Tristan waited for Diji and the others to return. He was sitting on the edge of an old house's roof near the alley he was in earlier, his feet swinging back and forth as he cleaned the bloodstains off a bronze coin with a cloth.
The light was fading as night approached, which in most places in that world signaled bedtime. The street activity was no longer as intense as in the afternoon, which was convenient for him.
He turned his head to the side when he noticed someone approaching. It was Diji and his two companions. Again, they were not alone, but this time it wasn't an old, bearded beggar accompanying them. Tristan observed five other youths entering the alley, some of whom looked slightly younger than him, while others were older.
All of them were dirty and wearing filthy clothes. 'Looks like they obeyed me this time,' he thought. Judging by their appearance, he assumed they were all beggars, which indicated that his orders had been followed correctly. For a moment, he thought Diji and the others might kidnap children from nearby homes to save time—not that he'd have had a problem with it.
As Diji and the other children entered the alley, they looked around, searching for Tristan.
"There's no one here! This better not be one of your tricks," one of the older boys said, casting an irritated look at Diji and his companions.
Tristan grabbed a wooden box nearby with one hand and jumped down toward the alley, surprising them with his sudden appearance.
Seeing their worried expressions, Tristan spoke, "As they may have told you, I need your help with something. I will reward you regardless of the outcome."
One of the boys hesitantly asked Tristan, "What do you need us to do?"
"First, I want you to answer a few things," Tristan said, then asked a series of awkward and embarrassing questions about their personal lives and health over the past few days, looking for any signs of serious illness.
Due to his lack of knowledge, he wouldn't be able to detect dangerous viruses or bacteria, so this method was the only option he had at the moment. He considered testing noble children from the city center, who would be much healthier and present a much lower risk of contamination, but given the number of tests he would need to conduct, he decided it wasn't worth drawing that much attention.
They blushed at his questions, and some tried to refuse to answer, but a bronze coin for each of them was enough to get them talking. One boy and two girls were dismissed based on their answers, leaving Tristan with only two left to test.
He performed a visual exam using his diagnostic ability and found nothing too concerning.
"Let's move on to the real test now," Tristan said.
One of the boys gathered his courage and asked, "What do you need us to do?"
"I want your blood," Tristan replied so directly that they seemed petrified.
"What!" they exclaimed in unison.
"Calm down. I only need a drop of blood," he said while thinking, 'For now.'
"You won't die from this."
Tristan took a small sewing needle and pricked the fingers of the youths, letting a drop from each fall onto a piece of glass.
Then he reached inside his clothes and took out two small cups used for drinking alcohol, which he had acquired from the sect's kitchen. A bit of crimson liquid was in the cups—Yue's and Jaeng's blood. Occasionally, Tristan transferred a little Light essence to preserve their blood.
With the sterilized needle, he took a drop of Yue's blood and mixed it with the others. Then he used his Tyrannical Eye ability to examine the reactions at a microscopic level.
Blood type could be analyzed through a DNA test or by observing the reaction to the addition of an antigen. Analyzing DNA was entirely out of Tristan's reach, so he had only one option.
In a normal blood-typing test, blood would be separated using a centrifuge and an antigen, i.e., a reagent, would be added to the red blood cells to see if they react with antibodies, indicating the presence of a specific blood type. With magic, Tristan could simplify the process by directly observing the reactions with his diagnostic spell.
After analyzing the reaction with Yue's blood, he repeated the process with Jaeng's blood.
'Neither of them is compatible.' He was disappointed, though not surprised.
He ordered Diji and his friends to find more people.
---
Test after test, Tristan ended up analyzing twenty-three youths throughout the night until he found four who were compatible with Yue's and Jaeng's blood.
'Apparently, neither of them had a rare blood type. Good to have a bit of luck once in a while.'
He wanted to fill four jars with blood. He considered killing those young people to get all their blood at once but decided it was unnecessary to go to that extreme with innocent people in this situation.
Therefore, he chose to wait until he found four compatible people.
"Well, now only the final step remains." Tristan took four medium-sized jars from his bag. "I need to fill these containers with your blood."
The youths before him turned pale at his words and took a step back. "Isn't that dangerous?" one asked in fear.
He shook his head. "Not at all. You have almost ten jars' worth of blood in your body. One or two won't make a difference. You can trust me. I swear on my honor as a martial artist." Tristan lied shamelessly—he had no idea how much blood he could safely take from people so young.
"Why do you need so much blood?" another youth dared to ask.
"This? Nothing serious; I'm just performing a forbidden ritual." Their expressions of horror at this made Tristan smile inwardly. "Summoning Baloph, sacrificing this blood to him, and breaking my limiter so I can advance my cultivation and ascend to the heavens." Judging by their horrified looks, his words were quite convincing, although anyone knowledgeable would think he was either stupid or suicidal.
He said something so absurd as a diversion in case his actions reached problematic ears.
"I'll also give each of you four bronze ships if you help me."
The youths hesitated, the fear of the unknown filling their minds. However, seeing the coins made it difficult to ignore the call of necessity. They looked at each other as if waiting for someone else to decide first.
"Won't we anger the Spirits by helping you?" A girl murmured.
"You angered the Celestial Spirits before you were even born. Otherwise, you wouldn't be living this kind of life. If you're so worried about the Spirits' opinion, donate the money to a temple and ask forgiveness for whatever you did in your past lives." Tristan repeated phrases he had learned from local religions in recent months. Knowing the afterlife better than anyone, he didn't believe any of it.
Tristan shook a sack of coins in front of them. "You're free to decide. If you'd rather spend this week hungry, I can look for others."
Finally, his words convinced them.
With their permission, Tristan began the procedure.
After leaving the craftsman's shop, he went to Jade Park and sterilized all the utensils with boiling water and fire.
He took several sewing needles he'd obtained from the sect; each had a hole in them created with dark magic.
After filling all the jars with the extracted blood, the youths seemed relatively well. They were a bit slower, but he was satisfied that no one fainted in the process.
As promised, he gave each of them four more bronze coins, enough to buy bread daily for about three weeks.
He gave a few extra coins to Diji and his group—all that spending made his heart ache.
However, when he thought about what might happen if he didn't do this, he felt he'd feel a bit worse letting someone like Yue die this way. As for Jaeng, he could collect on that later.
Now that he had everything he needed, he was finally ready to return to the Flying Sword Sect. In the middle of the night, he ran back to the mountain at full speed.