The teaching building is still some distance from the back mountain, about one kilometer away.

There were many infected people blocking the road on the road, but everyone killed all the way under the leadership of Zhu Jiu, almost unimpeded, and it took almost ten minutes to kill the back mountain.

After Zhu Jiu's strength improved, his perception of the outside world was also much stronger.

He clearly felt that in the past ten minutes alone, the temperature around him had dropped by at least one degree.

It doesn't sound like much at one point, but it's scary to add in the time.

Ten minutes down one degree, an hour is six degrees.

Twenty-four hours a day, if the temperature cools at this rate, the equator becomes the North Pole and the islands become glaciers.

Normally, there are more than 30 degrees in the south of the city this season. According to this calculation, in less than half a day, the entire southern city will be covered with ice and snow and become an ice city.

"Looking at the speed of this temperature drop, my previous guess was still too conservative."

"When this cooling trend does not stop......

Zhu Jiu frowned, according to this trend, can human beings survive the second wave of catastrophe?

With a sword to cut through the infected, he led the group to speed up again.

He was going to collect firewood as soon as possible.

After collecting the firewood, he had to go to the laboratory to bring Ruan Qingyan back.

In this situation, it was too unsafe to leave her alone in the lab.

……

When they came to the back mountain, everyone was shocked.

Zhu Jiu's brows furrowed slightly, and he found that this place had completely changed.

The grass was thick, as tall as a calf, and the grass was hard, like a jungle of thorns.

Moreover, the big trees on the mountain grow much taller than ordinary trees, and it doesn't look like a mountain behind the school, but like a primeval forest, full of century-old trees.

The towering trees seem to have become fine.

In addition, there are many animals shuttling through the dense woods.

These animals look familiar and strange at the same time.

What used to be a palm-sized rabbit has now grown to the size of a kangaroo, at least a meter tall.

Although he was still dressed in white fluff, his scarlet eyes, swollen muscles, and machete-like front teeth made him know that this thing was not simple.

And at this time, this muscular rabbit is biting at a piece of animal corpse on the ground, looking very ferocious.

"The way of the world ......," a student next to him said in shock: "The rabbits have changed to eat meat?" ”

At that moment, there was a rattling sound in the woods.

The sound became more and more intense, and then with a "bang", a huge figure jumped over in an instant.

The muscular rabbit couldn't dodge, and along with the broken corpses on the ground, it was swallowed directly into the belly by this huge figure.

Zhu Jiu fixed his eyes and saw that it was a big python seven or eight meters long.

This python is covered in scales and reflects. Jingguang, like steel armor, knows at a glance that the defense is extremely strong.

Moreover, such a big rabbit swallowed into its belly, its abdomen did not rise and fall, Zhu Jiu suspected that it might not have eaten enough.

Looking at this big guy, Zhu Jiu quietly made a gesture and led everyone around.

Serious matters are important, not troublesome.

The python stared at him for a long time, with human greed and jealousy in his eyes, but finally chose to turn away and burrow into the woods.

After staying away from the python, Zhu Jiu also saw a lot of animals along the way, all of which evolved very terrifyingly.

A centipede half a meter long.

Tank-like wild boar.

A hedgehog that fires javelin-like spikes.

There are also man-eating flowers, man-eating trees, and so on, and there are countless of them.

Zhu Jiu found that both animals and plants evolved in a variety of ways, and there was no law at all.

"These animals and plants have evolved to a much higher degree than humans."

"It looks like they're all good."

"And these guys have evolved like this, and the energy contained in their bodies must have increased a lot."

Thinking of this, Zhu Jiu was a little nervous.

These things are delicious at first glance.

It's delicious and a great tonic.

Zhu Jiu couldn't help but want to get a few tooth sacrifices.

His appetite has increased greatly, especially after practicing the iron cloth shirt, and his daily demand for energy is even more terrifying.

Just eating those biscuits, chocolate, or something didn't do anything at all, just barely satisfied.

And it didn't taste like it was hard to swallow.

It's just that the priority now is to collect fuel, and there is no time to pack up those things.

Therefore, Zhu Jiu pressed the impulse and led everyone to find a secluded place to collect firewood.

At this time, except for Zhu Jiu, who had Zhao Feng's Xuantie Sword in his hand, the rest of the people had no weapons.

Even the two heavy knives before Zhu Jiu were cut off and scrapped by Zhao Feng.

Zhu Jiu thought about it, then turned around and said, "In this way, I will cut down the tree, and you will be responsible for collecting firewood and carrying it back one by one." ”

As he spoke, Zhu Jiu raised his sword and fell, and a towering tree with a diameter of nearly one meter was cut off in an instant.

When the big tree was still in mid-air, the Xuantie Sword in Zhu Jiu's hand turned into an afterimage!

"Boom!"

A big tree turns into a regular piece of firewood in an instant!

"Don't just pick up this firewood, but also go to the neighborhood to pick up some dry firewood, this kind of fresh firewood is not easy to start a fire, and it has to be left to dry for a while before it can be used."

Zhu Jiu arranged it while chopping firewood.

On the side, a tall student with an angular face instructed several students to work according to his instructions, with a clear division of labor and high efficiency.

Zhu Jiu glanced at him and nodded secretly in his heart.

This student's name is Du Jiushan, the one who greeted Zhang Xinyu before, he was the squad leader of their class before, and now he is the team leader, and he is quite capable.

It's just that he's taking a "farmer" evolution potion.

In fact, Zhu Jiu was also a little curious, why did he take the initiative to take the peasant potion, it stands to reason that if he took the combat type potional with his ability, he should be able to grow up quickly.

I was curious, but Zhu Jiu didn't ask, still chopping firewood.

After cutting down two trees, estimating that the firewood was almost up, Zhu Jiu bundled the firewood with a rope made of curtains, was behind him, and beckoned everyone to go back.

But when he saw the struggling appearance of everyone carrying firewood, he suddenly realized a problem, these students' physique is still too poor, and they can carry dozens of catties of firewood at most at a time.

And Zhu Jiu has at least four or five hundred catties of firewood on his back.

It's almost like carrying a tree.

"It's too inefficient."

Zhu Jiu frowned secretly, how many times did he have to carry such a little firewood at a time before he could use it.

Not to mention the low efficiency, it is also dangerous.

Normally, you can drive a pickup truck or something to pull firewood.

But since the end came, the city's traffic was completely paralyzed, and the streets were full of scrapped cars, and the road could not be walked at all, unless another road was built.

Zhu Jiu simply didn't have this time.

"There's no transportation."

Zhu Jiu sighed secretly, but he could only do this first, relying on manpower to slowly carry these firewood back little by little.

"Everybody keep up." Zhu Jiu beckoned to the people behind him, and then took the lead in walking forward.

At that moment, there was a sudden rattling sound in the woods.

Immediately, a big guy burst out of the woods!

……