The structure and layout of the third floor are no different from the second floor, and they still look like these hotel rooms. The second floor we considered did not gain much, so we didn’t search the third floor carefully.

After everyone killed all the zombies on the third floor, they went straight to the fourth floor.

The structure of the fourth floor is somewhat different from that of the third floor and the second floor. Although it is also various rooms next to the corridor, these rooms are no longer places to rest, but are similar to functional facilities such as conference rooms, offices, etc. There are also some zombies wandering in these places, but they are all ordinary zombies, so they do not pose any major threat to everyone.

The imagined mutant zombies have not appeared, and the team members are both glad and disappointed. Fortunately, there is no mutant zombies, so there will be no loss of personnel, but at the same time, they have lost the opportunity to advance to level 5.

Judging from Liu Gan’s previous arrangements, there should be a sequence in his mind. As long as he encounters enough mutant zombies, he will sooner or later advance to level 5, right?

Continue down the stairs. When you go down to the fifth floor, you can hear the creepy roar below just standing at the entrance of the stairs. It sounds like there are many zombies below, at least dozens of them. Some of the timid team members looked at Liu Gan in fear, worried that there would be any danger below suddenly rushed over, and everyone could not hide in the narrow corridor.

Liu Gan stopped Zhang Shengli and Wang Decheng, and then walked in the front with Yinhe. After going down the stairs, only two zombies rushed over. They were wearing security uniforms, and it seemed that they were guarding the entrance before the disaster.

Since there were only two zombies, Liu Gan and Yinhe easily solved them. After turning on the emergency lights on this floor, they finally saw clearly what the dozens of zombies were going on. After the stairs went down, there was an empty room, similar to a security check. Going forward, this was a very solid iron gate, with dozens of zombies wearing white coats or other clothes trapped on the other side of the iron gate.

The iron gates are locked, so although their number is terrifying, they do not pose any threat to everyone. After seeing the team members come down, dozens of zombies roar and try to hit the iron gate, wanting to rush over or squeeze in to bite everyone.

But it was obvious that all this was futile, because the iron gate was very strong. The iron gate they just kept shaking could not push it down or open.

Killing zombies through the iron gate is the most loving thing. The other team members consciously left the opportunity to Li Miao, the weakest in the team. Li Miao used a spear made by Zhang Shengli, with a sharp dagger tied to the front and stabbed the zombies inside through the iron gate. As the zombies fell down one by one, a faint black mist floated out of the zombies one by one and drilled into her body, enhancing her strength bit by bit.

Liu Gan was not in a hurry. Anyway, he had time, so he let the team rest on the spot, waiting for Li Miao to slowly stab all the dozens of zombies to death.

After killing all the zombies opposite the iron fence, Li Miao shook the iron fence hard and made a loud noise. She wanted to attract the zombies deeper behind the iron fence. This tactic does have some effect. Soon, some scattered zombies ran up from the depths of the ground and crawled over the previous pile of corpses and rushed to the edge of the iron fence.

But with their pitiful IQ, they just kept rushing against the iron fence like wild animals. Then they were stabbed to the ground one by one by Li Miao on the iron fence, becoming her experience value for strengthening her strength.

When new zombies no longer appeared on the iron fence, the zombies' zombies had almost blocked the entire passage. Zhang Shengli then walked over and opened the iron fence door with the keys found from the two security guards.

I don’t know what the mutation process of these people was like when the disaster occurred, but it is possible that the two security guards outside turned into zombies first, so they didn’t even have time to open the iron gate and release the inside.

If the people inside were mutated first, the two security guards should not be staying here anymore. They may have gone to the ground to report the letter. Of course, it is also possible that there was a mutated first in the iron gate. The two security guards were sent to guard the iron gate and somehow became zombies.

No matter what the reason is, the underground has become like this anyway, so it doesn’t make sense to figure out these things out, so there is no need to dig into anything.

"What kind of research do you think is being conducted underground to lock all these researchers in the basement?" Wang Decheng asked Zhang Shengli.

"I can't guess this, I will know it if I go on." Zhang Shengli replied to Wang Decheng. While talking, the team members dragged away the zombies that blocked the passage and cleared the road in.

After entering, looking at the layout of the laboratories on both sides of the corridor, everyone quickly confirmed that this place should be a biological laboratory, with various iron cages containing various animals of different sizes. Most of the animals have died, and only a small part of them are still moving.

But these small animals looked very manic, with blood-red eyes. After seeing everyone coming in, they frantically hit the cage. Fortunately, the cage rods that locked them were very thick, so they could not rush out to attack everyone.

There are also some laboratories with a few anatomical celebrations. In addition to the corpses of some animals, there are even human corpses. Now they are all rotten and even maggots become stinking. Obviously, they have been a while.

Seeing these things deep underground, although we knew that these dead objects would not attack humans, the team members still showed a look of fear and discomfort on their faces. In particular, the local survivors felt even worse. They could see that these experiments were obviously underway before the catastrophe. Maybe the catastrophes of the whole world were related to these experiments.

Apart from the disgusting animals, human corpses, and some related experimental equipment and drugs, there is still nothing to gain on this floor, nor has it encountered powerful waves such as mutant zombies. A downward staircase appeared at the end of the laboratory corridor. It seems that the underground space is much deeper than everyone imagined.

At this depth, it probably exceeded the depth at the bottom of the river. The construction of this laboratory was indeed a big project.

Go down the stairs and down another floor, there is still a laboratory. This floor looks more like a slaughterhouse, which is different from the previous floor. Most of the corpses of animals on the anatomy bed are human corpses. (To be continued...)
Chapter completed!