As Xu Yi continued to go deeper, the surrounding karst cave tunnels also changed.

The first is the temperature, Xu Yi can clearly feel that as he goes deeper, the temperature in the karst tunnel begins to rise.

The feeling of being refreshing and relaxing on the surface also becomes heavy, and there is a faint smell of sulfur in the humid air, which makes people smell a feeling of chest tightness, shortness of breath, and difficulty breathing.

"Is there an underground river or a layer of magma ahead?"

Because the geography was unfamiliar, Xu Yi didn't dare to conclude what was ahead, or what the mantle world of this planet was like.

In particular, this is a planet that has been manipulated by humans with magnetic fields at the poles.

Xu Yi strode forward along the karst cave tunnel leading to the mantle layer, which seemed to be a small step, but he directly stepped out of the distance of more than ten meters, which was quite a bit of a shrinking of the ground.

As I walked, the color of the rock walls of the cave on both sides began to change, gradually starting to darken, and the light emitted by the fluorescent plants growing on them gradually became more and more red, red like flames.

"Gravity is starting to change, is this already in the mantle layer?"

Xu Yi slowed down, and a hint of surprise flashed in his eyes.

"The deeper you go underground, how does the oxygen content of this air get higher?"

When on the ground, Xu Yi estimates that the oxygen content of the air is about 13%, and when it comes to the ground, the oxygen content of the air is about the same as that of the real world.

Now Xu Yi clearly felt that when he took a breath, the energy from the oxidation reaction in his body was several times higher than that on the surface.

Is this the so-called "God's" means? ”

Thinking that this was all caused by the strong man named "Fengshen", Xu Yi's expression couldn't help but become solemn.

"...... Uproar"

Then I walked forward, and in the distance, the sound of running water came from nowhere.

Xu Yi's guess was right, there was indeed an underground river ahead.

"Bang Bang Bang Bang ......"

The sound of running water gradually became clear in Xu Yi's ears.

Bypassing a tunnel bend, the eyes suddenly opened up, and the originally low and oppressive karst cave tunnel suddenly rose up, and both sides became extremely open, making people have a sense of pleasure in climbing high and looking into the distance.

A few steps further on, a large river several hundred meters wide came into view.

The river flowed from Xu Yi's left to the right, and the river looked very gentle, only the clear but not noisy sound of flowing water came into Xu Yi's ears.

As far as the eye can see, the river water is crystal clear, and a large number of luminous aquatic plants grow at the bottom of the river, which almost illuminates the entire world under the river and clearly appears in front of Xu Yi.

If this is not the scene world, but the real world, maybe Xu Yi will take out his mobile phone, take a photo, post a circle of friends, and show off.

However, this is an alien planet in a world full of dangers.

The scene in front of him, although calm and beautiful, but under this calm beauty, there is an endless killing machine.

As soon as Xu Yi stood still on the bank of the river, he felt the pores of his body shrink, and a chill arose from the bottom of his heart, as if some terrifying creature was looking at him with the gaze of a predator.

With such a powerful physical attribute now, he could feel a sense of threat at this time, and you can imagine how terrifying the things hidden in the shadows were.

Xu Yi pretended to be calm and ignorant on the surface, but in fact, the qi and blood in his body were already running wildly, providing powerful power to his body.

Thanks to the fact that the oxygen content here is much higher than the surface, Xu Yicai did not show the exaggerated scene of inhaling like a whale swallowing and exhaling like a long exercise.

"Whoa...... Whoa......"

"Stepping on ......"

In the empty and deep karst cave tunnel, only the sound of the murmuring of the river and the footsteps of Xu Yi walking along the river flowed were left.

The surroundings are not too dark because of the relationship between fluorescent plants, but because the plants are too sparse, they are not too clear, as if shrouded in a layer of fiery red translucent tulle, which is both mysterious and enchanting.

Xu Yi was unaware of this, all his mind had been put into every corner of his body, trying to react the moment the opponent attacked.

As the sense of threat behind him became stronger and stronger, Xu Yi's footsteps became more and more natural, like walking on a broad road.

Suddenly, Xu Yi's body was still, completely stopped in place, and at the same time, the qi and blood of the whole body hugged the Dan Mixed Yuan, sinking and falling, like standing in the void, and the breath of the whole person completely disappeared.

Obviously, he was standing there, but if someone as strong as he closed his eyes and sensed it with his spirit, it was empty.

From movement to emptiness, this extremely extreme change made the unknown thing that firmly locked the spirit on Xu Yi's body suddenly startled, and his breath could no longer be restrained.

Less than ten meters behind Xu Yi, in the void air, ripples rippled, faintly revealing the outline of a strange beast.

Its lower body is the shape of an octopus's lower body tentacles, while its upper body is the head of a toad.

"Whoa......

At the moment when this beast was in action, Xu Yi seemed to have eyes on the back of his head, and he could see its position clearly. Then, the figure flashed, and it had already appeared in front of the beast, fitting and colliding.

"Boom ......"

Like a thunderbolt on a sunny day, Xu Yi's terrifying body like King Kong, with a domineering terrifying force, collided from stationary to almost teleporting, smashing the beast to pieces.

Even the air was smashed apart, and the place directly hit by Xu Yi became like a vacuum, forming countless cracks like glass cracks.

The wind from the impact formed a blade of wind that slashed at the rock wall on one side, on the ground, and on the river.

The beast's blue blood and broken meat sauce splattered everywhere, but soon vanished again, as invisible as it had been at the beginning.

Xu Yi's face changed, his body retreated suddenly, and in his original position, the outlines of countless tentacles appeared, and the space was shaken into endless ripples.

"Bang ......"

Xu Yi was hit in the back by a tentacle hidden behind him, and his body that had been retreating was suddenly blown back, Xu Yi's eyes were cold, and a large area of spatial ripples in front of him was shrouded, and the silhouette of a huge monster was faintly visible, as if it was opening its big mouth, waiting for Xu Yi's arrival.

"I don't know if I'm alive or dead."

Xu Yi's whole body became red, his muscles bulged slightly, and his voice became high and thick.

There is a deep murderous intent in his eyes,

"Dan Shape: Blood Dragon Body"

Xu Yi's whole body was shocked, and the qi and blood in his body flowed and operated at a special frequency, forming a circle of special fluctuations, hooking up the airflow vitality of the outside world, turning into a hideous blood-colored airflow dragon, winding around Xu Yi and circling up, and also opening his big mouth to bite the monster.