After the base was surrounded, they stayed on the top of the wall of Base No. 4, leading a group of psychics who could attack from a distance, killing zombies across the wall.

There are more than two million zombies surrounding Base No. 4, while their Base No. 4 has only tens of thousands of combatants and more than 10,000 psychics. They have no ability to open the base gate and go out to kill the zombies. They can only fight a war of attrition and wait for reinforcements to arrive.

However, due to its own problems, Base No. 5 was unable to send reinforcements, and the number of zombies besieging Base No. 4 increased day by day, causing the people at Base No. 4 to become annoyed.

Fortunately, the wall of their Base No. 4 was strong enough, otherwise it would have been breached long ago.

Base No. 4 is not very big, and the number of survivors is only one million. The advantage of a small base is that the area is not very large, and the walls are not very long.

When Shi Dongqing returned to Base No. 4 from Base No. 5, Wen Yubai had a good "talk" with Shi Dongqing and analyzed for him the severe situation they might face in the next few months.

Shi Dongqing admired his boss very much, so he kept her words deeply in his heart.

After he returned to the base, he had a lot of say in Base No. 4 not only because he was the son of the base commander, but also because his cultivation was the highest in Base No. 4.

Shi Dongqing pondered the information analyzed by his boss. There was a great possibility that Base No. 4 would be besieged by zombies. When the city was blocked by heavy snow and they could not go out to perform missions, he devoted himself to having the gold-type and earth-type ability users cooperate with each other to reinforce the wall.

Shi Dongqing is not only a powerful young base commander, but also provides sufficient material rewards. Even those psychics who do not belong to the military will obey his command.

Although Shi Dongqing is not a gold-type psychic, he has learned a lot of gold-type skills from Sister Wenxue, and he teaches these skills to gold-type psychics.

Although it took a full half month and consumed a lot of supplies, all the walls were finally reinforced half a month ago.

As for the reinforcement of the wall, there were bound to be some complaints from the base army because Shi Dongqing had withdrawn a lot of supplies from the base army.

As a result, when the zombies surrounded the city, the people at Base No. 4 realized how foresighted their young base commander was and that it was worthwhile to reinforce the wall.

The reinforced wall of Base No. 4 was so thick that even if the level 2 zombies were hammering it hard, the wall made of metal frame and cement would not move at all, and there was no possibility of collapse in a short time.

Plus the food in the base, it is enough to sustain them for at least a month, so everyone is fine now.

However, they didn't expect that the zombies besieging their base on the ground could not cause fatal damage for the time being, but a crisis occurred in the sky.

Fortunately, there were watchtowers on the four walls, so the mutant birds were discovered from afar.

Shi Dongqing also imitated Base No. 4 and asked the metal-powered people to build a metal safe house in every residential area. When the alarm sounded, most of the residents hid in the safe house.

Only the psychics on the wall and the base troops guarding the wall did not withdraw. They did not have enough time to withdraw, and they could not withdraw because if they left, there would be no one guarding the base gate and the wall.

Although the mutated birds are scary, their numbers are small. If there is no one to defend and a wave of zombies breaks in, it would be fatal, and it would be the lives of more than one million people in the entire base.

The people all hid themselves, so the mutant birds' target was naturally the people guarding the wall.

Although the mutant birds were powerful, there were only one or two thousand of them, while they had more than 100,000 combatants. A few dozen people could deal with a mutant bird. Although they could not kill the mutant bird in a short time, the mutant bird could not capture the combatants of Base No. 4.

The fighters from Base No. 4 and the mutant birds fought for more than an hour. Both sides suffered some casualties, but there was still no winner.

However, the situation is still somewhat unfavorable for Base No. 4, because the superpowers of the psychics have been consumed by more than half, and the fighters who fight by physical strength are also beginning to show signs of fatigue. If they continue, there will probably be a lot of casualties.

At this moment, the people in Base No. 4 who were fighting with the mutant birds suddenly found that the mutant birds flying over their heads suddenly spread their wings and flew high. At the same time, they heard a very familiar sound, which was the sound of the propeller of a helicopter flying.

"There's a helicopter flying towards this side." someone shouted in surprise.

Shi Dongqing hit a mutant bird that was about to fly away with a ball of fire. However, because its supernatural powers had been consumed too much and its energy agents had been used too much, its supernatural powers recovered too slowly. The ball of fire did not cause any damage to the mutant bird. After the mutant bird flapped its wings a few times, the fire on its feathers went out.

He looked up wearily in the direction where the sound of the helicopter came from, but he only saw a dense swarm of mutant birds.

"Could it be someone from Base No. 5?" someone speculated.

At this time, a helicopter flew towards their Base No. 4. Needless to say, it was definitely reinforcements.

Although the sky above their Base No. 4 was filled with mutant birds, no one was stupid enough to suspect that the people on the helicopter were idiots who could not see the situation clearly and drove the helicopter here to die at this time.

There is only one conclusion: the person on the helicopter is definitely a powerful psychic.

"But judging from the sound, it's just a helicopter. No matter how powerful it is, it can't play a big role. At least it can't solve the problem of the zombie siege." Someone said disappointedly.

A helicopter can only carry dozens of reinforcements at most. Given the current situation of Base No. 4, it is just a drop in the bucket and will not play a big role.

Shi Dongqing was originally just looking at the sky tiredly and lifelessly, but suddenly he perked up and stared closely at the end of the mutant bird flock.

He was not the only one with sharp eyes. Soon, those psychics with higher cultivation also noticed it. Other psychics who were slow to realize that something was wrong with their companions also started to stare at that place.

Suddenly, a gap appeared in the dense flock of mutant birds in the sky. At first, the psychics who didn't see the situation clearly thought that it was the gap that the mutant birds flew out of.

But when they found a black military helicopter in the gap, they knew that things were not what they imagined. After they saw it clearly, they knew why there was such a big gap in the mutant bird flock, because all the mutant birds that were within 500 to 600 meters of the helicopter disappeared.

They were really missing. Those mutant birds disappeared without a trace, not even a feather was left.

The mutant birds have a characteristic, which is that they are easily attracted to airplanes flying in the sky and making noises, a bit like moths to a flame.

Therefore, as soon as the helicopter appeared, the "da da da" spiral sound deeply attracted the mutant birds that were hunting humans at Base No. 4. The mutant birds immediately abandoned those psychics and flew towards the helicopter.

But the intelligence of the mutant birds is much higher than that of the moths. At the beginning, these mutant birds did not think anything of it. But when they found that the number of their mutant bird group was decreasing rapidly, these mutant birds felt the danger and immediately flapped their wings and fled.

Thank you to my book friends Bing and Mimi’s Ruby for the tips.

Thank you to Lang Shiliu, Piao Miao & Lu Guang, Xia Fei Man Tian and Mimi’s Ruby for your monthly ticket support.