As the morning sun rises in the east, small black dots fly from afar, and these black dots become more and more, and finally converge into a dark cloud.

Countless vampire bats are flying back to the habitat from all directions, hovering outside the mouth of the cave on the mountainside, and then flying into the hole in an orderly manner.

On another hill more than 300 meters outside the cave, Charles was eating breakfast while frowning and observing the cave, and things were a little unexpected to him.

When he came, he found that the entrance of this karst cave was about 70 meters high and 60 meters wide, and it slowly extended into the mountain for a hundred meters like a trumpet, and then quickly shrunk.

Assuming that a vampire bat needs 20×20cm of space to hang upside down on the roof of the cave, then 25 bats can be hung in one square meter.

Suppose that the area at the top of the cave is 60×100m, and there are at least 150,000 bats in it.

Judging from the vampire bat he caught last night, a vampire bat weighs about 600 grams, and each bat weighs about ?? They have to suck out at least 30 tons of blood in a night.

Considering that the radius of vampire bats in one night is 20 kilometers, it will not take long for the animals in the surrounding area of more than 100 square kilometers to be wiped out, and it is only a matter of time before they enter villages and towns to attack humans like they did last night.

This was a bit beyond Charles's expectations, and the headmaster gave a clear explanation of the situation, and at first he thought that the cave was only thirty or forty meters high and wide, so that at least it could be cleaned up with rockets.

Now the cave space is too large, there are too many bats, there are not enough rockets to carry, and the long-distance attack methods such as "Ru's Treasure", pea shooter, and corn cannon are used to startle the bat swarm, and the bats that pour out in an instant are likely to exceed the fire projection intensity, and after the bats in front block the attack, the bats in the rear will break through the defense line.

You can't wipe out all the vampire bats at once, and if they escape, they'll harm other places.

Charles thought about it, let's make a miracle vigorously.

In the battle of capturing the necromantic at the Space Gate, he once cast a wall of fire tens of meters long, more than ten meters wide, and several meters high, and this wall composed of extremely pure fire elements instantly burned a team of necromantic knights to ashes.

Here, the wall of fire can be flattened to 70 meters high, 60 meters wide, and half a meter thick, so that the vampire bats can be blocked and burned to death, and by the way, the cave can be detoxified.

He remembered that bats carry a large number of bacteria and viruses, and if they are not properly disinfected, they will be a source of disease infection.

So he put on his suit again, put it on his back with an oxygen tank, and teleported to the Batcave.

He opened the "Soul Vision", and the dense bats connected on the interface.

At this time, there was another moth, and a string of light spots appeared behind him on the interface, and when he looked back, a large team of nearly 100 people was walking far away.

Mosquito legs are also meat, and the experience value of vampire bats is also experience value, and besides, it is more than 100,000 numbers, which should be enough for him to rise to level 51.

Since he burned his soul with chaos in Chapter 903 and sublimated his soul with chaos in chaos, his strength has further improved, although the number of levels has not changed, he has changed from blue to purple, stepping up a new level.

Now that he has been promoted to the next level, the strength of his body to be fed back is extremely impressive.

But this kind of thing is personal privacy and will not be told to others.

Now that someone comes to steal experience, it is naturally not allowed.

The hand is fast, the hand is slow, and Charles immediately began to use magic.

There are a large number of wind and water elements around the cave, as well as some earth elements, in addition to a large number of basic elements that can only be felt by a few people.

The spiritual power that was so strong that it was foul spread out in all directions, and the spiritual power grabbed the basic elements one by one, and then affected them, making them become extremely pure fire elements.

A few hundred meters away, a crusade of knights and soldiers in the castle led by the brave man and his companions suddenly stopped, and a fiery red fire element suddenly appeared outside the cave entrance, startling them.

These fire elements quickly gathered together to form a wall of fire as clear as a jewel, blocking the entrance to the cave.

White smoke began to rise from the area around the cave where it came into contact with the wall of fire, and the limestone that made up the mountain was heated and decomposed, releasing a large amount of carbon dioxide, and the quicklime produced was falling down.

The plants on the side were also dried in an instant, and then they were burned.

Charles could feel that the vampire bats at the entrance of the cave were already feeling bad, they were flying in shock, and the sound of arms fluttering could be heard behind the wall of fire.

He began to manipulate the half-meter-thick wall of fire to push five centimeters per second into the depths of the cave, ensuring that every part of the cave was sterilized by high temperature for ten seconds.

Those vampire bats that were startled by the heat flew around, and many bats crashed into each other in the air.

It didn't take long for Charles to see piles of gray-white ash appear on the ground, which were burned by vampire bats that had fallen on the ground.

Not long after, the quicklime on the top and sides of the cave began to fall down, and the cave was instantly white.

The wall of fire pushed forward slowly but surely, and countless vampire bats flew towards the depths of the cavern, but there was a dead end.

Charles's consumption is large, but he replenishes while consuming under the recovery of the "battlefield perpetual motion machine", and the absolute consumption is within an acceptable range.

The cave warrior rushed over with his companions, and looked at the white cave outside the entrance in amazement, the scorching air rushed towards him, and he didn't know whether to advance or retreat for a while.

Charles ignored them and went about his business.

At this moment, a vampire bat king with a wingspan of ten meters rushed out from the depths of the cave, its body emitting a blood-red light.

Realizing that it had to flee today, it sucked the blood of many of its kind, accumulating energy and trying to break through the deadly wall of fire.

Charles didn't discover it because the density of bats here was so great that the souls of ordinary bats were connected together to hide its existence.

It's just that the Vampire Bat King underestimated the temperature of the wall of fire, and the people on the other side of the wall only saw a flame flying out of the wall and then falling to the ground, burning alone.

Charles continued to move forward slowly, the crystal clear wall of fire burning every space until the cave came to an end.

At the end of the cave there is a passage that leads to the depths, several meters wide.

Charles dispersed the wall of fire and got inside.

A dozen or so vampire bats also entered, which were killed with fireballs by Charles as he chased in.

Deep in the cave is an underground river, pitch black, and it is not known where it leads.

He took out his lamp and looked around, and then found a row of steps on the bank of the underground river, leading to the upper reaches of the underground river.

These steps carved out of the rock look like no one has walked for a long time, and some stalactites have been erected on them.

Without hesitation, he walked down the steps.