I only reached the Foundation Establishment stage at eighty years old, and then the system appeared.

After Yang Hongbo and his companion exited the entrance to the secret realm, they discovered that a temporary trading area had been set up outside. Not only were people selling spiritual herbs and demon cores obtained from the secret realm, but merchants were also buying and selling items from within the secret realm.

Ignoring the blatant stares from the crowd in the market, Yang Hongbo led Yang Tian towards the Central Region. Although they were already on the outskirts of the Central Region, it would still be billions of miles to truly enter it; the Human Emperor Continent was indeed vast.

On the outskirts of this central region, one can see a large city with tens of millions of people appearing from time to time, almost within a radius of more than 100,000 miles. Moreover, next to each large city is a forest of monsters with a radius of tens of thousands to more than 100,000 miles.

Each monster forest supports a city with tens of millions to hundreds of millions of people. Moreover, there are monsters in the monster forests that have reached the Tribulation Transcending stage. They have signed an agreement with the human race's Tribulation Transcending stage experts, allowing human cultivators below the eighth rank to enter the monster forests and kill monsters below the eighth rank, but they cannot cause extensive damage to the monster forest environment.

The Central Region is incredibly rich in resources. Fourth and fifth-grade spiritual herbs can be found everywhere in the Monster Forest, and spiritual veins and mineral deposits are frequently discovered. The more dangerous a place is, the richer its mineral treasures tend to be.

That day, Yang Hongbo led Yang Tian to the edge of a huge monster forest. Cultivators frequently entered and exited the area. Outside this monster forest, which spanned over 100,000 square miles, there was not only a giant city with a population of over 100 million, but also several trading markets around the monster forest.

Yang Hongbo and Yang Tian landed together at the entrance of a market. The market was surrounded by a seventh-level protective shield, which wasn't much to them, but they couldn't just destroy it upon arrival. The two entered the market and searched the stalls for any treasures worth buying.

Just then, they heard people discussing something: "Hey bro, did you know? A ghost cave has appeared in the Monster Forest."

"I heard there are tenth-grade spiritual herbs in this cave, but it's also full of strange demonic beasts. Almost everyone who went in before us died, and those who escaped were all covered in wounds!"

"According to those who escaped, the place is filled with a cold wind that devours spiritual energy. Without the replenishment of spiritual energy, the physical body alone cannot withstand the attacks of the monsters inside."

Yang Hongbo and Yang Tian exchanged a glance, and Yang Hongbo said, "Yang Tian, ​​let's go over there and observe the situation before making a decision!"

"Yes, Master!"

The two flew to the location of the cave. A large number of cultivators had already gathered in front of the cave entrance. Every now and then, people would form teams to enter the cave, but almost all of them disappeared silently. A couple of people escaped, covered in injuries, but they had all cultivated physical body tempering techniques.

Yang Hongbo frowned slightly as he looked at the people who had escaped. He said to Yang Tian, ​​"It seems that the danger in this cave is far greater than we imagined. The eerie wind devoured the spiritual energy, preventing cultivators from using spells. They could only rely on their physical strength to fight against the monsters. No wonder the casualties were so heavy."

Yang Tian nodded, a hint of worry flashing in his eyes: "Master, should we still go in? With our strength, although we're not afraid of those demonic beasts, that eerie wind..."

Yang Hongbo pondered for a moment and said, "Tenth-grade spiritual herbs are extremely valuable and worth a try. However, we cannot be careless. Yang Tian, ​​you go into my secret realm first. I am wearing a Chaos Spiritual Treasure, which can resist the devouring of that Yin Wind. I will go in to scout the situation, and if I am confident, I will call you out."

Upon hearing this, Yang Tian nodded without hesitation and replied, "Yes, Master, be careful."

With a thought, Yang Hongbo took Yang Tian into his secret realm. Then, a flash of light appeared on his body, and a top-tier Chaos Treasure—the Human Emperor Bell—appeared above his head, emitting a faint glow that enveloped his entire body. This Human Emperor Bell was something he had obtained through a lottery; it could resist all spiritual energy devouring and soul attacks, making it an excellent treasure for exploring unknown and dangerous places.

After preparing everything, Yang Hongbo took a deep breath and stepped into the cave.

Upon entering the cave, a chilling aura assaulted his senses, as if countless tiny needles were pricking his skin. Yang Hongbo activated the Human Emperor Bell to protect his entire body, instantly shutting out the chilling aura. He looked around and saw that the cave was dimly lit, with only occasional flashes of spiritual light illuminating the path ahead.

"This yin wind is indeed powerful. If it weren't for the Imperial Bell, my spiritual energy would probably have been devoured." Yang Hongbo thought to himself with a sense of vigilance as he continued to explore forward.

Inside the cave, the path twisted and turned, sometimes wide, sometimes narrow. Yang Hongbo proceeded cautiously, constantly watching his surroundings. Suddenly, a deep roar came from ahead, followed by a lion-tiger with bull horns rushing out of the darkness, heading straight for Yang Hongbo.

"A sixth-tier demonic beast!" Yang Hongbo's eyes relaxed. It was only a sixth-tier demonic beast, but there was nothing to be afraid of. He dodged the lion-tiger's attack with a flash. The lion-tiger did not give up after missing its first attack and pounced again. At the same time, several more similar demonic beasts surrounded it from all directions.

"It seems these demonic beasts don't use spiritual energy, relying solely on their physical strength," Yang Hongbo thought to himself. He condensed chaotic power in his hand, transforming it into a long sword, and faced the demonic beasts.

Sword light flashed, and the demonic beasts were all cut down, some even killed outright. Yang Hongbo did not stop, continuing forward. He knew that even more powerful demonic beasts awaited him deeper into the cave.

As they ventured deeper, the number and strength of the monsters increased. Yang Hongbo encountered cows and sheep with claws, crocodiles with wings, moose with six legs... These monsters were bizarre and varied, but they all had one thing in common: they did not use spiritual energy, relying solely on their physical strength.

"These demonic beasts seem to be affected by that yin wind, unable to use spiritual energy and only able to rely on their physical strength," Yang Hongbo guessed, becoming even more cautious. He knew that although these demonic beasts couldn't use spiritual energy, their physical strength was exceptionally powerful, and if he was careless, he might suffer.

After slaying wave after wave of monsters, Yang Hongbo finally arrived at the depths of the cave. This cave was like a secret realm, spanning thousands of miles, with enormous stalactite pillars supporting the entire cave.

Here, the eerie winds grew even fiercer, as if threatening to devour everything. Yang Hongbo circulated his chaotic power to protect his entire body, while his eyes blazed as he searched for the legendary tenth-tier spiritual herb.

Suddenly, his gaze fell upon a stone wall, where a spiritual herb, emitting a faint glow, was quietly growing. That herb was one of his targets on this journey—a tenth-tier spiritual herb!

However, just as he was about to step forward to pick them, an even more violent gust of cold wind swept in, and at the same time, a huge monster emerged from the darkness. The monster was as large as a mountain, with three eyes, each emitting an eerie light.

"A peak seventh-tier demonic beast!" Yang Hongbo's heart skipped a beat. He knew that this demonic beast's strength was close to the eighth tier, making it the strongest opponent he had encountered on this trip.

The monster looked at Yang Hongbo, let out a deafening roar, and then pounced. Yang Hongbo dodged the attack with a swift movement, and at the same time, swung his longsword at the monster.

The sword light and the claw shadows of the demonic beast intertwined, producing a series of metallic clangs. Yang Hongbo and the demonic beast were locked in fierce combat, and for a time, neither could gain the upper hand.

The biggest drawback of this cave is that magic cannot be used. Once a spell leaves the body, its spiritual energy is swallowed up by the yin wind, rendering it ineffective. Therefore, Yang Hongbo can only use his physical strength to fight against the monsters.