Our standard issue wooden-handled grenade was comprised of three sections: a cylindrical top encased in sheet metal, affixed to a wooden grip below. Upon detonation, the internal explosives scattered the metal fragments to maim the enemy, though its destructive power was not exceptionally strong.

The big fellow left one grenade behind; I took another. Seeing several fireballs already rushing toward us, I pulled the fuse and tossed the grenade, which hissed and smoked white from its wooden handle.

The grenade exploded in a puff of white smoke. The leading dozen blue fireballs were struck by shrapnel and fell to the ground, extinguished, but more fireballs continued to swarm in from behind.

Luoning took the lead, the other three covering the rear, retreating and firing their semi-automatic rifles. Each man had only about twenty rounds, and within two minutes, they were completely empty.

To deal with those bizarre blue fireballs formed by the strange ladybugs, shooting was the only option; even slight contact would ignite one instantly. A rifle without ammunition was less useful than a fire poker.

The big fellow dropped his rifle, pulled out his last grenade, and shouted to me, "Old Hu, it’s time. Are we doing it or not?"

Luoning and I supported Ga Wa, the four of us forming a circle with the grenade in the big fellow's hand placed in the center. I stared at the grenade before me; the moment the big fellow pulled the pin, in a few seconds, we would all perish together. The final moment had arrived.

In a time like this, I didn't prepare to dwell on other matters. First, those fireballs were getting closer, leaving no time for deep thought. Second, I worried that thinking too much about parting ways with loved ones would weaken me. I always wanted to be a supreme combat hero like Yang Gensi, but to die not on the battlefield, but pointlessly beneath the Kunlun Mountains, was deeply unacceptable. Gritting my teeth, I resolved to let the big fellow detonate the grenade.

Luoning, who had already tightly shut her eyes awaiting death, suddenly thought of something, stood up abruptly, and pulled us back: "Listen to the sound of the water—it’s so loud! We must be close to the underground river. Let’s jump in quickly!"

Just now, preoccupied with firing and then preparing for a suicidal grenade blast, we had completely forgotten about the underground river. In the chaos, we hadn't heard the rumbling of the current. Hearing Luoning now, we remembered there was a way out. If we could jump into the river water ahead of time, those fireballs, however fierce, couldn't harm us.

Easier said than done. Thousands of blue fireballs were just yards away. The four survivors, desperate to live, rushed frantically toward the roaring water.

Judging by the sound, the water was only about ten meters away. We couldn't run far. Rounding the corner at the end of the underground cavern, a massive waterfall appeared before us, plunging into a natural underground lake of considerable size.

Before I could get a clear look, my back felt hot, an agonizing, searing pain. The fireballs must have struck my back. Just a tiny spark would have instantly engulfed me in flame. At this life-or-death moment, there was no time for deliberation; I leaped into the lake.

In the ensuing chaos, I saw the big fellow and the other two also catch fire, shouting as they jumped into the lake one after another. I dove deep underwater, and the blue flames consuming me were immediately extinguished by the lake.

Water and fire repel each other. The remaining insects seemed aware of the lake's power, hovering only two or three meters above the surface, daring not to dive down and attack.

I surfaced to gasp for air and saw the big fellow bob up too, but Luoning and Ga Wa were nowhere in sight. Fearing they couldn't swim and were drowning, I took a deep breath, ready to dive again to save them, when Luoning emerged, supporting Ga Wa.

It turned out Ga Wa had never learned to swim in his life; he choked and passed out as soon as he hit the lake. Luoning saw it just in time, dove in, and brought him up. Fortunately, he hadn't been submerged long. Ga Wa coughed up some water and gradually regained consciousness.

Tibetan custom forbids bathing or swimming in lakes. Ga Wa muttered prayers, begging the Buddha for forgiveness.

The cavern ceiling above the lake was illuminated as bright as day by the glow of countless fireballs. The four of us huddled together. Although it was early spring, the underground water didn't feel cold; instead, there was a slight warmth, suggesting it was a thermal lake formed by geothermal activity.

The big fellow cursed, "Damn it, the guns are gone, sunk to the bottom of the lake."

I reminded him, "We're out of bullets anyway; guns are useless now. Let’s figure out a way to leave. Keep your head low, watch out for those bugs swooping down."

The big fellow, convinced those fiery insects wouldn't dare enter the water, grinned foolishly. His smile quickly froze. Thousands of glowing blue fireballs were gradually converging, forming one enormous mass of flame that rushed down with a whoosh. He quickly submerged himself back into the water.

I inhaled, about to follow, but saw Ga Wa frozen in terror beside me. Being naturally afraid of deep water, he dared not dive under to escape. I had no choice but to forcefully push his head underwater, dragging him by the arm toward the deeper parts.

The giant fireball was tens of meters in diameter. Upon touching the lake surface, it caused vapor to rise in clouds. Though the fireball was massive, the lake was vaster. The suicidal attack of the ladybug suicide squad failed, and they drowned in the water.

The lake bottom was originally pitch black, but the light from above allowed us to dimly see about ten meters down. In the deeper sections, countless large fish were swimming slowly. These fish were completely unlike any I had seen before. The large ones had extremely long barbels, resembling giant salmon. Having lived in darkness, their eyes had degenerated into mere white dots.

I was startled by the strange appearance of these large fish. After swallowing a few mouthfuls of water, I saw Ga Wa kicking his limbs, unable to hold his breath any longer, struggling to swim up for air. Just then, the lake bottom suddenly darkened. I guessed the bugs were mostly dead by then, so I pulled Ga Wa up to the surface.

The lake surface was covered with a layer of dead ladybugs. Without the firelight, everything was pitch black. I shouted to the big fellow, "Big fellow, do you have a flashlight left?"

The big fellow replied, "Lost everything. Nothing left. We’ll have to feel our way in the dark now."

Suddenly, a light flashed before my eyes. Luoning had also surfaced. Wiping the water from her face, she held a military hooked flashlight in her other hand: "This is one of the last two I carried. Luckily, they were in my pocket and didn't fall to the bottom."

The others pulled each other out onto the shore. We were all exhausted and starving, too drained to move. Having gone without food for over ten hours, even if we weren't flesh and blood, even if we were made of iron, we probably wouldn't last.

The big fellow jumped back into the lake and speared a fish with his bayonet. He roughly scraped off the scales, sliced it into several pieces. I tasted first: the raw fish was okay, not very fishy, just slightly bitter. After a few more chews, it tasted quite good.

Only Ga Wa refused to eat it, no matter what. Military discipline also prohibited eating fish in Tibet. But I reasoned that the Kunlun Mountains straddled the border of Qinghai and Tibet. Geographically, we were still on the Qinghai side, and Qinghai had more Hui people than Tibetans, so eating fish here wouldn't break discipline. Besides, discipline mattered little now; we were so hungry our eyes were turning blue. Extreme situations called for extreme measures.

The three of us ravenously ate the large fish raw, feeling unsatisfied. The big fellow swam back into the lake to catch more. Luoning checked Ga Wa’s leg wound, while I walked around the lakeshore, looking for any possible exit. The waterfall current was so strong; this lake must have an overflow point.

The waterfall dropped several tens of meters. Luoning estimated that the waterway before us was likely an underground tributary of the Yarlung Tsangpo River, and there might be underground volcanoes, which explained the warm water.

Taking Luoning’s hooked flashlight, I found a gap in the underground lake where the water flowed out. This waterway was a tunnel about seven or eight meters high, completely submerged, offering no path forward except swimming through the water.

I returned to Luoning and told her what I found. Luoning had lost her map and compass, so she could only rely on intuition. Her years of surveying experience led her to estimate we weren't far from the Unfrozen Spring—a place that never freezes even in deep winter, indicating underground lava. The problem was finding a way back to the surface; wandering underground endlessly was no solution. The only viable plan now was to follow the river, as only where there was a riverbed would we avoid a dead end.

The big fellow returned, dejected; he hadn't caught any fish this time. We didn't want to linger. The three of us who could swim supported Ga Wa in the middle and drifted with the current toward the far end of the tunnel.

Although the surface of this underground river wasn't wide, the undercurrent was extremely strong. Riding the current’s force, we semi-floated, semi-swam without much effort. However, the tunnel was incredibly long, and the water temperature was much warmer than before. The air smelled strongly of sulfur, yet while submerged, we still felt parched.

The big fellow grew somewhat restless, complaining as he swam, "We might have made a mistake with this Leftist adventurism. How long have we been swimming and still no end? The current is so fast here, there's nowhere to stand and rest. We should turn back."

I chastised the big fellow, "What were you doing earlier? Asking how long the Red Flag can fly only after swimming this far out? Are you doubting whether our revolution can achieve final victory? Have you started wavering after taking just the first step of the Long March? Bite down and hold on!"

The big fellow argued weakly, "How can you say that? I was trying to preserve strength for the revolution. If you mess things up like this, who takes the blame for the losses to the revolution?"

Before we finished speaking, Luoning gasped, "Look behind us—is that an animal? It looks like... a water monster."

I also heard an unusual churning sound in the water behind us. I turned back and shone the flashlight. Water was splashing violently, and a huge dark shadow was rapidly approaching from beneath. The flashlight's beam wasn't strong enough to see clearly what it was, but an unwelcome arrival is never a good sign. We all drew our bayonets and prepared ourselves mentally for battle.