Previously, he dived into the pond, the deepest part of the pond was about four or five meters, the depth was not as calm as the surface of the pond, the water was turbulent, Tang Chen was caught off guard, and was almost washed away by the current.

He managed to find the water outlet.

The water outlet is not far from the stone bridge, close to the junction of the kitchen and the stone bridge.

There is a hole with a diameter of less than one meter at the bottom of the pool, and the entrance of the hole is dark and deep, like the throat of a monster, and a large amount of pool water is sucked into it and disappears into the darkness in an instant.

After his breathing was evenly adjusted, Tang Chen dived into the bottom of the pool again, carefully exploring along the pool wall, and the location of the water inlet was quickly determined. Tang Chen didn't stop, he continued to search around the pool wall, until he confirmed that there was only one outlet and inlet in the pool, and then climbed up and lay down on the stone bridge to rest.

At this point, he was able to draw a general conclusion.

This is supposed to be a dark river flowing through the belly of the mountain.

It is very likely that the dark river will eventually connect to the outside rivers or lakes, but it is impossible to estimate how many places it will eventually flow before it joins the rivers and lakes, depending on the route of the dark river. The best result is a flat river, but, if you're unlucky, it's not surprising to make a bend in the belly of the mountain.

One thing is certain: if you go down the dark river, there may be hope of getting out of the valley!

After experiencing the blows of the Heavenly Ladder Plan and repairing the broken teleportation array one after another, finding a way out of the valley from the waterway became another hope for Tang Chen to get out of trouble. Once a thought comes to mind, it can no longer be erased.

Tang Chen's fighting spirit is burning!

Tang Chen picked up a burnt torch and used charcoal from memory to draw the nearby terrain on the stone bridge.

In order to catch the grass rabbit, he had studied the terrain of the Dadong Mountain Range, looking for a safe route to the grass peak, so as not to be killed by the spirit beast halfway through, and the Dadong Mountain Topographic Map Yu Jian is still in his Qiankun bag. But the accuracy of that jade slip is not too high, although the large terrain is basically not wrong, and the details can only be added by Tang Chen himself. Fortunately, he had the experience of squatting on the peak, and for more than ten days, Tang Chen could only lie in a hidden place most of the time, looking at the scenery near and far under the peak to kill time.

He quickly restored the nearby terrain to a rough approximation.

The cave is deep in the belly of the mountain, and the road is tortuous and winding, Tang Chen is difficult to accurately locate the location of the cave, he can only use the grass peak as a reference point. Since I don't know the general trend of the dark river, it seems to be westward now, and after a few turns in the belly of the mountain, it is likely to finally emerge from the east, and it is a very unreliable thing to speculate in which direction the dark river will connect with the aboveground water system from the current flow direction, and Tang Chen will not do that useless work.

With Caoke Peak as the center, there are two rivers and five lakes within a radius of 10 kilometers.

The nearest river is only 3,000 meters from the Grass Peak, and the other is about 5,000 meters. The lakes are more widely distributed, the nearest one is under the Caoke Peak, the other four lakes are all five thousand meters away, and the farthest one is ten kilometers away, almost beyond the maximum range set by Tang Chen.

There are many rivers and lakes nearby, and the possibility of getting out of trouble from the dark river has undoubtedly increased, and the most ideal result is that the dark river leads directly to the lake under the Caoke Peak, followed by the river three thousand meters away, Tang Chen is eager to try.

However, there are also great risks associated with walking in the dark river, such as breathing problems, being pushed by the current and hitting rocks, whether you will encounter an underground waterfall, and whether there are any hostile creatures in the dark river...... Any of these risks can be fatal, some can be solved, and some can only be bet on luck.

Tang Chen quickly made a decision.

Take a gamble!

There was no hope of repairing the teleportation array, and the Ladder Path did not have enough resources to support it, so it was impossible to succeed, and the danger of the Dark River was nothing compared to the risk of making a hole in the cliff with a wooden stick. Of course, he could also do nothing, in the valley until the end of his life, but as soon as this choice appeared in his mind, he was ruthlessly ruled out by Tang Chen.

Brother is young, and An can live to the end of his life!

Brother has to eat all the world's food!

Brother hasn't dated yet......

Tang Chen began to refine his plan to minimize the risk as much as possible.

Take out a bundle of rattan rope and tie one end to the stone table, the other end still tied around the waist. Turned out a few gourds for holding water, poured out the water inside, tightened the bottle mouth, and put them back into the Qiankun bag one by one. After doing all this, Tang Chen jumped into the pool and dived to the water outlet.

He didn't hesitate to dive in.

After entering the water outlet, Tang Chen felt as if he had been vigorously pushed from behind, and the speed of the water suddenly accelerated, pushing him forward quickly, until a strong force came from his waist. The rattan rope had been put to the end, and there was still darkness in front of Tang Chen.

"Damn! so long?"

Tang Chen cursed in his heart, and immediately turned around and retreated the way he came.

This was tantamount to fighting against the turbulent water, Tang Chen grabbed the rattan rope with both hands, kicked the bottom of the dark river with both feet, and went up the river step by step, and it took a lot of effort to get rid of the suction of the water outlet and return to the cave.

After resting for a while, and after his strength recovered, Tang Chen took out all the remaining rattan ropes in the Qiankun bag, untied the rattan rope around his waist, and knotted it with another rattan rope. He took a night pearl from the wall of the cave before returning to the pool, tied the rope back to his waist, and jumped down again.

Sinking to the bottom of the water, Tang Chen took out the Night Pearl, the bright light emitted by the Night Pearl was as faint as a candle in the wind, which could only make Tang Chen barely see half a meter away, but it was better than having black eyes like before.

Entering the water outlet again, Tang Chen had become accustomed to the suction in the cave, his body curled up, his hands holding his head, his divine consciousness released, and he let the water flow lead him into the depths of darkness. When the rattan rope was tightened again, Tang Chen repeated his old trick, lying on the bottom of the water with his hands and feet, resisting the impact of the current and walking back. When he walked about three meters away, he suddenly stopped and stood up cautiously.

"Boom!"

His head hit the stone and made a soft noise, but Tang Chen laughed happily.

"There is nothing wrong with the Divine Sense, there is indeed a piece of this place that has not been flooded and can be used as a ventilation point. ”

Qi refining cultivators are still unable to use internal breath, and they usually have nothing, but the underwater environment is greatly affected. With the ventilation point, Tang Chen's stay in the dark river could be extended.

Tang Chen already had a preliminary plan, he decided to explore the Dark River as much as possible, if conditions permitted, he would tie a rattan rope to the ventilation point, and the length of the rattan rope would depend on the distance between the two ventilation points. Tang Chen hoped to divide the dark river into small sections with ventilation points like a relay, and fight steadily and steadily, step by step, until he left the mountainside or the relay could not continue!

It's not easy, but it can certainly reduce the risk.

Compared with the ladder plan, the dark river channel is much more operable.

Tang Chen quickly dived back to the bottom.

The first ventilation point is only two meters square, and it is a confined space isolated by water and rocks, and it is difficult to replenish the oxygen in it after it is consumed. Tang Chen didn't want to waste precious air in vain, although his body's demand for oxygen increased when he went against the water, he had another way.

Taking out a gourd and unscrewing the cork, Tang Chen quickly stuffed the mouth of the bottle into his mouth.

"Coo", an extra string of bubbles in the dark river.