Li Wei sensed a movement in the Book of Ten Thousand Laws.

He didn't immediately summon the Book of Ten Thousand Laws. Even though, after the battle, the workers and lackeys, whether they were workers or Skeleton Gang members, had all scattered, there might still be someone hiding and watching.

Moreover, although the police station in the lower district was more of a façade, it wasn't entirely non-existent. If he wasted too much time here, and the police arrived, things could become very troublesome.

He picked up the vampire's heart that he had just thrown away. This time, he still had lingering fears. Before understanding the situation, he didn't plan to directly touch the heart with his own body again.

Taking off his jacket, Li Wei wrapped the heart in it and carefully picked it up.

Hmm, this time nothing unexpected happened.

...

Leaving the crime scene, Li Wei didn't immediately go to submit the task. Instead, he returned to his residence.

First, he tended to his wounds. The weakness persisted, but it was better than before.

Confirming that the injuries wouldn't have a severe impact, and a few days of rest would likely lead to a full recovery, he couldn't wait to study the vampire's heart.

He summoned the Book of Ten Thousand Laws, skipping the chapters about the Sharingan, Transformation Technique, and Steel-Cutting Flash, and arrived at the fourth page.

The fourth page, which should have been entirely blank, now displayed some strange patterns faintly. These patterns were too light, too subtle, and incomplete. They seemed to resist being deciphered by some mysterious force.

No one could recognize what was written there. However, Li Wei was familiar with this situation—it was the process of the Book of Ten Thousand Laws revealing new abilities. In the past, this process had always been quick; within a few breaths, a blank page would be filled with entirely new text. However, this time, it seemed that the absorbed power was weak, unable to generate a new page directly, leading to this situation.

Did this mean that continuing to input life force would reveal new abilities?

After some thought, Li Wei didn't dare to inject his own life force directly. He didn't want to experience being drained again. The first time he used the Book of Ten Thousand Laws to obtain the Sharingan, without a foundation of gene fluid, he would have been sucked dry if not for his luck.

Taking a deep breath, he picked up the vampire's heart with his bare hands, maintaining the summoned state of the Book of Ten Thousand Laws.

Slowly, he saw fresh blood oozing out of the vampire's heart, falling into his palm and being absorbed into the skin.

This time, he carefully felt the changes in his body. He sensed a force moving with the blood entering his palm, flowing into his chest, and then disappearing mysteriously. At the same time, the content on the fourth page of the Book of Ten Thousand Laws was continuously expanding and becoming clearer.

This process lasted for about five minutes. The vampire's heart he held in his hand had completely withered. The cold touch disappeared entirely, replaced by the sensation of squeezing dry mud lacking moisture. With a little force, the whole heart crumbled in his hand.

Apparently, the valuable vampire's heart, which could be used as the main material for manufacturing C-grade gene fluid, had lost all its value.

In its place, a page full of strange characters appeared on the fourth page of the Book of Ten Thousand Laws.

This surprised Li Wei—could the heart of a vampire unseal the pages?

With a turn of his thoughts, he quickly thought of a possibility.

The Book of Ten Thousand Laws essentially used life force as a source to unseal its pages. This life force had to come from Li Wei himself.

However, there was a fundamental difference between supplying it himself and having to use his life force.

In the case of using gene fluid, it was as if the power of the gene fluid was injected into the Book of Ten Thousand Laws before being absorbed by his body. In this process, his body acted like a transit station, and his life force wasn't entirely absorbed by the Book of Ten Thousand Laws.

On the other hand, the heart of a vampire, being the flesh and blood core of such a magical creature, inherently contained a considerable amount of life force. In Li Wei's hands, it seemed like the blood and flesh core could be directly used by the Book of Ten Thousand Laws.

The life force in this blood and flesh core was comparable to gene fluid of the same level, if not better. After all, no matter how sophisticated the manufacturing process was, there would always be some loss of life force. Considering the addition of some ingredients in gene fluid, the two could roughly be on par.

But regardless, the fresh life force contained in a blood and flesh core was undoubtedly more abundant.

Ordinary people had to use gene fluid, as they couldn't directly absorb the life force from magical creature flesh and blood cores. Li Wei was no exception.

But the Book of Ten Thousand Laws could. It seemed that injecting the life force from a magical creature's flesh and blood core into the Book of Ten Thousand Laws was more advantageous for him.

Untreated blood and flesh cores of the same level were much cheaper than gene fluid.

In any case, this was a great piece of news. It meant that the ways for Li Wei to improve his strength had become broader!

Excited, Li Wei focused his attention back on the Book of Ten Thousand Laws, which had just absorbed life force.

The Book of Ten Thousand Laws, now filled with flowery characters on the fourth page, represented three options in Li Wei's eyes.

One was upgrading the Sharingan, the second was upgrading the Transformation Technique, and the third was acquiring a new ability called the Devil's Left Hand.

The second option was decisively ruled out. As an auxiliary ability, the Transformation Technique had special value, but it couldn't directly enhance his strength. Its effectiveness was limited, and precious ability upgrades weren't suitable for this.

So, the choice had to be made between upgrading the Sharingan and acquiring the Devil's Left Hand.

The Sharingan was undoubtedly a very powerful ability. In the original anime, it could be considered overpowered.

However, to truly reach an overpowered level with the Sharingan, it needed to be upgraded to the Mangekyo Sharingan at least. The Sharingan before the Mangekyo, while possessing powerful visual reconnaissance abilities and some genjutsu skills, and resistance to genjutsu, didn't significantly surpass normal abilities overall.

As for the Devil's Left Hand, this new ability intrigued Li Wei.

It was an ability that could permanently transform his left hand into a demonic form. The Devil's Left Hand would significantly enhance Li Wei's strength and showcase multiple special abilities exclusive to the demonic hand.

Looking at the reference image in the Book of Ten Thousand Laws, Li Wei recognized that the Devil's Left Hand came from the game "Devil May Cry 4," belonging to one of the two main characters, Nero. However, in the original game, it was supposed to be the right hand, and he didn't know why it became the left hand in the Book of Ten Thousand Laws.

But that didn't affect his interest.

After some thought, he decided to choose the Devil's Left Hand.

The Book of Ten Thousand Laws' upgrade, revealing new abilities, seemed somewhat like a lottery to Li Wei. Fortunately, he wasn't unlucky, but seeing two mediocre abilities appearing during the second unsealing of the pages, he couldn't be considered extremely lucky.

In this situation, since a powerful ability could appear during the unsealing of the fourth page, he preferred to obtain it first.

As for the upgrade of the Sharingan, there would be opportunities in the future.

After making the choice, he quickly felt a change in his body.

A slight tingling sensation manifested on his left arm. He saw a faint blue light surging beneath the skin from his elbow to his fingertips.

Soon, that slight tingling sensation turned into a burning sensation, then progressed to a scorching pain, as if his entire forearm, palm, and fingers were being directly roasted on a flame.

Up to this point, Li Wei could endure, but when that burning sensation intensified further, as if his entire forearm, palm, and fingers were being grilled directly on hot water, it became challenging for him to endure.

Drops of cold sweat appeared on his forehead, veins bulged on his neck, his face turned red, and he clenched his teeth, enduring the pain with all his might.

However, this wasn't the end. The pain in his left hand continued to intensify until he couldn't bear it anymore—it didn't stop until he was nearly unable to endure the excruciating pain!

Li Wei clutched his left hand, howling in agony! He felt he was almost about to pass out from the pain, but his consciousness was clearer than ever.

Until he thought he might not survive this kind of pain, that it might directly cause his death, the excruciating sensation gradually subsided.

Lying weakly on the ground, he spent a full hour recovering some strength.

Lifting his left arm, it had completely transformed into a different appearance.