The next few days were dedicated to the plague investigation mission.
Triss used portal magic to teleport him, the Witcher, all over Temeria, visiting several villages that had been wiped out by the Catriona plague.
Originally, Guilliman had some expectations due to his bet with Foltest.
He hoped that his arrival would lead to some breakthroughs in the plague investigation.
However, to his regret, apart from hunting dozens of troublesome monsters along the way, he and Triss didn't discover anything special.
They found neither special medicine that could cure the plague nor the Plague Maiden that the sorceress Keira needed.
Apart from collecting samples from the plague-ridden corpses at different stages of the disease, it could be said that they gained nothing.
Hmm? It couldn't be said that they gained absolutely nothing.
At least, after several days of close proximity, his relationship with Triss became closer, turning into friends who could chat freely.
From Triss, he heard many little-known rumors and intelligence that he hadn't heard in the game.
Kingdom politics, noble scandals, and the current situation between the Northern Kingdoms and the Nilfgaardian Empire.
Among them, there were also many stories about the love between Yennefer and Geralt.
Thanks to the widespread dissemination by his good friend and great bard, Dandelion.
The love story between Geralt, the Witcher Master, and Yennefer, the sorceress, was as widely circulated throughout the North as his reputation and those thrilling Witcher tales.
Whether it was for gossip or for stories.
In this era of scarce entertainment, such love stories between extraordinary figures held great appeal for many, gradually becoming an interesting rumor for many people after meals, as they spread through bardic songs.
During this investigation, Guilliman also intentionally or unintentionally revealed his thoughts and understanding of the Catriona plague to Triss.
The most important point was that this plague was actually spread by rats and the fleas on them.
It was necessary to strictly implement measures concerning water sources, personal hygiene, and pest and rodent control, along with a very strict isolation system, to control the spread of the Catriona plague.
Perhaps the people of this world didn't know.
The origin of the Catriona plague was probably the Black Death of the Earth's Middle Ages in a parallel world.
Ciri, the Lady of Destiny, inadvertently brought a flea carrying the Black Death to this world during one of her time-space travels, thus allowing this terrifying rat plague, named the Catriona plague, to spread in the Witcher world.
And the terror of the Black Death is well understood by anyone familiar with that period of history.
Its mortality rate was almost as high as ninety percent, causing tens of millions of deaths in the Middle Ages, almost wiping out about one-third of Europe's population, and also killing tens of millions in Asia.
Even in the original history, humans had not developed a specific cure for the Black Death.
It was only through the human body's natural immune system, strict hygiene protection, and effective isolation that the Black Death slowly faded from the stage of history.
If the Witcher world didn't have magic, the power of gods, and many mysterious forces that couldn't be measured by common sense, the casualties caused by the Catriona plague would probably have been many times greater... After returning to Vizima City.
Because he had investigated several villages consecutively, taking several days, Guilliman received a total of three hundred orens in remuneration from Triss, bringing his assets back to around three thousand orens.
After deciding to rebuild the Witcher School, Guilliman no longer indulged in extravagance and moved directly into the Hairy Bear Inn in the Temple Quarter, preparing to save a good amount of money for the future construction of the school.
His previous plague investigation journey, plus helping Princess Adda remove part of her curse, had restored his Soul Power to over three hundred points.
Without much hesitation, he directly chose to upgrade the [Soul Projection] skill, raising this soul skill from LV1 to LV2.
The activity range of the soul clone expanded from the original ten meters to twenty meters, and the strength of the clone was also somewhat enhanced.
As expected of the exclusive skill granted by Deep Blue, similar to his powerful storage space, the actual effect of the [Soul Projection] skill was far more powerful than those few simple explanations.
Helping Princess Adda lift her curse earlier was an example.
The true soul clone, apart from not being very strong in combat, was simply a powerful assistant that integrated reconnaissance, trial and error, peeping, soul communication, and various micro-operations at the soul level.
It was conceivable that.
When his Soul Projection skill became powerful enough and the controllable distance was far enough.
He could even sit at home and take an enemy's life from a thousand miles away, or even directly use the soul clone to devour the souls of some weak beings.
Just thinking about it made one feel a chill – it was that powerful.
After only one day of rest at the Hairy Bear Inn, and before he had a chance to sample the taste of the streetwalkers in the slums, Guilliman received a letter from Shani.
After these days, the medical student girl had adapted to life in Vizima City and gained the trust of the Sisters of Melitele Temple, now having time to begin research on the Catriona plague.
She wrote to the Witcher to fulfill the commission he had promised her earlier: to go deep into the Vizima swamps to find the special celandine there for use in research on a plague-curing potion.
Guilliman did not refuse this task; the Vizima swamps were a place he had to visit.
As a mature Witcher, he was accustomed to combining several commissions and solving them at once to save time.
Whether it was the first exploration of Black Gull Island to find traces of the Lady of the Lake, or the fat merchant Leuvaarden's task of clearing the swamp docks, or Shani's herb gathering task, and even the commission from Francesca, the most beautiful elven queen, their destinations were all in the same area.
While other Witchers were worried about not having commissions, he had so many tasks that he couldn't finish them all, which was somewhat troublesome.
Soon, Guilliman returned to the house rented by Shani and the other two, meeting the beautiful medical student Shani, and Caroline and her son Alvin.
Caroline was a very virtuous woman, and her pastries tasted indeed good.
The Witcher ate pastries while recounting to Shani the results of his and Triss's investigation in those plague-ravaged villages, and he took out several plague samples he had collected.
Shani was very interested in matters concerning the plague and listened very carefully.
She was a girl who genuinely loved medicine and was willing to devote her energy to the medical profession.
Even in the dangerous environment of the Battle of Brenna, she did not shirk her responsibilities but treated the wounded soldiers at the frontline aid station until the war ended.
After listening to Guilliman's ideas on how to effectively control the personal hygiene of plague patients, how to eliminate rodent and insect infestations, and how to effectively isolate patients of different severities.
His ideas, based on modern medical theories, earned Shani's admiration and approval, and she took many related notes.
After their conversation ended, Guilliman noticed Alvin, who had been sitting quietly nearby, so smart and sensible that he didn't seem like a child at all, suddenly spoke up:
"Alvin, how about becoming my disciple?"
"I will soon establish a Witcher School, and then you and your mother can live there and work for me."
"I will also teach you swordsmanship and knowledge, making you a powerful person."