Murong Yu didn't know what kind of ore this war knife was made of, and he didn't know how the artifact should be conceived, but he felt that with a dark corrosive aura, the blade was pitch black, as if it had been eroded by the dark element.

In fact, with Murong Yu's current strength, if he wants to give full play to the power of a medium-grade artifact, he still needs to go further, but with this artifact, Murong Yu has hope, and he will naturally work harder.

In the space ring of the king of the metal clan, Murong Yu found the thing he dreamed of, the heart of life of the metal tree, and he didn't expect that such a good thing was prepared in this king's ring.

Under the guidance of Jin Shi, Murong Yu began to absorb this ball-sized heart of life. Before absorbing it, Murong Yu found a hidden cave, turned on the golden stone guard, and did his own defense before taking out this heart of life.

The left hand held up the heart of life, and a flame rose in the palm of the hand, and the heart of life seemed to begin to melt slowly under the high temperature. Seeing that it was almost over, Murong Yu cut the fingers of his right hand, allowing his blood to slowly merge with the blood-red liquid flowing down.

As the heart of life melted, Murong Yu's bloodline began to absorb the molten liquid, and the blood-red liquid slowly absorbed into the body along Murong Yu's bloodline.

Murong Yu felt that his blood veins were slowly condensing, and a powerful metallic sense in the golden blood was densely filled with blood veins, and the originally thin blood veins were gradually thickening, as if they were coated with a layer of metal.

Strong power must be delivered by strong blood vessels, and the thickness of the blood vessel walls affects the energy transmitted. The Heart of Life of the Metal Tree has the miraculous effect of thickening the blood veins.

As the walls of the blood vessels thickened, Murong Yu felt that the power he would convey in the future was slowly increasing, and the energy transmitted in the blood was also slowly increasing, and with the absorption of the Heart of Life, the bones that were originally shining with golden light actually began to change color and turned into dark gold.

Continuing to absorb, Murong Yu's sea of qi, qi veins, demon caves, and demon veins were all advancing, and the sea of qi and demon caves were churning, and the powerful fighting qi and magic power were tumbling endlessly. And the teleportation speed of the qi veins and demon veins accelerated sharply, making Murong Yu feel full of power.

The body, which was originally stronger than the giant dragon, was actually gradually mutating, and the human body was always a short board, with Murong Yu's cultivation. The physical fitness finally headed towards a heinous place, until Murong Yu felt as if he had turned into a fighting machine.

The blood of the golden pith, the veins of the golden pith, the bones of the golden marrow, the whole body turned into a dark golden piece from the inside out, shining with golden light.

Murong Yu was overjoyed, and immediately threw himself into the comprehension and derivation of the mystical comprehension of the golden system, and he suddenly found that his affinity for the golden element had increased again, and at this rate, the speed of the mystical comprehension of the golden system law would increase exponentially.

Murong Yu didn't use the Living Spirit Wood anymore, it was because he had already absorbed a lot before, and this great tonic had not been completely digested, absorbed, and consolidated before. It's best to take your time with your feet on the ground, and the Dream Ice Soul Sword is now well-fed and is also transforming.

Murong Yu fell into cultivation again, and the last three mysteries of the gold system began to slowly open the door, and Murong Yu was like a lost child groping his way forward on the path of the law mysteries.

Time flies like a white horse. In the past two years, Murong Yu's Golden Law Mysteries have fully blossomed, and his strength has skyrocketed.

Opening a pair of golden eyes, a golden light pierced through the mist, like a divine light sprinkled down, Murong Yu felt that the world began to change slowly, and everything in front of him became hazy.

Until he saw everything in front of him. Only then did I find that I was actually in the underground world, and it was pitch black all around, if it weren't for the mysteries of the gold system, it was estimated that there would be a problem even seeing the surroundings clearly.

This is a wide underground cavern with a radius of hundreds of miles, and there is an underground swamp at the foot of it, and he is actually on the edge of the swamp. In the far side of the swamp, an underground river flows.

A dark, cold, terrifying aura struck, and in the dark swamp, dark creatures popped out of their heads and mixed in the black mud. Rushing towards Murong Yu.

This is the Dark World! And it's the Underground Dark World! Murong Yu instantly understood.

As the most evil of all the elements, the dark elemental power possesses a powerful destructive power, even more powerful than the destructive power of light magic. It's only because the light system restrains the dark system that it will be slightly higher in the ranking.

On the other side of the dark swamp is a dark underground stone forest, the stone forest is uneven, estimated to be ten to thirty meters high, obviously, in that dark stone forest, there are also dark creatures.

Murong Yu rose up, and a ball of fire in his hand shot out, illuminating the entire underground world, and at this moment, he found that he seemed to have fallen into the encirclement.

In the mud below, the dark swamp emitted a foul smell, and many dark creatures let out a low roar, which was creepy, and the stomach juice was tumbling.

Murong Yu's body accelerated in the air, flying towards the lower reaches of the underground river, the Changhong Sunset Sword slashed through the sky, dense flying dark creatures fell one after another, and there was a roaring and biting sound of snatching and foraging in the mud.

These dark flying creatures are not big, estimated to be twice as large as ordinary bats, and their strength is not very strong, under Murong Yu's divine sword, they scattered and fled in all directions, and the "puff" wings fluttered in the entire cave.

Before he could move forward for three hundred meters, countless black mud pillars rose, blocking Murong Yu's way. People are animals who love cleanliness, and Murong Yu is no exception, hundreds of bucket-thick mud pillars suddenly rose in front of him, and Murong Yu naturally dodged backwards.

With a flash in the air, Murong Yu retreated, his body dodging continuously in the air, only to avoid the rising mud pillar, his eyes bursting with golden light, staring at the bubbling swamp water.

A pair of long sharp horns emerged, Murong Yu's pupils contracted for a while, and he flew back again, judging from the swamp range in front of him, Murong Yu estimated that it was a huge dark creature.

"Roar!" a thirty-meter-tall monster slammed to its feet, as if it had slept well in the dark swamp, and stretched out its strong and powerful arms.

Looking at the humanoid mutant monster that was still half of its body sunk in the swamp, Murong Yu couldn't help frowning, the body was a horse's head, and it was still holding two pointed horns, and its big mouth almost occupied half of its face.

What kind of monster is this?Is it a dark creature?Murong Yu secretly looked at this monster that had risen from the swamp.

Facing this low-level dark creature, Murong Yu's eyes flashed with a golden light, and the Changhong Sunset Sword slashed through the sky and stabbed at the monster's head. At Murong Yu's speed now, almost in a flash, the divine sword had already stabbed the monster.

The power of a hundredfold fighting spirit was integrated into the mystery of the fire explosion, and the monster's head exploded in an instant with a "boom!", like a firework blooming in the dark. Murong Yu sneered twice, thinking that he dared to come out and stand in his way with this strength.

The deafening explosion was particularly harsh in the entire dark world, the sound echoed for a long time, Murong Yu suddenly felt that he had done something wrong, in this dark world, there must be many sleeping monsters, and if he made an earth-shattering scene, he would inevitably wake up more monsters.

"Alas, why am I so stupid?" Murong Yu muttered to himself, he had already heard a lot of movement coming from the front and back.

It's useless to regret it now, and it's best to use your speed to get out of here as soon as possible. Murong Yu accelerated, his body swept through the air, and under the induction of the "Ice Heart Shocking Wind" and the Soul Divine Sense, he avoided those dark creatures who woke up as much as possible.

"Whoosh" Murong Yu was as fast as lightning, and swept towards the lower reaches of the underground river, and many dark creatures along the way let out earth-shattering roars.

Continuously advancing, Murong Yu suddenly found that a big mountain appeared in front of him, blocking the way, and this moving mountain blocked Murong Yu's way. Under Murong Yu's perception, he suddenly felt cold all over, like falling into an ice cave.

A group of dark creatures had obviously appeared in front of him, and with the help of a little blue light over the swamp, coupled with Murong Yu's super eyesight, he had already seen a bunch of monsters in front of him.

If Murong Yu guessed correctly, this is the Shadow Heartsnatcher in the Dark World, this kind of monster lives in the underground dark world, and is known for stealing people's minds, and it is a very terrifying monster.

The body seemed to be covered with a thick layer of rotten mud, more than twenty meters high like the burly body of a mountain giant, the strong arms were bulging, like a black python scurrying, and the sharp claws were actually flashing a little cold light in such a dark environment.

This giant-like abyssal demon has long, slender tentacles that possess keen detection and can release a poisonous mist that does not need to breathe, but rather penetrates.

As long as the skin touches, they can penetrate and enter, which is unpredictable, and their combat power is also quite strong, it is estimated that this group of Shadow Mind Flayers is at least saint-level or sub-god-level.

The dense behemoth monsters blocked Murong Yu's way, and even if they used spatial teleportation, it was estimated that they would teleport into their crowd. Relying on their powerful dark perceptions, they seem to have locked down the daredevils who have intruded into their world.

"Bang Bang Bang" Several Shadow Mind Snatchers ran towards Murong Yu, trampling the rotten swamp with their thick legs, Murong Yu only felt a disgusting wave of qi rushing towards him, and his hair stood up and floated backwards.

The Golden Stone Guardian Armor had always been blessed on his body, but now in order to prevent the dark poisonous mist of the Shadow Soul Snatcher, Murong Yu had to bless the Dou Qi and Magic Power Protector, for fear that he would be accidentally poisoned. In this dark world, once he is poisoned, there is no one to save him, so Murong Yu is very careful.

ps：

Murong Yu entered the dark world, and a big battle was inevitable!