In three days, he successfully broke through the sixth-layer forging bone of the Mortal Realm, and the bone condensed was the most powerful silver bone, if he let outsiders know, he would definitely be scared to death.

For ordinary martial artists, it takes months to refine white bones, and with the assistance of a large number of precious pills, they can succeed. Not to mention the red and silver bones.

But Ling Feng was still very dissatisfied, because the time given to him was too little.

At this moment, as Ling Feng broke through the sixth layer of the Mortal Realm, the lethality brought to him by the Gangfeng and Heavenly Fire at the mouth of the Broken Soul Cliff had been greatly reduced.

An Nai couldn't help but have a strong curiosity in his heart, and Ling Feng planned to pass through the Broken Soul Cliff and enter the sea of bitterness to find out.

Holding his breath, he strode towards the depths of the Broken Soul Cliff.

The punishment was a total of seven days, and the remaining four days, Ling Feng planned to use these four days to try to see if he could break through the seventh layer of blood condensation in the Mortal Realm.

After ordinary martial artists break through the sixth layer, the blood line in the body begins to condense, the potential of the person is limited, and the blood line will not exceed nine in general, if it is exceeded, every time one is added, the qi and blood that are hit will be stronger by one point, and the power will naturally be more amazing.

In the end, the potential in the body was forced to the limit, and then the condensed blood line was like a rope twisted, fused together again, even if it reached the threshold of the seventh layer of the Mortal Realm.

Ling Feng set a bottom line for himself, at the very least, the blood lines he condensed must exceed nine, or even more.

Through the mouth of the cliff, what appeared in front of Ling Feng was a row of green daisy stone walls, which stood high in the river and were baked by the setting sun to become a colorful barrier.

Under the hundreds. It is a vast river.

The river is tumbling, extremely dense, and the color is brownish-yellow.

"This water?"

Ling Feng's heart moved.

This river under the cliff. It definitely doesn't get dense for no reason, and at the bottom of the river, there must be some hidden secrets.

Ling Feng's curiosity was aroused, and he was about to fly down the cliff when he suddenly noticed a sign standing under the cliff.

It is engraved with the words 'The bitter sea is boundless, and the shore is turned back'.

"What is the boundless sea of bitterness?"

Ling Feng laughed at himself, in his previous life, he had never seen any wind and waves. How can you be frightened by just a few words?

But he was still secretly careful, and his feet moved. Like an eagle, it flew down the cliff.

When his body was about to touch the water, Ling Feng suddenly stretched out his hand on the mountain wall to stabilize the falling figure. Then hurriedly looked down.

Above the surface of the river, the river water is tumbling, extremely turbid, dense like paste, and there is a faint trace of decay coming out.

Ling Feng was extremely vigilant, and with his other hand he tore off a branch that grew out of a crack in the rocks and threw it into the river.

The broken branch floated above the river, and it didn't look strange at all.

Ling Feng relieved himself and jumped into the brown water.

The situation has changed dramatically!

The brownish water has a strong stickiness. Tied up Ling Feng's body and dragged him to the bottom of the water.

Ling Feng secretly said that it was not good, and his limbs danced wildly. Struggled to get out of the water.

However, there seemed to be countless invisible tentacles in these brownish waters, which were holding Ling Feng to the death, and for a while, he couldn't break free.

I saw that the turbid brownish water was about to flood my head.

Ling Feng made a quick decision. Hands in the middle of the cliff, like a gecko. Climb up slowly.

With his head above the water and the smell of fresh air, Ling Feng secretly breathed a sigh of relief.

Fortunately, Ling Feng is now on the edge of the cliff, and there is still a point of borrowing, otherwise the consequences will be unpredictable.

This brownish water contains a huge amount of mixed energy, which is extremely strange. With the strength of his own body, he was almost devoured by it.

Ling Feng could feel that the viscosity in this brownish water was extremely fierce, and it was many times more powerful than ordinary mire.

"How did the students of the Divine Martial Academy who entered the power of this place survive this river?"

Ling Feng suddenly pondered.

Could it be that he relied on the strength of the flesh to swim all the way to the end of the river?

Ling Feng immediately discarded this ridiculous idea.

With the strength of Ling Feng's current physical body, he couldn't swim in this brown water unharmed, and it was naturally impossible for other Mortal Realm martial artists to do it.

Unless the students who come to practice are all cultivators in the late stage of the Juyuan Realm, they can fly in the air and fly directly to the end of the river.

However, the hundreds of thousands of students of the Shenwu Academy, every time they come in to practice, in addition to the Heaven Rank class, those students in the late stage of the Juyuan Realm, there must also be students of the Earth Realm class of the Mortal Realm, so this possibility can also be ruled out.

Ling Feng's eyes turned sharply, and he immediately had other methods.

He climbed a cliff and cut down several centuries-old trees with a knife in his palm.

Remove the branches and leaves and bark, flatten the heart of the tree, and tie it into a rudimentary model of a boat.

Moving the boat to the brown water, as Ling Feng expected, the boat could float freely, without interference, without the slightest pulling force.

"Could it be that this brownish water is designed to devour living creatures?"

Ling Feng wondered.

Standing on the boat, beating gently, it looks like the boat I built myself is quite sturdy.

Ling Feng found a few more bundles of rattan grass from the cliff wall, twisted them into ropes and put them beside him, just in case.

When it was ready, the boat was windless and automatic, and it took the initiative to row forward, which made Ling Feng stunned for a moment.

Ling Feng sat on the boat and surveyed the surrounding environment.

I saw that there were cliffs on both sides, like dogs' teeth intertwined, pointing straight to the sky, making people unconsciously produce a sense of insignificance.

This big river seemed to have no end, for two days in a row, Ling Feng sat in a small boat and drifted with the current, still unable to see the source.

"It's not the way to go on like this!"

Ling Feng muttered.

Seven days, five days have been wasted now, and there is not even a blood line condensed in his body, if he can't find a way to condense the blood line, he can only waste the next time in vain.

Ling Feng stared at the dirty water in a daze, and a flash of inspiration flashed in his mind.

He tied the rope to himself, tied the other end to the boat, and jumped into the brown water.

"Plop!"

The strong stickiness pulled Ling Feng down.

Ling Feng inhaled sharply, and whenever the brown water was about to flood his head, he swung his body frantically, slamming his palms on the water, and his body rose with force.

In this way, for a while, you can really keep yourself from being swallowed up by brown water.

But the price was that he had to keep his limbs active at all times, and if he stopped a little, he would die in the brown water.

Ling Feng's hands and feet brought up a trace of afterimage, and the speed was not clear at all, and the dense brown yellow water splashed several meters high.

In less than an hour, Ling Feng was so tired and sweaty that he almost collapsed, he grabbed the rope and desperately climbed onto the boat, panting.

After strenuous exercise, the potential of Ling Feng's body was also stimulated bit by bit.

He felt a burst of burning heat in any part of his body, as if it was burning, and his blood circulation was countless times faster than usual.

The benefits of this are also initially revealed, the blood flows wildly, and there is too much vitality and vitality contained in it, which gradually coagulates into a blood line.

After resting for a while, Ling Feng immediately jumped into the brown water and frantically tempered his body.

An hour!

Two hours!

Ten hours!

Sixteen hours!

As the day passed, Ling Feng held on to the brown water for longer and longer.

He can now move in the brown water for more than ten hours without relying on external objects, without being swallowed by the brown water.

And while the strength of the physical body is also increasing, the blood lines are also constantly condensing, and in one day, three blood lines have been condensed.

Whenever he condensed a new blood line, he felt that his whole person contained majestic vitality and strength, and his qi and blood soared wildly...... The strength has been greatly improved. (