It's just that as soon as Zhang Zichen walked to the gate of the castle, something strange happened.

"What's wrong? Why do I feel the ground shaking slightly?"

Zhang Zichen immediately stopped and carefully felt the movement on the ground.

The sky, the miserable white sun, shining on the yellow sand, was very quiet.

At this time, there was not even the sound of wind in the air.

Everything around, very, very quiet.

But suddenly, the ground shook slightly.

There was a thud, and the castle moved, and the sand on the ground shook.

Zhang Zichen frowned, and a feeling of uneasiness came from the depths of the earth.

"I feel like there's a huge demon living deep underground, and it's trying to break free!"

Zhang Zichen muttered to himself.

However, before Zhang Zichen could think about it, the ground shook again.

Boom!

Zhang Zichen moved, the castle moved, the ground moved, and the sand trembled.

After a few breaths, Zhang Zichen's soles made another thumping sound.

This time the shaking was obviously louder and more violent than the previous ones.

"There must be some living creature down here!"

Zhang Zichen was surprised, but his face revealed a hint of joy: "Since there is a living creature trapped in this underground, it is very likely to be a Chaos Beast!"

Thinking of this, Zhang Zichen showed a happy smile on his face.

Boom!

Suddenly, the ground shook again.

This time the shaking was much stronger than the previous one.

Zhang Zichen glanced around, and finally decided to exit the castle first.

What is the underground thing, Zhang Zichen is not clear for the time being.

But Zhang Zichen knew very well that the power of this underground thing was very powerful, otherwise, it would not have been able to shake the entire ground so violently.

And just when Zhang Zichen stepped back twenty zhang, the ground shook continuously.

Boom!

Knock knock!

Knock knock knock!

This vibration, like the sound of a person's heartbeat, beats faster and faster.

The sand on the ground jumped higher and higher.

After a while, the entire space was sprayed like a fountain, spraying high.

"Stand back!"

Zhang Zichen immediately felt that taking twenty zhang back was not enough, so he stepped back another fifty zhang.

However, fifty zhang was not enough, so he retreated more than a hundred zhang.

It wasn't until he stood in the distance, the vibration was much quieter, that Zhang Zichen stopped and quietly looked at the situation in the castle in the distance.

The sand around the castle jumps up and down as if it's dancing.

But the shaking wasn't over.

With the sound of a bang, Zhang Zichen was surprised to find that the walls of the castle in the sand began to collapse.

With a few snaps, the whole castle cracked, and finally turned into sand, which merged with the yellow sand of the ground.

"What kind of monster the hell?"

"If this monster is a Chaos Beast, then it must be very powerful! I can't kill it!"

The big action of the underground monster made Zhang Zichen start to be a little worried, because the power of this monster seemed to be more powerful than he imagined.

If this was really a powerful Chaos Beast, then even Zhang Zichen would not be its opponent.

Time goes on.

The shaking of the ground became more and more frequent, and the sand on the ground churned and danced.

Suddenly, however, the ground around him began to sink in.

The surrounding sand seemed to be sucked into the ground by an invisible force.

Rustle!

The flow of sand creates a huge whirlpool.

They're frantically flowing underground.

In just the blink of an eye, a huge black hole appeared in the place where the castle in the sand was originally located!

All the sand here is gone.

"What's going on?"

With this doubt, Zhang Zichen slowly approached the huge black hole.

Coming to the edge of the black hole, Zhang Zichen raised his eyes to look under the black hole.

Inside the huge black hole, except for the sound of falling sand around it, it was pitch black, there was nothing, nothing could be seen.

However, Zhang Zichen could feel that under this black hole, there seemed to be something that wanted to rush up.

Under the black hole, there was silence for a while.

And just when Zhang Zichen was puzzled, suddenly, there was a clangling sound from under the black hole.

"It's ...... It's like the sound of chains crashing!"

Zhang Zichen quickly determined that this must be the sound of chains colliding.

His conjecture was soon confirmed.

Because at this moment, a yellow mass suddenly rushed out from under the black hole.

Rustle!

The strange mass rushed upwards with a rustling sound in its mouth.

"What a strong force!"

Zhang Zichen immediately stood on his heels and stepped back twenty feet.

At this moment, only a roar was heard at the entrance of the cave, and a huge monster rushed out of the hole.

This monster is all yellow and sand, and it looks like a caterpillar.

However, Zhang Zichen felt that it was more like a huge spring silkworm!

And what exposes the black hole is just a head of this 'giant silkworm'.

On the head of this 'giant silkworm', Zhang Zichen saw twelve eyes, and these twelve eyes actually grew on the neck of the 'giant silkworm'.

"What is this?"

Zhang Zichen was confused.

"This ...... Could it be the primeval xenomorph Chaos Beast?"

Although the appearance and statement of this chaos beast are somewhat different from Meng Po's, overall, there is still not much difference.

Indeed, it does look like a giant caterpillar.

"Rustle!"

After the appearance of this 'giant silkworm', the yellow skin on its body agitated, it has no mouth, but it can make a rustling sound, which is very strange.

And this voice pierced Zhang Zichen's eardrums.

"It's too powerful! Its cultivation is at least above the Saint Monarch realm! I'm not its opponent at all!"

Zhang Zichen used his true qi to block his ears to prevent his eardrums from being punctured by this sharp rustling sound.

Although this monster only showed a head, its head was several times larger than the castle just now.

One can imagine how long its waist must be under the black hole.

This monster also seemed to see Zhang Zichen, it suddenly blew out a breath, and in an instant, the surrounding sand immediately formed a sharp sword, stabbing at Zhang Zichen.

Zhang Zichen was shocked, and his face changed suddenly.

This monster, cultivated above the Saint Monarch realm, moved its fingers slightly, and Zhang Zichen was going to die ugly.

Not to mention, this breath.

Whoosh!

In the entire space, countless sharp swords composed of yellow sand came to Zhang Zichen's eyes in the blink of an eye.

Although Zhang Zichen knew that he was not the opponent of this monster, out of the instinct to live, Zhang Zichen immediately mobilized the true qi in his body and injected it into the Black Crystal Divine Sword.

At the same time, swing a sword.

With a hum, the Black Sand Excalibur carried tremendous power and stabbed at him with hundreds of yellow sand swords.

Rumble!

The two forces collided, and Zhang Zichen, who thought that he would be seriously injured by the shock, found his strength and easily destroyed those yellow sand swords.