The Hellhound walks around from time to time, and the ten second-level mutated creatures around it are its sentinels, and whenever it moves, the sentinels move with it.

The Hellhound is moving, but its sight is always on the bell tower.

Obviously, the Helldog Two-Headed Dog wanted to be more patient with Su Chen, and it firmly believed that Su Chen would take the initiative to find it, instead of spending a lot of effort to destroy the first-level zombies with no end in sight.

The Helltwo-Headed Dog was right, even if Su Chen had the ability to destroy these zombies, after he finished destroying this group of zombies, Dragon City's combat materials would be exhausted, this was a loss and not a profitable deal, and Su Chen could only give priority to attacking the Helltwo-Headed Dog.

In fact, Su Chen has another way, that is, to find a second-level defensive zombie, kill it, and then accumulate experience to reach the fourth-level immunity.

Once he becomes a level 4 immune person, his overall strength will be far stronger than that of the Hell Two-Headed Dog, and the battle will not need to start at all before he can already announce the result.

The ideal is very plump, and the reality is very skinny.

Su Chen was able to determine that the zombie groups inside and outside the Dragon City had reached 10,000!

With so many mutated creatures and zombies, it stands to reason that even if there is only one in ten thousand, defensive zombies should appear at this time.

But Su Chen's Baibao didn't find it...

Judging from the zombie illustrated, defensive zombies are not rare, but second-level defensive zombies are a very rare species, and first-level zombies do not have such a category as defensive ones.

Regarding the fact that second-level defensive zombies are more rare than third-level defensive zombies, the Zombie Illustrated Book has a clear explanation.

After the zombie mutation reaches level 3, there will be a chance to "change jobs", such as speed zombies can be transformed into defensive zombies!

Because there is no such thing as a defensive zombie in the first-level zombies, the second-level defensive zombies are all evolved from the second-level ordinary zombies, so the number will be scarce.

Ordinary zombies are difficult to mutate, and their mutation is not a job change, but a tendency to protect themselves.

It is not wrong to say that the second-level defensive zombies are one in ten thousand, but this is not the key, the key is that Su Chen did not know that the second-level defensive zombies were scarce at that time, and when he was in the hardware wholesale market, he encountered the second-level defensive zombies!

That was the only time he met, at that time he obviously had the strength to kill it, but he was afraid that he would miss the opportunity due to lack of energy, presumably the hardware wholesale market had changed greatly, even if Su Chen went now, I am afraid that he would not encounter a second encounter.

Heaven has already given Su Chen a chance, and the second chance may require excellent luck, so Su Chen can only wait quietly.

The possibility of advancing to level 4 immunity is zero, but it is a good choice to kill more level 1 zombies and fill up the experience to increase your strength and use experience potions.

Not being able to advance does not mean that Su Chen's strength will stand still, once Su Chen has accumulated full experience, his strength will at least increase a little.

Even if it is inconspicuous in strength, it can play a decisive role in a decisive battle.

After determining this, Su Chen asked Xiaoying to retreat to a hundred meters away from the Hell Two-Headed Dog to stand by, believing that even if the perception and vision of the Hell Two-Headed Dog were good, they would be useless in front of such a level of corpses.

Su Chen has many ways to deal with zombies, and the easiest way is to throw a miniature grenade outside the bell tower.

With such a dense crowd of corpses, a single miniature grenade can bring a very considerable number of casualties.

The stock of miniature grenades is currently relatively rich, but it is purely a waste to use one less to deal with this group of first-level zombies.

Su Chen walked downstairs quickly, changed his equipment again on the tenth floor, and then continued to go down continuously, not stopping until the second floor.

In the window on the second floor, Su Chen didn't need to aim at all, he only needed to lower the muzzle of the gun slightly, no matter how he shot, he would always be able to hit the target.

During Su Chen's shooting, sometimes zombies jumped to him from the window on the second floor and the broken ladder entrance, Su Chen held AK47 in his right hand and kept shooting at the target outside the bell tower, holding a Nepalese saber in his left hand, and the zombies who dared to approach him fell to the ground.

Under Su Chen's firepower, the zombies closest to the periphery of the bell tower kept falling to the ground, and then more zombies stepped on their corpses, and the zombies piled up zombies, piling higher and higher.

Su Chen suddenly found that he was helping the zombies by doing this, according to this situation, the corpses of the zombies would soon pile up two or three meters high, and they could easily jump in from the second-floor window, or even the third-floor window!

There are also seven molding charges on the tenth floor, which can blow up the stairway from the third floor to the ninth floor.

However, just two molding charges blew up the first and second floors, and there were small problems with the entire bell tower, maybe Su Chen could blow up the three stairways, but once the fourth floor was blown up, the bell tower would definitely collapse partially, or even collapse as a whole.

Su Chen had no choice but to shift the muzzle of the gun first and target the zombie group that was fifty meters away from the bell tower.

The group of corpses fifty meters away was still pushing each other, Su Chen couldn't kill them with one hit, but killing the zombies fifty meters away would at least not make them a stepping stone to the bell tower.

There are zombies climbing through the high walls of Dragon City all the time, and the safety of the bell tower is only temporary.

At the edge of the bell tower, the living and dead zombies have been piled up two meters high with their bodies, and even ordinary first-level zombies can easily climb in through the window.

Su Chen had to retreat to the third floor and continue shooting.

According to the current progress, in a minimum of twenty minutes and a maximum of one hour, the height of the zombie accumulation can reach five meters, and at that time, ordinary zombies may be able to climb through the window on the third floor.

At that time, the cushioning effect of the blown first floor and the second staircase was declared to be over.

Su Chen did not hesitate, and while shooting the zombies, he used the walkie-talkie to give a new order to Cassel on the tenth floor, asking him to rush to the third floor with the molding charge.

Su Chen wasn't sure how the battle between him and the Hellhounds would end, and he had to blow up the three-staircase to create more opportunities and time for the team.

For blowing up the bell staircase, at first many people did not agree to blow up the second staircase, for fear that the bell tower would collapse, but now if they know the situation, I am afraid that they will want to blow up to the eleventh floor.

Cassel's movements were very fast, the installation of the molding charge was very simple, Su Chen was already able to determine that no matter where it was installed, it would have a drastic impact on the bell tower, he simply didn't think about it, stuck it somewhere in the corridor at will, and then pressed the button.

With a soft sound, the whole bell tower shook violently again, this time, there were even cracks on the wall of the first floor, and the bell tower that was not completely renovated could not withstand this blow at all, and there were more and more cracks in the wall of the bell tower.

As long as there is no big movement inside the bell tower, the bell tower can support at least ten days and half a month, and if you are lucky, you can even support it for a few years.

Su Chen was sure that the bell tower was already loaded, and he definitely couldn't blow up the four staircases, otherwise the entire building would collapse, and all the survivors in the bell tower would die.

Blowing up the three stairways has bought Su Chen at least an hour, and the zombies need to be stacked eight meters high before ordinary first-level zombies can climb through the window.

The higher the height of the zombie pile, the more zombies need to be accumulated, judging from the current number of zombies, their number is fully capable of relying on the bell tower and stacking ten meters high!

Su Chen's attack on the Hellhounds was imperative.

Except for Su Chen, who has a way back, any survivor of Dragon City has no way back.

For the sake of Dragon City, for the sake of this group of survivors, whether he wants to or not, this battle must be fought.

AK47's magazine was changed again and again, and more and more first-class zombies died under Su Chen's gun.

In just ten minutes, Su Chen accumulated experience to 1000, and as the bullet continued to shoot, as explained by the zombie illustrated, Su Chen did not advance, but the experience was still accumulating.

The next battle may consume Su Chen's experience, Su Chen's current time is still free, he plans to accumulate more experience, and finally be able to encounter second-level defensive zombies in the battle.

In this way, he can level up in battle, and once he is promoted, even if three hell two-headed dogs with two heads are on it together, Su Chen thinks that he can kill them in seconds.

The barrel of AK47 is getting hotter and hotter, and the strong smell of gunpowder is lingering, Ye Yao has retreated to the fifth floor, Zhou Shan and his team have come to the sixth floor, and the other two teams have not changed for the time being.

After a while, Su Chen's brain once again heard a system prompt.

Player: Su Chen

Level: 3

Total experience: 1088

Experience required for the next level: 0

Skill: Treasure Eye, Variety Specialty

Special Ability: Gift, Wherever You Go

Items: AWM, M4A1, Micro Grenade

Title: Intermediate Immune, Junior All-round Warrior

Number of lit stars: thirty-one

Physical Strengthening: One Degree of Strengthening

First note: Twenty-four stars can be obtained by killing a level 3 mutant creature, and four have been accumulated so far

Second note: Killed Level 2 Agility Zombies, Level 2 Speed Zombies, and Level 2 Strength Zombies

System Prompt: If you are promoted to level 4 immunity, you will not be able to gain experience by killing a level 1 mutant creature.

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Su Chen's spirit perked up, and he would not be able to gain experience by killing a first-level mutant creature!

That's right, Su Chen, who has become a fourth-level immune person, in the face of a first-level mutant creature, isn't it an elephant crushing an ant, and he can still gain experience from an ant, wouldn't it be a risk-free score.

Fortunately, Su Chen did not kill the second-level defensive zombie at this time, otherwise Su Chen at this time would have been able to perfectly advance to the fourth-level immune person.

In this way, he will be able to easily solve this battle, but in turn, he will lose the way to gain experience by slaying down a level 1 mutant creature.

You must know that the most in this world will always be first-level creatures, once Su Chen loses the source of experience by killing first-level mutant creatures, he needs a huge amount of experience points to continue to advance, where should he go to get it.

Just as he was thinking, a system prompt came from his brain again.

This time, the system prompt is more simple and crude.

The main meaning of this system prompt is that once Su Chen is promoted to a fourth-level immune, it will take 25 points of experience to recover his energy and injuries, which will be converted into 100 points.

Energy regeneration has been changed from 20 points to 60 points, and wound recovery points have been changed from 10 points to 40 points.

Originally, there was a discount for energy and injury recovery together, but now not only is there no discount, but the amount of experience required has been greatly increased.

This is tantamount to a money grab!

I can't believe that if Su Chen at this time successfully advances to the fourth level of immunity, how much thought he needs to put into considering whether it is worth it or not if he uses the experience potion again.

After all, without the source of experience gained from killing first-level mutant creatures, Su Chen would not be able to deduct experience at will like now.

Fortunately, Su Chen didn't succeed in making the cut, so he could accumulate as much experience as possible before he killed the second-level defensive zombies.

Su Chen now knows why the system will prompt that the specified goal of promotion has not been reached at the beginning, and the experience will overflow, and now it seems that all the prompts in the system have their reasons.