death'. It all depends on luck."

The old druid was indignant: "This is not the result of a mature experiment!"

The witchers looked at the old druid who suddenly became scholarly.

Vesemir continued to ask: "So can we control the direction of our progress after 'opening the door'?"

"Of course." Mossak nodded. "Originally, this process should have taken more time. How to choose the path behind the 'door' requires a lot of live experiments. So I changed my idea--"

"Why don't I just follow the current 'path'? Using the current demon hunter as a blueprint, I can set the 'end point' in advance, and the subsequent mutations will go in that 'direction'. This will turn the 'exploration' of crossing the river by feeling the stones into a 'reverse deduction' of filling in the process after getting the answer, and everything will become easier."

"So some time ago I drew a tube of blood from each of you." Mossak looked at the demon hunters who suddenly realized something, "And fortunately, and not surprisingly, I found the demon hunter prototype that is most suitable as the 'end point'."

Everyone looked in the direction the old druid pointed.

Lan raised his chin slightly and smiled shyly and reservedly.

Mossak had already started studying his body a long time ago. At first, it was to check if there were any hidden dangers in the Demon Hunter Trial, and later it was to help Lann adapt to the new power so that he could burst out with the strongest power.

Later, when it was confirmed that Lann was not dangerous and that this body had amazing value... the old druid's scientific research spirit could no longer be suppressed.

Hair, dandruff, nails, and epidermal cells are still relatively restrained.

Blood, small pieces of muscle, and even more embarrassing other body fluids...

It can be said that all the body tissues that could be collected while ensuring Lan's integrity have been collected by Mossack.

That's Mossak. If Alzu were still alive, Lan might have been dissected into pieces by now.

The demon hunters had no objection to the fact that "their bodies were lost to Lann's body".

On the one hand, everyone can see Lann's strength. This guy has been a demon hunter for more than two years, but his combat power has exceeded that of an old warlock over 200 years old. In terms of combat power, this is indeed the best "mutation direction" and the most suitable "end point" for becoming a new demon hunter.

Secondly, Mossak later added that the direction of Lann's mutation was more controllable than that of others.

His "road" is a broad highway, and the experimental subjects will "move forward" in this direction with a little guidance; while others are on narrow paths, which are not only difficult to find, but will also "go astray" if one is not careful.

When Jielong learned the news, he was still very confused. How did he perform the mutation surgery on Lann in the first place?

Am I really that good?

…

The witchers were so happy to have such a good Primarch.

Even a little bit of gloating.

Lambert pretended to shout: "Ah, so Lann will be the 'fixed material' for the Demon Hunter Trial in the future, is that what you mean?"

The witchers couldn't help but burst into laughter.

Lann glanced at Lambert with empty eyes.

Lambert ignored the murderous look in Lane's eyes and slapped his head again.

"What if Lan En gets into an accident in the future? Should we try to collect more of his belongings first, so as to avoid..."

"If you can't speak, then keep quiet!" Lann roared, "Vesemir, take care of your people!"

Looking over again, even the white-haired old wolf was immersed in the joyful atmosphere and had no time to care about his apprentice.

Everyone laughed for a while, but Mossak hadn't finished speaking.

He then dropped another bombshell.

"We all know now that the infertility of a witcher and the infertility of a warlock are two different concepts."

"You are unable to have children because the mutation has caused a species-level gap between you and normal humans. This gap exists not only between you and humans, but also between demon hunters themselves."

"But now the direction of the mutation is controllable, which means..."

The atmosphere in the field was stagnant, and everyone followed the guidance and made guesses about what Mossak would say next.

That's why there was more disbelief in their eyes.

"...That means, in theory, witchers can have offspring with each other." Mossak said with a smile, "Of course, it's between male and female witchers - if we have female witchers in the future."

This news is even more shocking than the increase in the success rate of the Demon Hunter Trial.

When they came to this hypothesis, Mossak and other warlocks were excited for a long time.

However, the demon hunters' reaction to this news was much calmer, at least not as excited as Mossak.

They were all wanderers who lived from day to day and had no desire or urge to have offspring.

At most, it's just curiosity and sighing, and I'm happy that future demon hunters will have one more choice.

"What is the success rate of this?" Reso asked curiously.

Mossak spread his hands and said, "This is just a theoretical hypothesis. I don't have the time or conditions to verify it yet."

The "time" and "conditions" required to verify this theory are indeed quite demanding. The demon hunters fully understood the meaning and laughed evilly.

However, Vesemir heard a different meaning in Mossak's words.

"You haven't verified this 'theory' yet, but have you verified the success rate of the Demon Hunter Trial?" Old Wolf asked hesitantly, "You have conducted human experiments on the Demon Hunter Trial... and were they successful?"

It's no wonder Vesemir asked this question. The old school refused to take in apprentices in order to prevent innocent people from dying because of witchers.

The wolf faction demon hunters all frowned slightly, but the cat faction and snake faction did not react much.

Only the Griffin School and Mossak, who knew the truth, smiled mysteriously.

At this time, everyone had entered the castle's laboratory, and Mossak opened a door.

"Let me introduce you to the number one experimental subject of the Demon Hunter Trial - Leo Bonhart." Mossack showed them the person inside.

The tall and thin bounty hunter was tied to an iron bed, with tubes inserted all over his body, and his hands and feet were bound with thick leather straps and iron chains, and his waist, neck, and legs were also bound.

He looked to be in good physical condition, with his muscles well-maintained, but his spirit was in a state of depression and even collapse.

Hearing the footsteps, he immediately moved the only free part of his body - his eyes - towards the source of the sound.

Mossak pointed at the pair of amber vertical pupils and said, "He killed a member of the Griffin School, Cat School, and Wolf School respectively. Now he can be regarded as atonement for the evil he committed in the past."

"This is another result of the experiment - mutation is not limited to children, but can also be performed on adults. However, since the bones and muscles of adults are already formed, it will be particularly painful to mutate, and the final strengthening effect will be relatively weak."

Mossak commented: "But this also proves our perfect control over the experiment."

All the demon hunters nodded and looked at Bonnard. Even the wolf faction was pleased to use this guy for human experiments, and no longer had any objections.

Crossing the laboratory where "Subject No. 1" was tied up, Mossak explained to everyone Bonnard's future mission. He planned to continue using the bounty hunter's superb swordsmanship to hone future demon hunters, and at the same time, he could also use him as a test subject for future research on the demon hunter's "secondary mutation".

All the demon hunters had no objection and expressed strong expectations for the research on secondary mutations.

Next, it is the laboratory where the real witcher mutation experiment will be conducted.

The figures of the sorceresses caught the witcher's attention.

Triss and Yennefer glanced at the group of men who were chatting. They had been busy making preparations here for a long time.

The demon hunters fell silent immediately, and the expressions on their faces became more expectant - a mentor-level druid and two top female sorcerers were jointly presiding over the mutation, which added an extra layer of insurance for the success of the experiment.

Then they looked at the small figure lying on the experimental bed.

Leo.

The boy that Lann brought back from White Orchard was supposed to be adopted by the Wolf Clan after his homeland was conquered by Nilfgaard, but now he has been trained by the Griffin School by mistake.

"It hasn't been two years since he was brought back, has it?" Vesemir heard about Leo from the Griffin School. "Has he passed the Trial of Choice? Isn't it too early to let him experience the Grass and Dreams now? At least... five to six years is appropriate, right?"

"That's enough." Kelda motioned to the old wolf to be at ease. "The main purpose of [Choice] is to improve the apprentice's physical fitness to a level that can withstand the trial. He has passed it now. There is no rush to hone combat skills. It would be better to go back and train after he passes [Green Grass]."

"A Trial of Choice that is too long can lead to physical deformities or other abnormalities. This time is the result of our assessment of Leo's physical condition. This is also a new training method we want to try, which is more efficient."

Vesemir was not as good as Kelda in academics, so he nodded.

Everyone looked at Leo nervously.

Lann strode forward and placed his palm on Leo's forehead. He was the last layer of insurance. If there was an accident during the trial, he would use the skill point he had specially reserved to contract Leo, recover from the injury, and interrupt the trial.

"Are you ready, boy?"