204: A mother truly understands her son.

Luo Sen nodded. "Mm. For both professional and maternal reasons, Mom has enjoyed studying my body since I was a child, but it's always been for the benefit of my growth."

The two of them chatted affectionately for half an hour, but Si Nan didn't show any reaction. "There's no reaction at all. On the contrary, when it was first injected, it felt like a clear spring was being pumped into my body, a cool sensation, but after that, there was nothing."

"I'm fine now. Go on and get busy; I'll take a nap and then get up to do some laundry."

Si Nan shooed Luo Sen away. She knew he was waiting to meet up with Gu Jie and the others to start building the Sky Curtain together.

"Go sleep inside; the sofa isn't wide enough." Luo Sen picked her up, placed her on the large bed in the bedroom, and tucked her in.

As she slept, Si Nan was unaware that she was like the moon in the dark night, enveloped by a soft glow. On the surface, there was no movement, but her body was undergoing earth-shattering changes.

Meng Liqi had developed the latest Immune Serum based on genetic modification, taking the essence and discarding the dregs, much like how immortals would cleanse their marrow and refine their bones to improve their cultivation aptitude before training.

It was just that modern medical technology used gene improvement to enhance immunity, using genetic modification to repair physical defects, strengthening and elevating the body's optimal aspects, and transforming a person's body to its most perfect state in a short period.

The Authorities had secretly begun this medical research three years ago. At that time, it was only to improve the physical fitness of active military personnel, but after the zombie outbreak occurred, the research direction was immediately shifted.

Luo Sen was actually the first beneficiary of this welfare, a successful recipient of genetic modification.

Currently, Uncle Ji and the others had also been injected with this serum before executing hunts for large Zombie Beasts, but due to individual physical differences, the effects weren't as significant as Luo Sen's.

At this moment, Luo Sen quietly watched the changes in Si Nan. Already beautiful, her skin became even more porcelain-white and firm, her face glowing like peach blossoms; he was almost unable to restrain himself again.

He helplessly withdrew his gaze from Si Nan's pink lips and curled his lips into a smile. From now on, Nan Nan's physical quality would reach a new level, making her the second strongest in terms of physical intensity, right after him.

Like just now, when they—ahem—she wouldn't feel so exhausted anymore.

His mother really knew him best, knowing exactly what her son was thinking.

Only after Si Nan's body had completely settled down did Luo Sen leave to find Gu Jie and the others to accelerate the production of the Sky Curtain to protect the land. On the way, he informed his mother about the changes in Si Nan's body.

However, after five days of continuous work, even after the Sky Curtain for the Residential Area had been completely fabricated and installed, Luo Sen had not received a reply from his mother, making him feel extremely worried.

In the past, his mother would reply within two or three days at most. Now that five days had passed without any word, he wondered, "Could something have happened even to the powerful Barrier City?"

This thought made Luo Sen break into a cold sweat. He immediately took out his phone to check various important announcements from The Authorities and all the latest news regarding Barrier City. Strangely, there was no bad news about anything happening to Barrier City, which eased his worry slightly.

Just as his heart was still in his throat, his mother finally replied. "Son, Mom knows. Based on what you've said, the Immune Serum has taken effect, so I'm relieved."

"But don't be careless. Nowadays, zombies are evolving every day. Cross-biting leads to cross-infection, and no one can guarantee what they will evolve into."

"Not being bitten is the safest. Your parents have already gone through enough with what happened to you once; we don't want the same thing to happen to Xiao Nan. Do your best to protect her."

"I will, Mom. You need to protect yourself too. Dad surely isn't by your side often, and your research work is the most dangerous. You must be careful."

"You brat, you're worrying about me now? Alright, you're dismissed; your old lady needs to catch up on some sleep."

"Rest well."

The chat ended. This time, Luo Sen felt his mother's mood wasn't as relaxed as before. He didn't ask anything; asking would be useless as his mother wouldn't tell him about any danger.

Therefore, Luo Sen sent his questions to Ji Yan.

The next evening, he finally received Ji Yan's reply: "It was a close call. We brought back part of the corpse of a killed mutant tiger Zombie Beast for research. Unexpectedly, this tiger had evolved a mutation with an immortality function. While the researchers were dissecting its corpse, it suddenly came back to life."

"It killed most of the researchers in the lab and nearly destroyed the entire laboratory. Finally, we used high-concentration sulfuric acid to kill it."

"Professor Meng was also in the lab at the time, but she was rescued immediately and only suffered some superficial injuries, so don't worry. This was our oversight; next time, we will specially treat the corpses of Zombie Beasts before bringing them back to The Base."

"I see. I understand. This can't be blamed on you; the Zombie Beasts are evolving too quickly. Tell me as soon as there's any new information, and I'll do the same on my end."

"Okay."

Luo Sen was finally at ease. He quickly opened the surveillance cameras to check the perimeter of the Residential Area. The Zombie Beasts mixed among the zombies hadn't changed in appearance, possibly because they only moved around the vicinity, and they currently couldn't leap over the heightened walls of the Residential Area.

There were, however, several cat and dog Zombie Beasts wandering around the outer walls, occasionally trying to jump onto the wall, only to hit the smooth surface halfway up and fall back down.

There were also two cats as large as tigers climbing to the treetops, trying to use the springiness of the branches to leap into the Residential Area. Unfortunately, their bodies were too large and heavy; branches as thick as a bowl couldn't support their weight.

In the end, the branches of the entire tree were snapped one by one with a 'crack-crack' as they stepped on them, and the clumsy beasts fell from the branches to the ground time and again.

Then they would get back up, climb the tree, and try to jump from a different branch until all the branches were snapped. Finally, only the trunk remained, but the trunk stretched straight toward the sky without any bend. In their frustration, they hugged the trunk and tried to leap directly toward the Residential Area's wall.

Si Nan arrived and looked in the direction Luo Sen was watching, pointing at the cat leaping mid-air. "Luo Sen, do you think it will succeed?"

Luo Sen withdrew his gaze, hugged her from behind, rested his head on her shoulder, and looked at the zombie big cat. "Of course it won't. The closest these trees get to the wall is over a hundred meters; it would have to be able to fly."

"Besides, even if it could jump onto the wall, the traps up there are hair-trigger and can kill it instantly. And if it's even luckier and manages to jump into the Residential Area, don't we still have a Patrol Hunting Team equipped with fierce firepower?"

"Mm, but the Zombie Beasts that can be resurrected, as mentioned by Uncle Ji, have already appeared. This is too terrifying. Killing one with great effort only to have it not stay dead means all our work was for nothing."

Thinking of this, Si Nan's mood grew heavy.

Then she heard Luo Sen say, "That's why Ji Yan knows he messed up. He definitely didn't destroy that mutant tiger's head immediately. No matter how powerful a zombie or Zombie Beast is, it can't be resurrected without a head."

"That's true." Realization dawned on her, and Si Nan immediately looked at Luo Sen.

But Luo Sen's next sentence made Si Nan give him a punch—