The flashlight beam was still stuck at the corner of the guide channel. Chen Hao had just pried the clump of rotten leaves out when the iron pipe vibrated again. This time, he didn't pull his hand away; instead, he pressed his palm even tighter, as if he were touching a hot electrical wire.

“It’s not a water pump,” he muttered. “A water pump vibrates with a long hum, this… it’s pulsating, like a heartbeat.”

Nana's voice came through the earphones: "The vibration frequency is seventy-two times per minute, which is highly consistent with the human resting heart rate, but it originates from non-biological cardiac activity."

“I know it wasn’t someone drumming down there.” He withdrew his hand, stuffed the sampling bottle into his pocket, and said, “Let’s go back inside first. I’m afraid if this thing crawls out again, it might recognize its ancestors.”

The lights in the control room were on, and the ecological data stream on the screen was still scrolling. He shook the mud off his shoes, and without even taking off his raincoat, rushed to the microscope stage, pouring the residue onto the slide. Nana automatically focused, and the image switched to the holographic screen.

A group of translucent insects wriggled in my field of vision, like noodles that had been scalded.

"Nematodes?" Chen Hao squinted. "These days, even insects are starting to do group workouts?"

“To be precise, they are variants of soil nematodes.” Nana’s tone was as flat as reading an instruction manual. “Nano silver deposits were detected in their bodies, and abnormal ganglion discharges caused them to move synchronously in groups. Now, they take one step and shake three times, like they are doing square dancing.”

"Goodness, eating too much silver can even make you go clubbing." He leaned back in his chair, looking up at the ceiling. "Last time the bugs were gnawing on metal, this time the bugs are setting the pace. Is our farm about to become a biological performance art exhibition?"

"There are currently no records of audience ticket purchases," Nana said. "Furthermore, this phenomenon may interfere with the underground sensor network, so we recommend removing it."

"What's there to clean up? They didn't steal any chickens." He waved his hand. "As long as they don't dismantle my frame, let them jump if they want. It saves me money on deworming medicine. I can raise a bunch of them as live vibrators later."

The alarm went off as soon as he finished speaking.

It wasn't a high-pitched whistling sound, but a low, continuous "beep-beep," like someone honking a car horn for help.

"Level 3 alert for poultry area." Nana switched the screen. "Three antibody chickens have body temperatures exceeding 42 degrees Celsius, have lost feathers in some areas, and their blood viral load has risen to 320 million units per milliliter."

Chen Hao sat up abruptly: "Didn't we already get the serum?"

"It becomes ineffective seven hours after injection." Nana pulled up the gene map. "A new variant of h5N3 has emerged, with reorganized RNA shell structure, making it impossible for the original antibody to recognize the binding site."

On the holographic screen, the virus model slowly rotated. The originally smooth shell became uneven, like clay that had been kneaded by a child.

"It's learned to wear a vest?" Chen Hao reached out and poked the projection. "It used to be a cloth outfit, but now it's wearing a bulletproof vest?"

“The analogy is inaccurate,” Nana said. “It’s closer to replacing the lock cylinder and the original key becoming invalid.”

"Do we have someone who can make a key?"

“The base has no relevant synthetic equipment.” She paused for half a second, “but the database shows that this type of RNA virus relies on reverse transcriptase to complete replication. If the activity of this enzyme can be inhibited, proliferation can be blocked.”

"So we need an ink... specifically designed to kill photocopiers?"

"The technical principles are similar."

“Okay, so here’s the question.” He shrugged. “Where’s the ink? Do we have any in stock?”

“No finished products in stock.” Nana pulled up the inventory list. “Artificial synthesis requires specific biological raw materials, which we do not currently have.”

Chen Hao was silent for two seconds, then suddenly burst out laughing: "Isn't this a coincidence? Last month I was thinking that the chickens were too healthy, and I was thinking every day about how to find some diseases to treat them so that I could show that I was useful. It's only been a few days, and they are really sick, but we're out of medicine."

“You never expressed that wish,” Nana corrected, “and the current situation is not suitable for humor.”

“I’ll die if I don’t have a sense of humor.” He rubbed his face. “People tend to talk nonsense when they’re nervous; it’s a physiological instinct. Look at those war correspondents; they can still tell jokes even when shells are hitting them. It’s not that they’re brave; it’s that their brains automatically switch channels to save their lives.”

Nana didn't reply, but the screen had already started scrolling through search results.

"We are comparing antiviral mechanisms of Paleozoic microorganisms... a match has been found. Among the primitive cyanobacteria, some strains secrete substances that can naturally inhibit the reverse transcription of RNA."

The camera switches to an overhead view of the ecological area's pond. A layer of green film floats on the water's surface, with a slight bluish tinge at the edges.

"There is an 83 percent chance that the same strain exists in the sediment layer in this area," she said. "It is recommended to collect samples for activity testing."

Chen Hao stared at the circle of blue light for a few seconds, then suddenly got up, walked to the locker, opened the drawer, and rummaged through it.

"Are you going to collect samples?" Nana asked.

"What else can we do? Wait for it to swim up and write its own application?" He pulled out an old mineral water bottle and took a piece of PVC pipe. "We don't have professional tools, so we can only use makeshift methods. Anyway, we're not allowed to go into the water, so I'll just grab some from the shore. At least I won't be penalized for crossing the line."

“Contamination must be avoided during the collection process,” Nana cautioned, “and there may be other unknown microorganisms in the water.”

"Got it. Wear gloves, don't drink untreated water, and don't date by the pool." He said as he tied a rope to the bottle. "You robots always make simple things sound like you're signing a death warrant."

"I'm just stating the risks."

“I know the risks.” He tightened the knot. “The biggest risk is that I go down there and it turns out that it’s not blue-green algae at all, but moss. Then we’ll have lost a lot of time and effort, not to mention we’ll have to listen to you lecturing on ecological ethics for half an hour.”

Nana did not respond, but the monitor automatically switched to the live feed of the pool, focusing on the fluorescent area.

Chen Hao carried the homemade sampling rod outside and stopped briefly as he passed the control panel.

"Hello."

"exist."

"If I fall into the water later, don't pull me out right away."

"Why?"

"If it happens to crush that patch of blue-green algae, it could be considered a blessing in disguise." He grinned. "You can just say it was a strategic plunge into the river."

The rain hadn't completely stopped outside, and the ground was slippery. He walked towards the pool, his feet sinking into the water, carrying the pole on his shoulder like a farmer preparing to hunt a dragon.

Nana's voice came through the earpiece: "The optimal collection route has been planned, avoiding steep slopes and soft ground. The current humidity is 91%, so please watch your step."

"Received." He stepped forward, stepping on a half-buried stone slab. "Why did you think these strains needed to fight RNA viruses back then? They're not chickens."

“It is speculated to be related to the struggle against ancient bacteriophages,” Nana replied. “Early life forms on Earth faced a large number of RNA virus attacks, and some cyanobacteria evolved defense mechanisms to maintain population stability.”

"Got it." He stopped and squatted by the pool. "Those things that survived all have some skills. Now we're going to borrow a skill and see if our ancestors left any instructions."

The water was calm, and the green film swayed gently in the breeze. He slowly extended the PVC tube with the bottle attached, trying to scrape off the surface layer with the bottle opening.

The first time I misaligned it, the bottle tilted and almost tipped into the water.

"Ouch!"

He frantically pulled it back; the bottle was wet and only half-filled with muddy water.

"Second attempt," he gasped. "This is much harder than playing the claw machine."

Adjusting the angle, I tried again. This time, the bottle opening grazed the edge of the green film, stirring up a small amount of flocculent material.

"Done!" Just as he was about to reel in the line, his fingertip suddenly went numb.

It's not static electricity.

It was a slight but persistent tremor that seemed to seep into your bones.

Looking down, I saw the PVC pipe in my hand was trembling slightly.

It's not the wind.

It wasn't that his hands were shaking.

The entire pipe, along with the rope and the mineral water bottle, was swaying gently in a certain rhythm, as if being moved by an invisible hand.

He froze, too afraid to move.

"Nana".

"exist."

"Did you see the screen on my end?"

"I see. The vibration is traveling from the bottom of the water along the piping system toward your location, and the frequency is the same as that of the nematodes in Zone B."

He slowly raised his head and looked into the depths of the pool.

The green film continued to float, and there was nothing unusual about its surface.

But the moment he looked at it, the circle of blue light suddenly flashed.

It's not a reflection.

It emits light internally.

It looked like something had opened its eyes below.