Train Survival: You're really trying to survive!

Of course, nothing happened.

Even in this life-or-death situation, Su Li was still able to control herself.

After resting with their eyes closed for a while, the two of them slightly raised their body temperature to calm the elemental erosion in their bodies.

Su Li then continued digging the pit. As Black Iron-level superhumans, their physical recovery speed was very fast, and they did not need much sleep each day.

However, digging by hand is extremely slow.

The excavation of the passage continued, and relying on Zuli's perception of the water element in the outside world, they determined the route they would take next.

"The cross-section of this underground river is like a U-shape, and we are stuck at the bottom. To get out, we first need to dig horizontally for about 40 meters in this direction, then dig diagonally upwards for a distance, and finally spiral upwards."

The place where Su Li and the others fell into the water was in a mountain range. After falling into the water, they didn't know how long they had been drifting. Su Li could only try to be as thorough as possible.

Digging upwards in a spiral pattern avoids the unfortunate situation where the sloping passage is at the same angle as the mountain's slope, preventing the digging from reaching the top of the mountain before finally breaking through.

Su Li was actually quite unsure, because the temperature here was much higher than on the ground, and even the elemental erosion was much slower, which meant that they were buried very deep.

Realizing this, Su Li took out the selectable item box and blueprint box that she had been rewarded with after the beast tide, and searched for items that could break the current situation.

First, open the blueprint box and see what you can use.

Su Li glanced at the contents; most of them were equipment blueprints, and she even saw a few blueprints for silver-level equipment, but she rejected them all. These pieces of equipment required higher-level crafting tables, so they would be useless to her.

"The rest is useless. The contents of the box are equivalent to the late-game Black Iron level, and all of them require a crafting table. We can't use them even if we take them."

Su Li closed the blueprint box with a sigh; now, she could only look at the prop box.

Please choose one of the following items as your reward.

【自选金属锭*5】【自选药剂*5】【精致背包*1】【背包增容道具（10格）】【自选元素晶石*5】【寒霜剑*1】【踏冰靴*1】【抑冰药剂*5】【抗冰菌合剂*5】【雪隐斗篷*1】【秘食·寒冬宴】

The rest were various miscellaneous props, many of which were clearly not intended for human use.

The bad thing is that as the selection box level increases, tools like pickaxes become less visible.

Su Li had her eye on two of the props.

One is the Snow Cloak.

【Snow Concealment Cloak (Black Iron Grade)】

[Explore the equipment; wearing it grants resistance to ice elemental erosion, allowing you to maintain stamina and remain invisible in snowy or blizzard conditions.]

This item must be replaced.

Another one is the Secret Recipe: Winter Feast.

[Secret Recipe: Winter Feast is a set meal that can be enjoyed by four people.]

[After use, it removes all ice elemental damage and bacterial infection from the user, and permanently increases the user's ice elemental resistance.]

Whether it's an outbreak of elemental bacteria or damage from elemental erosion, ice elemental resistance is crucial.

Su Li hasn't redeemed it yet; it will only be able to maximize its effect once she has accumulated enough elemental erosion.

The bad news is that he didn't find any oxygen-related items in the item box.

Looking at the empty space, Su Li felt very worried.

I don't know how long this oxygen will last.

Inside the cave, there was no sense of time. The clock in the manual was out of service, so Su Li and the others could only keep working, resting when they were tired, and digging when they were rested.

Su Li didn't know how much time had passed; all he knew was that the air in the cave was becoming increasingly murky. A stifling feeling gradually crept over them.

The original tree hole had been filled with excavated soil, so Su Li and the others could only move their food and other items to their inventory.

To make matters worse, the shovel ran out of durability after only a short time, turning into a glowing spot and disappearing.

This is also a drawback of using the system to create props; once damaged, they turn into light. If you create them yourself, even if they break, you can still keep the broken draft.

Having lost his tools, Zuli had no choice but to recreate the props.

He only had iron on him, and if he wanted to make iron tools, he needed a forging table. Where could he find a forging table here? The 10 iron ingots that Su Li had on him were simply not enough to make one.

Zuli had no choice but to switch to a stone pickaxe. There wasn't much of anything underground except for rocks and dirt.

After switching to a stone pickaxe, the efficiency dropped significantly.

During this time, Su Li brought out a Winter Feast. The two of them hurriedly ate this Winter Feast. With a bright future ahead, even if it was a delicious secret dish, they didn't feel anything after eating it.

Furthermore, Su Li also exchanged a backpack expansion item from the item box for Song Mingyu to use.

"Day after day, my job is to keep digging holes. The more I dig, the bigger the village becomes, and the village chief will happily feed me mole-pigs. Oh no, philosophically speaking, it should be wolf-deer." Su Li dug a hole, making the best of a bad situation by reciting lines from an anime she had watched in her previous life.

"A mole-pig? What's that?" Song Mingyu sat next to Su Li, panting heavily.

They had just changed shifts; the two of them took turns mining, switching places when one got exhausted. The other person used their inventory to transport the excavated soil downwards.

"A line from a certain anime, which I'd call the pinnacle of 21st-century inspiration." Su Li suddenly became animated, digging hard into the ground. "My drill bit is a drill bit that can pierce the heavens!"

"Ha, the drill is piercing the sky, what's it going to do?"

"To drill a wind tunnel through the universe and open up a new future... or something like that."

Song Mingyu scratched his head, picked up a pebble from his hair, and asked, "A new future?"

“Yes, a new future,” Su Li said affirmatively.

"..." Song Mingyu raised her head. The air in the cave was foul, there was no light, and it was icy cold.

No matter how you look at it, this place feels like hell. There's no light, no heat, no future.

As Song Mingyu waited there for a long time, she occasionally heard tinnitus, and she knew that there seemed to be something wrong with her mental state.

Here, silence and the sound of digging are the main sounds. The two of them would occasionally exchange some words, but after getting tired, they had nothing left to say.

Song Mingyu shook her head, feeling her breathing quicken, her heart race, and fine beads of sweat appear on her neck.

She suddenly stood up and hugged Su Li from behind.

Su Li stopped moving abruptly.

He could feel Song Mingyu's heavy breathing behind him, but the sound brought him no pleasure, only panic.

"Sorry, let me hold you for a bit. I'm a little panicked..." [This could be a precursor to claustrophobia.]

Song Mingyu didn't say the last sentence, because saying it would only increase Su Li's pressure.

"It's alright, I'm here." Su Li held Song Mingyu's hand and gently touched the blisters on Song Mingyu's hand with her fingertips.

"Su Li, do you think we're doomed to not escape?" Song Mingyu's voice was somewhat muffled.

“Impossible. I won’t let that happen,” Su Li replied firmly.

"..." After a long while, Su Li felt the hands that were holding her loosen.

"I'm sorry, I'm such a grown-up, yet you're the one who has to comfort me."

"I'm actually quite happy to have seen another side of Mingyu."

“…Mingyu, just call me Mingyu.”