Lake bottom mine

Seekers who have survived until now basically have their own medicine reserves, so medicines are not as valuable now as they were in the early stages.

If it were in the early stages, how could Lin Feng possibly use medicine to trade for these useless building materials?

"101, can you help me weld these iron plates together?"

Lin Feng remembered that 101 had many tools, so he should have a welding machine, right?

"Yes, Mr. Lin Feng."

As he spoke, 101's mechanical arm transformed into a pen, not a welding machine. Lin Feng didn't know exactly what it was, as long as it could stick the iron plates together in the end.

Half an hour later, Lin Feng obtained a hollow iron cylinder 15 meters high and two meters wide on each side.

He wanted to use the most clumsy method to separate the water.

This height completely exceeded the depth of the lake.

After returning to the lake, Lin Feng directly inserted the huge hollow iron cylinder into the bottom of the lake, then pressed down hard, finally succeeding in embedding the iron cylinder into the soil.

Now, all he had to do was pump out the water inside.

This was very simple; he just needed to use his spatial ring to collect it and then transport it elsewhere.

Another thirty minutes passed, and the suspected cave area was finally dried by Lin Feng.

Although water kept seeping out from the four sides and the soil, it no longer affected anything.

After taking out the Dark Miner's Pick from his spatial ring and digging downwards for more than ten minutes, a dark hole indeed appeared.

"Hahaha, this place really has a hidden wonder!"

Lin Feng was delighted when he saw the cave. He quickly enlarged the entrance and then entered the cave.

Night mode was immediately activated, and the entire scene of the lake bottom cave was clearly displayed before Lin Feng.

"Oh my, this cave is actually so big!"

No, this shouldn't be called a cave; it's more like a mine.

This mine alone had an open area of tens of thousands of square meters, not to mention the small branching paths extending from it.

From the stones on the walls, it was also evident that there were traces of human excavation here.

So, does this permanent floor world have a civilized society?

If Lin Feng wasn't mistaken, the ice crystal stones that Huangdou found should have been produced from this mine.

It's just unknown if there are any remaining ice crystal stones inside this mine.

For the next few hours, Lin Feng explored this mine at the bottom of the lake, but he had no gains.

It was exploited very cleanly here.

It was clearly an abandoned mine.

"Forget it, let's go back to the Elevator. The materials for upgrading the Elevator should be enough."

Lin Feng sighed, preparing to return the way he came.

At this moment on the lake surface, the steel plates that had been fixed to block the lake water began to slowly shift. As a large amount of lake water poured into the gaps created by the shifting, the iron plates also lost their function.

However, this lake water would not cause any impact on Lin Feng. The reason he wanted to isolate the lake water was that he was worried there might be good things in the cave that would be difficult to find once submerged. Now, if it's submerged, then so be it.

Returning to the Elevator.

Lin Feng hammered the damaged transparent mask, and it was indeed repaired. After putting on this suit, Lin Feng looked in the mirror and found that if he stood still, he could still see a slight trace.

For example, the color at the edges would be darker.

Not to mention when running, although it was the same color as the surrounding environment, it could be easily spotted.

This kind of clothing is suitable for use in places with a single color.

Such as deserts, grasslands, jungles.

The concealment in these environments is the most outstanding.

Lin Feng wouldn't be using this suit, after all, he usually wore battle armor, and this stealth upgrade set couldn't be worn over the battle armor, so he would just leave it in the warehouse to gather dust for now.

Arriving in front of the material stacking area, Lin Feng checked the materials he needed to upgrade to level 22.

He found that he was only short of 3 upgrade sets.

Now, he only needed to purchase all the upgrade materials for 3 upgrade sets from the market, and then he would have gathered everything.

However, when Lin Feng opened the Exchange, he was stunned.

The upgrade sets that had always been on sale were all gone!

Actually, thinking about it, it was understandable. Now that the Elevator rules had changed, Seekers could have a permanent floor world after level 20, so they had the motivation to upgrade their Elevators again.

That's why all these relatively rare upgrade materials were delisted.

Ultimately, Lin Feng still managed to acquire three upgrade sets in the chat room at a price of three hundred gold coins each.

After putting the upgrade sets into the material stacking area, Lin Feng was only one upgrade mission away from upgrading.

However, Lin Feng had a feeling that this upgrade mission would be extremely difficult.

..........

Hours later, Lin Feng, who had gotten out of bed, checked the time. It was just right; a new floor was about to arrive.

"Beep, the host is about to enter the City Apocalypse Floor. This floor has a large number of zombies and mutated creatures. Please proceed with caution."

"Beep, warning: No items can be carried into this floor. You can choose whether to enter this floor."

"Beep, mission issued: Please thoroughly kill the Special Mutant. Mission reward: Random skill draw."

"Beep, congratulations to the host for triggering the 'Challenge Master' title. The rules of this floor are ineffective against you."

..........

Listening to the series of system prompts, Lin Feng was a bit confused.

After sorting it out in his mind, Lin Feng suddenly felt that the probability of this 'Challenge Master' title might be controlled by the system, right?

Otherwise, why would it come so coincidentally!

As for that Special Mutant?

Lin Feng now had enough strength to punish him.

However, he still needed to wear his battle armor, after all, the Special Mutant had many attack methods.

And he changed very flexibly, which could be said to be unpredictable.

Most importantly, Lin Feng didn't want to get infected with the virus.

This floor's Elevator did not issue any missions, so the time limit was still five hours.

The Elevator would close after five hours.

"Time is a bit tight... Why didn't the system give me a target locator this time?"

Lin Feng said with a headache.

Manhattan City was not small, and he didn't know if he could find the Special Mutant within five hours. Forget it, if he was lucky, maybe he would run into him right after going out.

Lin Feng thought to himself. Soon, the Elevator's broadcast sounded.

"Ding dong! The Elevator is descending. Please hold on tight."

..........

Leaving the Elevator, Lin Feng immediately operated his battle armor to fly into the air, looking at the city.

Suddenly, a small black dot appeared in the distant orange-red sky.

"Found him!"

Lin Feng chuckled.

Jumping so high, besides the Special Mutant, no other creature should be able to do it, right?

..............................