"So cheap," Chen Mang couldn’t help but remark. 4,400 units of iron ore was only enough to feed his slaves for three days. While it felt expensive when he was dishing out food, once he reached the high-level resource deposits deep underground, this batch of slaves would unleash incredible productivity.

At that time, he would have more iron ore than he knew what to do with.

Among all the trains in the "Ironridge Wasteland," he was likely the only one with a "Drill" accessory. That meant the high-level resource mines deep underground were his for the taking, with no one to compete with him.

Unless another train could also brave the "Kunlun Mountains," find a Pangolin and get the drill blueprint.

Once he had mined out all the deep-earth resources in the Ironridge Wasteland, his train, even when it went to a high-level region, wouldn’t be as battered as it was now.

The "Drill" accessory’s level primarily affected two things.

One is the drill’s hardness.

Two, the drill’s rotation speed.

The first ensured that as long as the drill’s level was high enough, almost no rock underground could block the train’s path. A lower-level drill would have to find a way around harder rock formations.

The second determined the efficiency of the drilling.

In other words, it determined the train’s speed while traveling underground.

The speed underground was slower than on the surface. The higher the drill’s level, the faster its rotation, and the faster the train could move underground.

"Let’s go!"

Chen Mang didn’t linger. He summoned all the slaves back to the train and piloted it toward the coordinates of the Apocalypse Abyss.

Several hours later, the Stellar successfully arrived at the Apocalypse Abyss. It switched back to the "Spider Legs" and descended the cliff face. Just as it was about to reach the bottom, the drill extended and began to spin at high speed.

The entire train plunged into the ground like a hot knife through butter, disappearing.

The underground was completely dark.

There was no light whatsoever.

He could only rely on the "Resource Detection Radar," slowly making his way toward the two Level 2 iron mines next to the underground river, two thousand meters below the Apocalypse Abyss. He glanced at the train’s data on the control console panel.

Current speed: 170 km/h.

Not bad, quite fast.

The train’s "Drill" carved out a tunnel for the train to pass through. The displaced earth was pressed to the sides, and as the train passed, the earth slowly settled back into place behind it. It was a temporary underground tunnel, not for long-term use.

It was worth noting—

This time, they wouldn’t have to mine in the dark. Although he still hadn’t acquired a "Headlight" accessory, he had scavenged a lot of supplies during his search for survivors in Taiping City.

There were canned goods, cigarettes, liquor, and more.

Among them were some entertainment items, like paper books and some movie videotapes, as well as some industrial flashlights that ran on batteries. There weren’t many, but it was enough for now.

Soon, Chen Mang, sitting in the control room, could hear the sound of flowing water. The Stellar had finally reached the underground river.

"..."

Chen Mang was the first to jump off the train. He shone his flashlight around, the beam sweeping across every corner. They were now in a giant cavern. The air was quite humid, and in the darkness, the sound of the underground river crashing against the rocks echoed incessantly.

The river wasn’t very wide.

It took up about a quarter of the cavern’s width. The water level was lower than the open area next to it. If there was a sudden downpour, the water level could rise to fill the entire cavern.

The oxygen was sufficient.

At least, he didn’t feel any discomfort breathing alone. He just didn’t know if there would be enough for so many people. They’d mine for now and see. If it wasn’t enough, he’d go on the Train Radio and ask which Train Captain had an oxygen-producing accessory.

He’d buy one.

In the three-quarters of the cavern that was open ground, two pristine Level 2 iron mines sat there, as alluring as the top courtesans in a flower house.

By now, the slaves, under the direction of Lao Zhu and the others, had already lined up to receive their pickaxes and today’s food. They began to file into the mine in batches and started swinging their pickaxes.

Finally—

The pleasant, crisp sound of pickaxes striking ore once again echoed frequently in Chen Mang’s ears.

"Truly the most beautiful sound in the world."

Chen Mang smiled with satisfaction. It was worth the trouble, the near-death experience of braving the Kunlun Mountains. He was very satisfied with the return on his investment.

Next, it was time for him to reap his rewards.

Inside the control car, while the other slaves were busy working, Chen Mang sat alone, his feet propped up on the table. He lit a cigarette and leisurely enjoyed a movie from this world.

He had to admit, it was pretty good.

Quite refreshing.

It was an apocalypse movie. The sense of immersion and engagement was quite strong. If the train wasn’t at the bottom of a cavern but in the middle of a zombie horde, the immersion would be even stronger.

When the slaves were busy, he had nothing to do.

When the slaves were idle, he had to get busy.

That was how the train operated.

The Train Captain decided the general direction, and the people below carried out the specific tasks. Neither could be missing.

Chen Mang looked at the two advanced effects of the "Drill" accessory after it reached Level 10.

[Drill Level 5 Advanced Effect]: Extremely hard, faster rotation speed.

[Drill Level 10 Advanced Effect]: Even harder, even faster rotation speed.

To be honest, this was the first time he’d seen such a pure advanced effect. No mechanics, just simple, pure numerical beauty.

The original effect of upgrading the drill was to increase its hardness and rotation speed.

The two advanced effects were specifically to enhance that effect.

It was conceivable that with a "Drill" accessory of this level, even if other trains also had a "Drill," their speed underground would be far inferior to his.

And...

"..."

Chen Mang was deep in thought. Since this drill was so hard and fast, it probably wasn’t just for traveling underground. He could totally pilot the train and ram it into other trains. He felt that if their armor level wasn’t high enough, it would be difficult to withstand it.

He pushed these thoughts from his mind. He’d been tired for days. For now, he wouldn’t think about these things. Now was his time to relax.

He then turned his attention back to the apocalypse movie on the screen next to him.

In the movie, the protagonist was surrounded by zombies, trapped. Just as Chen Mang was fully invested, wanting to see how the protagonist would get out of this mess, a semi-transparent panel suddenly popped up in front of the protagonist.

On the panel was a line of small text.

"Ding, you have unlocked the ’Get Stronger by Killing Zombies’ system."

"Shit."

Seeing this, Chen Mang was stunned for a moment, then couldn’t help but curse. "Is this how they make movies in this world?"