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The dark dungeon was damp and cold, filled with the stench of decay and human odor, making it a nauseating place to be.

Torches soaked in oil were placed every few meters along the dungeon's moss-covered walls. The torches crackled and sputtered as they burned, releasing black smoke due to incomplete combustion, because of the stagnant air and low oxygen levels, which cast twisted and fearful shadows on the ground.

"Drip, drip," water droplets condensed at the top of the dungeon continually fell, landing on a dungeon guard soldier's head, gradually soaking his hair, then his cheeks, and finally trickling down his neck, icy cold. Yet the standing guard soldier dared not move, his whole body tensed like a Dragon Cavalry's javelin stuck into the ground. He made an effort to keep his breathing steady, but his peripheral vision involuntarily drifted to the dungeon's entrance.

At the entrance, a young boy, fifteen or sixteen years old, dressed in somewhat simple noble attire, walked in expressionlessly. Behind the boy, the Guard Captain accompanied him obsequiously, a fawning smile on his face, but his eyes filled with an uneasy and immense fear.

The Guard Captain couldn't help but feel afraid; the boy was the King's youngest son, the second in line for the throne after the Prince. If the boy was even slightly displeased, he could lose his head at any moment.

Thinking of this, the Guard Captain's heart tightened further; even his facial expression became somewhat stiff.

Richard, however, paid little attention to the Guard Captain's demeanor. He had been in this medieval-like world for fifteen years, and his extraordinary psychological resilience allowed him to fully adapt to his identity here. He realized what actions would most efficiently achieve his goals and unlock his ultimate mystery.

"Da, da, da," Richard stepped forward into the dungeon, speaking to the Guard Captain, "I previously asked you to lead a team to capture a wizard or someone related to supernatural phenomena for my research. You've conducted two attempts already without success, only bringing in a group of ugly farmers as filler. This is your third attempt. Are you sure you've really caught them this time? My patience has its limits."

"Prince, this time… this time…" The Guard Captain instantly broke into a sweat, his Adam's apple bobbing a few times as a stiff voice emerged from his throat, "This time… I swear I've really caught them."

"And what about the situation with the soldiers' benefits?" Richard asked again.

"Huh?" The Guard Captain was taken aback, "Benefits? What benefits?"

Richard raised an eyebrow, "Don't tell me all the compensation for injured soldiers has been embezzled by you alone. If you did that, I'd almost admire your bravery."

"No!" The Guard Captain widened his eyes, realizing and stammering, "Sir… Prince, there were no injuries or casualties."

"Huh? No casualties? Your soldiers captured individuals related to supernatural phenomena without any casualties?"

"Yes, not a single one." The Guard Captain replied earnestly.

"Uh, all right." Richard spoke aloud, having already formed a suspicion in his mind, he continued, "Tell me, what did you catch this time?"

"Yes, Prince." The Guard Captain steadied himself and answered seriously, "This time we captured four: one White-faced Demon, one Half-human, one Vampire, and one…"

…

"Da, da... da!"

After a while, Richard stopped in front of a cell deep in the dungeon, squinting at a figure inside. The individual's skin was unnaturally pale, devoid of any blood color, looking extraordinarily terrifying. He sat on the cell's floor, his eyes filled with fearful apprehension gazing back.

The Guard Captain's voice sounded, afraid Richard hadn't noticed, he said, "Prince, this is the White-faced Demon we captured, look…"

Richard only glanced briefly before proceeding to move ahead.

The Guard Captain was stunned, unsure why Richard was uninterested, but he nevertheless bent his neck and followed.

Soon, Richard stopped for the second time. Within a cell beside him, an odd-looking figure huddled in a corner. The individual's face was full of wrinkles, appearing over fifty years old, yet standing barely a meter tall, like a child, which made people feel a sense of eerie discomfort.

The Guard Captain explained, "Prince, this is a Half-human…"

Before he finished speaking, Richard shook his head and strode forward again, then stopped.

In the third cell was a monstrous-looking human, pale-skinned with red blotches all over his face, neck, and the backs of his hands; some areas were even decaying. His mouth slightly open, revealing teeth that seemed unusually long, with a sinister blood-red hue, enough to send shivers down one's spine.

"Sir… Prince." The Guard Captain pointed to the person in the third cell, visibly nervous, he spoke, "This is the Vampire, you have to be careful not to get harmed by him."

"Ha." Richard sounded; his voice was a bit cold.

"Prince, you…"

Richard spoke, "An albino, a dwarf, and a porphyria patient, these are your White-faced Demon, Half-human, and Vampire?"

"Well…"

"Do you even have any knowledge of biology?! Oh right, I forgot. In medieval times, there was essentially no biology knowledge, but that's no excuse! You should have realized upon catching them without any soldiers being injured, right? Yet for the previous two failures, you didn't learn anything?"

"Uh, well…"

"To say nothing of other matters, take the Vampire for instance, did you see him transform into a bat as per legend? Or can he fly?"

The Guard Captain trembled slightly, but the next moment, he forced courage, "Prince, indeed, I didn't see this wicked Vampire transform into a bat or fly, but his skin truly can't be exposed to sunlight, once in sunlight, it decays. Look at him now, it's because he was exposed to sunlight on the way here. When I captured him, he was also drinking blood, and he particularly despised garlic. Prince, if this isn't a Vampire, what is it?"

"However, he merely has porphyria." Richard proclaimed expressionlessly.

"Huh?" The Guard Captain was baffled.

"In other words, he's just a patient. What you observed are symptoms caused by the disease, albeit much like the legendary Vampire... It isn't."

"Why...?" The Guard Captain was riddled with bewilderment.

"Do you really want to hear the reason?" Richard asked.

"Well…"

"Fine, I'll explain it to you," Richard said, proceeding, "Porphyria, also known as Porphyrin disease, is a group of porphyrin metabolism disorder diseases caused by a lack of certain enzymes or reduced enzyme activity in the hemoglobin synthesis pathway. It can be congenital or acquired, and once it appears, considering the current era, well, there's no means to completely cure it, you can only barely survive, becoming this ghostly appearance."

"Huh?" The Guard Captain was still utterly puzzled.

"Put it this way," Richard offered a more detailed explanation, "Our blood consists of many components, one of which is hemoglobin. Normally, the body synthesizes hemoglobin using 'iron elements' and 'porphyrins' with the catalysis of a specific enzyme. However, some individuals lack that specific enzyme, hindering hemoglobin synthesis, resulting in extremely high 'porphyrins' levels in their bodies.

Porphyrins are highly sensitive to light and harmless in darkness, but once exposed to light, activated by ultraviolet rays, they convert into a 'carnivorous' toxin, causing widespread red spots, blisters, or even ulcers on the body. It also affects the mouth, leading to gum sores and exposed roots, making the teeth appear particularly long, gradually turning purplish-brown due to porphyrin accumulation.

Additionally, since they cannot synthesize hemoglobin fully, they can't produce normal blood; porphyria patients suffer from severe anemia and must supplement blood externally to survive. Intravenous transfusion is one viable method, but given this world's technological level, they can't manage it and must therefore opt for the other—drinking—the hemoglobin has incredibly strong life force, resisting digestive liquids, entering the digestive system to be absorbed via small intestine.

They despise garlic for a simple reason: garlic contains allicin with strong antibacterial effects. Due to their unique physical constitution, consuming garlic can induce and intensely aggravate their symptoms. In fact, if you pierce them with silver objects, they'll equally detest it—silver also poses a formidable antibacterial action.

In short, you must understand: Vampires are Vampires, while porphyria is porphyria. Maybe their manifestations appear somewhat similar, but they are not the same at all! What I want you to find are true Vampires and phenomena relating to wizards and spells, not merely find patients, understand?

When you captured them, they didn't resist or kill; they pleaded and wailed—in your heart, you didn't question anything at all? Huh, or do you think merely accomplishing the task on the surface is sufficient? The first two times were like this, and now the third time too. My patience is really limited..."

"Prince, I..." The Guard Captain could no longer speak, his heart overwhelmed with enormous terror. He'd heard many cruel stories about the Prince, and if the Prince was truly angered...

Richard didn't continue entangling with the Guard Captain, proceeding to stride toward the deepest part of the dungeon, speaking, "You said you captured a fourth, a true wizard. Well, let's see if it's genuine or not."

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