After He Lin teleported away from the Reef Island, he didn't waste any more time and went directly to the source of the demon invasion that he had obtained when he communicated with the Heavenly Dao when he was promoted to the Tyrant Realm.

The North Sea, the world's most dangerous sea, is home to a variety of powerful sea monsters from ancient times. The barrier surrounding the sea is even more powerful than that of the East Sea.

However, this barrier does not prohibit the entry and exit of humans, nor does it prohibit the entry and exit of sea monsters. However, once the sea monsters leave the North Sea, they will be punished by heaven and die.

Therefore, no sea monster will leave the North Sea.

The function of this barrier is very simple, which is to eliminate the lock of the heaven and prevent the coming of heavenly punishment.

The North Sea is equivalent to a cage for sea monsters, imprisoning the sea monsters that survived the ancient times in the North Sea.

However, the world has changed dramatically, and this world is no longer suitable for sea monsters to survive. Even if the North Sea is the last refuge for sea monsters, it cannot change the world and their living environment.

As time went by, sea monsters slowly died of old age or weakness, but no new sea monsters were born. The number of sea monsters became smaller and smaller, and they were almost on the verge of extinction.

However, even so, the North Sea is still a very dangerous area for humans because the powerful sea monster that supports the North Sea barrier still exists.

Its existence prevented humans from entering the North Sea on a large scale and hunting sea monsters.

Its power is stronger than all the powerful Tyrant Realm masters! If there is no heavenly punishment outside the North Sea, it can definitely dominate the world. Where is the space for human existence?

But over the years, many people still risk their lives to steal the bodies of sea monsters or hunt dying sea monsters.

He Lin recalled the information he had seen in the Hunter Guild's memory jellyfish, and looked at the huge black turtle in front of him with a diameter of nearly a thousand miles. This overlord of the North Sea was a powerful existence like a magic needle that could calm the mind.

At this time, the black turtle was dying, and a strange tree was growing in the center of its back.

The strange tree is as black as ink, but it looks like metal. Its bark is like scales, its branches are like bones, and its leaves are like human faces wailing in pain. On the branches and between the leaves, there are fruits of different sizes that look like beating hearts.

He Lin crossed the space in one step and came to the front of the strange tree. The strange tree shook slightly, but did not actively attack. He Lin placed his right hand on the strange tree and unexpectedly received a message from the Demon Lord.

"New Lord of the Origin Realm, your system is extremely useful to me. In return, I will give up invading this world and allow you to complete your mission with ease. Of course, I know this won't be enough to compensate for the cost of analyzing your system, so I've left this Demonic Origin Tree as my return gift. I hope it will be of some use to you."

He Lin discovered that he had control over the "Devil's Origin Tree." A quick inspection revealed no traps.

"This Demon Lord isn't evil at all! He seems very easy to talk to and very principled. But, his personality is too good. Isn't there some hidden danger that I'm not aware of?"

Herling spent a month carefully checking it out before he was sure that there were no hidden dangers.

"That is, this thing itself is problematic! But it's like a treasure, right in front of me. I can pick it up just by bending down. How could I let it go?"

Anyway, this world is just a clone of consciousness, and Helin is not a creature from the Heavenly Dao Realm, but the master of the Origin Realm. In this world, he is an immortal existence.

There is no danger of falling!

"As for the other hidden dangers, I'm just studying and learning from them. If I don't use them, what's the hidden danger? If there are hidden dangers in studying the things that dominate the Abyss, they would have already been there when I was studying the Heart Demon Mirror. I don't care about this anymore."

Having put aside his worries, Herlin began to study the "Devil's Source Wood".

The "Demon Source Wood" grows on the back of the black turtle, but it seems to grow in a different space, constantly devouring the spiritual energy between heaven and earth, and devouring the deeper origin of the world.

And after being swallowed, the fruit that is produced is the devil fruit!

After the devil fruit on the "Devil Source Tree" matures, it will be randomly teleported to a piece of land in this world the moment it lands, waiting to be discovered, devoured, and then transformed into a devil.

Why devil fruits can be randomly transmitted through the land, why devils are afraid of sea water, why devils can possess the inherited memories of dead devils, why devil fruits can transform humans into devils, and so on, these questions were continuously analyzed as Herlin's research deepened.

The more I study, the more I am shocked by the knowledge, laws and applications contained in the Demon Source Wood!

"The Devil Lord should specialize in the laws of biochemistry, capable of creating such biochemical weapons. They can parasitize the bodies of the world's most powerful beings, consuming the spiritual energy of heaven and earth through their bodies, and through their 'Tao', devouring the essence of the world, transforming into Devil Fruits. And Devil Fruits can transform humans into Demons. Demons with the characteristics of this world."

"The magical powers of devil fruits are also deeply connected to the parasites they inhabit. The reason why devil fruits in this world are randomly transported to islands around the world through the ground after landing is because the Black Turtle is a sea monster of the Dominant Realm with the Earth Attribute. It controls the Earth Attribute, space, and other laws of heaven and earth. The devil fruits inherit this magical power, which is why they have these magical functions."

"This is also the reason why demons are afraid of water. The earth element is too heavily influenced by the laws of heaven and earth, and the restrictions placed on demons by heaven have caused them to deeply dislike water and even develop an instinctive fear of seawater. However, this is merely an instinctive aversion and fear, not to the point of becoming weakened by encountering seawater, or even forced into a restriction."

"The Devil's Origin Tree is the mother tree of Devil Fruits and also serves as a signal relay station. When a demon dies, the demon's mark returns to the Devil's Origin Tree, naturally bringing back all the memories and inheritance before death. The Devil's Origin Tree then sends them to all the demons and Devil Fruits in the world, replenishing the inherited memories and improving the demon's strength and survivability."

As for the technology of transforming humans into demons, while it has some unique features, it's not amazing. Herling can transform the host's body into a digital form, eliminating various fatal or disabling weaknesses that originally existed in humans.

"What's truly astonishing is that the Demon Lord can actually mass-produce Devil Fruits that transform demons! What they've refined isn't a magical tool resembling a Devil Fruit, but a magical tool that produces Devil Fruits. Such designs, such knowledge, such technology, and such magical powers are truly priceless treasures!"

"With this knowledge and technology, my system can break through the limitations of the host being an individual! I can also experiment with many of my ideas again."