Eight hundred miles to the south outside the Xuanming City, there is a valley.

The dark red of the valley was not the color of blood, but the color of the heat burning.

There was a pungent smell in the air, it was the smell of sulfur, and there was a trace of heat, ordinary people couldn't get close to it at all, and they either died of poisoning or dehydration.

The cultivators of the Foundation Building Realm did not dare to approach, and they would also die.

Only by cultivating to reach the transcendent realm can you get close to here.

This is the location of the Earthfire Cave.

And the Earth Fire Cave happened to be mastered by the Gu Xuan Society.

The Gu Xuan Society's industry is all over the Xuan Netherworld, and there are naturally alchemists and refiners inside, etc., and this fire cave is a place for the Gu Xuan Society to refine weapons.

"Chen Shao, there is the Earth Fire Cave in front of you. A deacon of the Gu Xuan Society led the way, pointed to a hole in front of him with a red light flashing and said, the blazing heat was constantly diffusing from the hole, like the mouth of an open fire beast, as if it was about to burn everything.

The deacon of the Gu Xuan Society also didn't know why Chen Zong wanted to come here.

After all, the Earth Fire Cave is the place where the Gu Xuanhui refiners refine their weapons, the temperature is extremely hot, and it is even more full of fire poison, even those refiners who have entered the Holy Realm are not willing to stay for a long time.

After staying in the Earth Fire Cave for a few months, you must leave, recuperate for a month or two, and let the effects of the fire poison disappear before you can enter again.

A half-saint level, at most, is to stay in it for a few days.

I don't understand, I don't understand what the other party is going to do at all.

But Gu Xuanhui also intends to make friends with each other, after all, he is a Tianjiao with extremely high potential, so he has to obey the order.

On the contrary, after bringing the other party into the earth fire cave, there is nothing to do with himself.

Chen Zong followed the deacon of the Ancient Xuanhui into the Earth Fire Cave, and immediately felt that the temperature was rising, and the red light became more and more dazzling, as if there was an extremely fierce flame burning in front of him, as if he was about to burn himself to ashes.

However, this level of high temperature is nothing to himself, because he has the Purple Cloud Black Star Flame Body.

Although the Purple Cloud Black Star Flame does not play much of an amplifying role in his current strength, it is still good in resisting the high temperature.

Moreover, Chen Zong could also feel that the fire poison that permeated the Earth Fire Cave entered his body, and it was purified by the power of the Purple Cloud Black Star Flame, and he could not bring the slightest damage to his body.

In other words, Chen Zong can stay here for as long as he wants.

"Chen Shao, you have to be careful, don't enter the deepest part of the Earth Fire Cave, that Earth Fire Lake, the temperature is very terrifying, very dangerous. The deacon said solemnly.

"Good. Chen Zong nodded.

"Then I'll take my leave, and I'll pick you up in a few days. After the deacon finished speaking, he turned around and left, he had other things to do, and it was impossible for him to stay here with Chen Zong all the time.

Chen Zong looked around, this was a natural cave, a cave where earth and fire converged, there were many cone-shaped stones in it, either protruding from the ground, or hanging down from above, the red light was blazing, it looked like the inside of the mouth of an ancient fire beast, with interlaced canine teeth, boundless.

The refiners of the Gu Xuan Society naturally had their place, and Chen Zong would not bother, nor did he want to bother.

After looking at it, Chen Zong immediately took a step towards the deepest part of the Earth Fire Cave.

The purpose of entering the Earth Fire Cave was to enter the deepest part and use the power of its Earth Fire to cultivate the Three Tribulations.

Three Tribulations!

This secret method was created by a great saint realm supreme sword cultivator in the late stage, in order to sharpen the supreme sword intent.

The Three Tribulations are divided into three Tribulations, and the condition for cultivation is the half-step sword intent.

If you have already mastered the Dao intent of the sword and then come to cultivate, it will be a little slow, it will have an effect, but it will not be able to play to the extreme, and the higher the level of Dao intent, the worse the cultivation effect will be.

Basically, after the three turns of the Dao meaning, it is completely invalid.

The half-step sword intent level is the most suitable level for cultivating the three tribulations, at least, to practice the first tribulation, and then the two tribulations can wait until the half-step sword intent breaks through to the true sword intent and then cultivates.

It is also because the half-step sword intent cannot withstand the tempering of the second tribulation, let alone the stronger third tribulation.

Three Tribulations!

The three tribulations of this secret method are Earth Fire, Heavenly Wind, and Void Thunder.

Earth fire is the easiest to find, followed by heavenly wind, and void thunder is the most difficult to find.

As Chen Zong continued to go deeper, he could feel that the temperature was getting higher and higher, and gradually, the power of the Purple Cloud Black Star Flame was difficult to resist.

However, Chen Zong's body is strong, and he also has high heat and high temperature resistance, so he can still resist it.

Deep, deep, deep, deep.

The red light was extremely dazzling, shining in all directions, and it was very dazzling, making it difficult for Chen Zong to look directly, as if his eyes were being roasted on a fire.

Hot, hot, hot!

The heat that invades from the outside world is like the heat that burns the earth, and the heat that seems to turn itself into ashes.

Carrying this high temperature, Chen Zong walked forward and saw a small lake.

The small lake was only about fifty meters in circumference, and it was so red that it was extremely dazzling, and Chen Zong's eyes were difficult to open.

Earthfire Lake!

It was a lake formed by countless earth fires after countless years of continuous accumulation and precipitation, and the liquid that looked like red light flashed inside was not really liquid, but only condensed to an extremely high form, and it looked like a viscous liquid.

Such as magma.

On the surface of the Earth Fire Lake, there was also a faint layer of almost transparent flames burning, and Chen Zong could feel that layer of terrifying power that was almost void flames, even more terrifying than his own Purple Cloud Black Star Flame.

The Xuan Gu Fire Refining Technique was running, and the Purple Cloud Black Star Flame suddenly ran every part of the body in a mysterious trajectory, greatly resisting the terrifying high temperature brought about by the burning of the Earth Fire Lake, allowing Chen Zong to stay here for a longer time.

Then, he began to cultivate the Three Tribulations Sharpening Secret Method.

Fortunately, Chen Zong was able to divide his mind into two uses, otherwise the Xuan Gu Fire Refining Technique or the Three Tribulations Sharpening Secret Technique could only be operated by one.

Half-step sword intent, that is a kind of void power, different from spiritual power and semi-holy power.

Chen Zong ran the first tribulation of the three tribulations, and suddenly, a trace of earth fire qi was attracted, and he quickly entered Chen Zong's sea of knowledge, which was where the half-step sword intent was.

At the same time, the half-step sword intent was also condensed in the sea of knowledge.

The qi of earth and fire was extremely pure and extremely hot, and as soon as he entered the sea of knowledge, Chen Zong felt as if his sea of knowledge had been burned to ashes, and the pain was incomparable.

Chen Zong had to endure it.

The aura of earth fire spread rapidly, wrapping the condensed half-step sword intent and incinerating it continuously.

The severe pain became more and more intense, directly increasing several times, making Chen Zong feel fainting, but he had to support it to stay awake, otherwise, not only would it not have the effect of tempering, but it would burn the half-step sword intent, and he would no longer be able to comprehend the sword intent, and even his soul would be traumatized, which was very serious.

This price is indeed very amazing, but if you can practice the secret method of the Three Tribulations, you can forge the supreme sword intent, and the harvest is also amazing.

Chen Zong was speculating whether the so-called supreme meant transcending the high-level Dao meaning.

If so, that's amazing indeed.

No matter what, the secret method created by a Great Saint Realm supreme powerhouse in the late stage of sword cultivation is always extraordinary.

Wisps of earth fire qi were pulled one after another, and gradually floated into the sea of knowledge, wrapped in half-step sword intent, and constantly burned, as if calcining the sword embryo.

The burning of the high temperature made Chen Zong suffer great pain, directly impacting the pain of the soul, and there was a feeling that the soul was being roasted on the fire.

Withstand, and control, keep refining.

This is a fire catastrophe.

Disaster!

This is a calamity, and if you survive it, you will be reborn.

The half-step sword intent was burned by the qi of earth fire, and it seemed to be melting, and Chen Zong had to control it, constantly converging, which was very difficult and exhausting.

Without a strong enough mental will, it simply cannot be supported.

In other words, most cultivators would not be able to succeed in cultivating even if they obtained such a secret method as the Three Tribulations Sharpening Blade.

Gradually, Chen Zong withstood it and adapted to the high temperature.

This is just the beginning, absorbing more earth fire qi into the sea of knowledge, refining the half-step sword intent, under this tempering, the half-step sword intent seems to become more condensed.

Refine!

Refine!

Refine!

As more and more earth fire qi entered the sea of knowledge, it continued to condense, and gradually turned into a flame to burn, and the flame also continued to absorb the foreign earth fire qi, becoming stronger and stronger.

The first tribulation of the Three Tribulations is to use the earth fire to refine the half-step sword intent.

However, if a cultivator can't release the half-step sword intent and put it into the earth fire for a long time, then he can only go the opposite way and let the earth fire burn in his sea of consciousness.

How to start a fire in the sea?

The sword cultivator of the strongest person in the Great Sage Realm had a whim, and he used wisps of absorption of the qi of earth fire, starting from the most subtle beginning, accumulating little by little, and improving little by little, so that he could continue to bear and adapt, until finally, when the qi of earth fire was sufficient, it could be condensed into a flame, and then it could be continuously absorbed to become a real earth fire.

In this way, it can be regarded as truly refining the half-step sword intent with earth fire.

It took half a day for Chen Zongfang to absorb enough earth fire qi and form earth fire in the sea of knowledge.

As soon as the earth fire appeared, Chen Zong felt as if his sea of consciousness was about to be burned, and even his soul trembled under the heat.

Terrifying to the extreme, if you are not careful, the sea of knowledge will be destroyed by this terrifying earth fire, and even the soul will be burned to ashes.

Exquisite mastery!

And the Three Tribulations Sharpening Blade is incomparably exquisite, as long as Chen Zong continues to operate, as long as Chen Zong's spiritual will can support it, he can resist the calcination of the earth fire, so as to continuously refine the half-step sword intent.

It's like casting an iron block into a sword embryo.

Time passed slowly, and an earth fire continued to burn in the sea of knowledge, constantly calcining the half-step sword intent, and with the burning of the earth fire, the half-step sword intent gradually became more condensed.

This is the depths of the Earth Fire Cave, and most of the time, no one will come, but occasionally strong people will appear.

At this moment, an old man in a fiery red robe flew over, and when he saw Chen Zong, he was shocked.

Because he felt Chen Zong's aura fluctuate.

High-level semi-saint level!

When did the high-level semi-saint level also come here to cultivate, didn't he kill himself?

The old man's hair was fiery red, and under the light of the fire of the Earth Fire Lake, it seemed to be a burning flame, and he stared at Chen Zong, as if he wanted to see through Chen Zong's emptiness and reality.