038 Let Me Teach You

"Don't... don't be so anxious. If it were you trapped there, we would certainly find a way, but it's not you right now."

Zheng Xinyu spoke weakly, not daring to meet Zhang Su's eyes after being reprimanded. Zhong Xiaoshan scratched her head, remaining silent and feeling equally awkward.

"You must use your brain at all times; otherwise, how will you be able to come up with a solution when a critical moment arrives?" Zhang Su sternly lectured the two, then continued, "I hadn't intended to help that guy, but I'm making an exception this time to teach you both. Pay close attention!"

He needed to provide a rational explanation for why he was intervening, as it contradicted the survival philosophy he had been teaching them.

"Oh, oh, we'll pay close attention."

The two spoke in unison, not sensing anything amiss at all.

"Since we already know that zombies are highly sound-sensitive, we can fully exploit this to lure them. The people who left the city earlier, the group of five that escaped the compound, and the neighbor downstairs who used the elevator to transport the zombies—didn't they all use this same principle?"

As he spoke, Zhang Su walked into Zheng Xinyu's room.

"But we don't have a drone, nor do we have a megaphone. Even if our phones have a playback function, are we supposed to hold them outside the window? Not to mention whether the sound would be loud enough, wouldn't we just be luring all the zombies to our building?"

Zheng Xinyu looked on, puzzled, as Zhang Su squatted on the floor, rummaging through express delivery boxes.

Zhang Su didn't stop his hands. He gathered some packing foam together, then pulled a mobile phone from his pocket and said, "A regular smartphone has limited volume, but this kind of old-fashioned feature phone is different..."

With that, Zhang Su powered on the phone he had previously turned off.

*Jingle-jangle...*

A loud, boisterous melody erupted in the room. It took everyone by surprise without warning; even Zhang Su, who had been mentally prepared, felt his mouth twitch.

"You heard that... Even if this sound were played in an open garden, it would be quite explosive. It could attract zombies within a hundred-meter radius at the very least!"

Zhang Su actually felt a bit reluctant to part with the old phone. He only had two in total, and they were incredibly useful, but the thought of the S-rank challenge reward made that reluctance vanish.

"Brother Su, are you planning to bundle the phone with this foam and throw it downstairs to attract the zombies' attention? That way, the person will have a chance to escape, right?"

Zhong Xiaoshan had largely grasped Zhang Su's plan.

Zhang Su did not answer. Instead, he looked at Zheng Xinyu and asked with a smile, "What do you think of Xiaoshan's method?"

Zheng Xinyu thought for a moment and said, "It seems fine, but... this foam isn't very sturdy. With the strength zombies have, can it withstand being torn apart?"

Zhang Su nodded with satisfaction: "Combine the concerns you two have raised, and you've got it!"

He began his work, leaving the speaker end slightly exposed while wrapping the rest in thick layers of packing foam.

Next, he wrapped the exterior with packing tape. This was the crucial step to prevent tearing. The packing tape he had retrieved from unit 1101 was durable and highly adhesive; even with a zombie's strength, it wouldn't be easy to destroy in a short time.

Looking at the yellow ball in his hand, Zhang Su was very satisfied. He pushed the phone deeper inside so the exposed part retracted into the foam ball, creating perfect protection without obstructing the speaker.

He turned on the phone's ringtone—only at a low volume—and threw it from the bed to the floor. The foam-wrapped ball was bouncy, and even as it hit the floor, the phone kept playing its cheerful tune.

"Mission accomplished. Let's go see if our phone, which is tougher than a brick, can stand the test!"

Zhang Su tossed the ball in his hand, quite pleased. He had considered attaching a plastic bag to the outside of the foam ball as a makeshift parachute, but decided against it, fearing it would create too much drag when thrown.

Watching Zhang Su head for the main door, Zhong Xiaoshan pointed to the bay window in confusion and asked, "Brother Su, aren't we throwing it directly from here?"

The person trapped was on the east side of Building 4, while Zhang Su's unit was on the west side of Building 3. Throwing it from there would lure the zombies between Building 3 and Building 4 toward the west, creating space for the person on the east side.

"Remember, even when helping others, you must never compromise your own interests!"

Zhang Su habitually checked the situation outside, touched the keys in his pocket, opened the door, and whispered, "Since we're luring the zombies away anyway, why not lure them to a different building?"

The two women realized his intent and quickly followed Zhang Su.

They climbed the emergency stairs. As they neared the twelfth floor, Zhang Su signaled them to tread lightly. He pressed his ear against the security door and listened; a low, rattling sound emerged from a throat, like someone with a glob of phlegm stuck in their windpipe—it was nauseating.

Zhang Su pointed toward the roof without lingering. He had made up his mind: sooner or later, he would take care of these creatures.

"Brother Su, it's locked!"

Zheng Xinyu pointed to a palm-sized padlock on the door leading to the roof, looking discouraged.

This lock was clearly not one of those flimsy ones meant for show; it looked very sturdy and couldn't be easily forced. In the current environment, they couldn't use weapons to smash it, as the massive noise would inevitably trigger a zombie riot.

"Leave this kind of problem to your brother!"

Zhang Su handed the ball to Zhong Xiaoshan, carefully pulled a key from his pocket, found the right one, inserted it into the keyhole, and gave it a gentle twist.

*Click.*

Zheng Xinyu and Zhong Xiaoshan stared in disbelief.

"This... how do you have the key to this lock?" Zheng Xinyu asked the question that had been weighing on her mind.

"What's so strange about that? I have a good relationship with the security guard. I told him I liked watching the stars and drinking beer on the roof, so he gave me a key. Is that so hard to believe?"

Zhang Su removed the lock and tucked it into his pocket.

In the past, Zhang Su was not only generous with his employees and business partners but also with the people he encountered daily.

For instance, the security guards, cleaning staff, and even the man who collected the trash—he would offer them a cigarette whenever they met. It was precisely because of this that he enjoyed so many conveniences.

"Fine, fine. The black-hearted landlord who extorts my money is so generous to everyone else. Hmph!"

Thinking of this, Zheng Xinyu felt aggrieved. It seemed everyone else could take advantage of Zhang Su, except for her, who always came out on the losing end.

*Thump.*

Zhang Su tapped Zheng Xinyu on the head. "This is teaching time. Who told you to space out?"

He then gently pulled open the heavy door. A beam of blinding sunlight hit their faces, stinging their eyes.

*Whoosh.*

Before the three could step onto the roof, a cold gust of wind blew, making Zhang Su, who was holding the door to observe the situation, shiver.

"It's all clear!"

With that, he signaled for the two women to follow him onto the roof.

The roof's layout was simple. There was a five-foot-tall concrete parapet on all four sides, with several ventilation shafts in the center. Solar water heaters were lined up neatly on one side, and a dustpan and broom sat in the corner. However, the ground was thick with dust, showing that it hadn't been cleaned in a long time.