Villain: Ultimate Mutation System in the Alternate World

The vibrations from his now lightning-charged hands ensured his bones wouldn't touch the stone directly.

Slowly but surely, the rune started vibrating. This time, the stand where it sat didn't react.

As the sparks touched the rune, it was lifted by the magnetic field created by all the electricity.

Carefully, he guided it out of the stand.

His mind raced as the rune hovered in his grasp, suspended by the energy flowing through him.

The control needed to be precise, maintaining the delicate balance to keep the rune from falling or reacting negatively.

With a deep breath, he carefully walked backward and moved the rune away from the stand.

He sighed in relief, knowing he had succeeded without causing any reactions at all.

"I did it," he muttered to himself, feeling a sense of accomplishment wash over him.

'But it's not over yet. Now for the real deal,' he thought.

He needed to be quick for this to succeed.

Once everything was in place, he gripped the rune and removed the electricity from his hands.

Clasping the rune tightly, he heard a notification from the system.

[System: Do you wish to absorb the rune?]

"Yes!" he hurriedly replied.

CRACK!

The runes shattered into pieces, and the energy coursed through him, immediately redirecting to his cores where the other runes were embedded.

He felt his body growing heavier, not just a feeling—his feet was literally sinking to the ground.

'What's happening?'.

The pressure increased, making it hard to move. It felt like gravity itself was pulling him down, trying to crush him.

[System: Rune absorption in progress. The rune's energy is integrating with your body.]

"Alright," he replied casually.

The increase in pressure was not problematic for him, considering how powerful his body was.

But as time passed, he felt that the integration was having an adverse effect.

It reminded him of what had happened to Jayden, or Arc as he was now known, when he had forcibly destroyed the rune to gain a boost in power.

The only difference was that, because he was a demon made of hard material, the internal pressure wasn't as severe.

Instead, he felt his body getting progressively heavier.

[System: Integration 50% complete.]

He started sinking more to the ground, but he didn't do anything at all; this was nothing compared to being melted into literal molten metal.

That experience raised his threshold for pain to an extreme level; he doubted anything could surpass the sensation of slowly melting down into liquid, only to be reformed again.

[System: Integration 65% complete.]

[System: Integration 75% complete.]

He continued sinking, now almost neck-deep in the ground.

[System: Integration 85% complete.]

Then, just as he thought he would be buried alive, the pressure began to ease up.

[System: Integration 100% complete. Rune successfully absorbed. New Rune unlocked: Overweight.]

"Overweight, huh? Why do I feel like this rune's name is a bit insulting?" he pondered aloud, a wry smile tugging at his lips.

He started reading the description and formed a general idea of what it means.

'Alright, let's test it,' he muttered, eager to try out his new ability.

He started by using his hand to climb out of the hole first.

Next, he started thinking of the best and easiest way to check how effective it was in a real battle.

'I think that will work'

He summoned his Skull Grinder, the chainsaw-like sword that now looked sleeker and thinner after his evolution into an Overlord. Its blade shimmered with red hue.

R-R-R-R-R-R!

The weapon hummed to life, its cutting-teeth spinning menacingly.

Raising it high, he focused on increasing its mass as he brought it down.

The moment the blade began its descent, he felt the difference.

The force behind the slash doubled in an instant, and the ground where the sword struck split open, a deep gash carved into the floor.

"This rune is incredible," he chuckled aloud, his fingers tapping eagerly on the surface of the weapon.

The increased mass added so much power to his swing that it felt like an entirely new weapon.

'Let see…'

He lifted the Skull Grinder again, feeling its weight return to normal.

'So I can only increase the weight but not lower it down than its original one,' he thought to himself, discovering the limitations of the rune.

If the rune could also decrease weight, its effect would be more useful .

He decided to further test its capabilities to see just how much he could increase the weight of his attacks.

He swung the Skull Grinder again, focusing on increasing its mass.

With each swing, the weight increased by a notch, pushing the limits of the rune's power.

The force behind each blow was getting stronger, causing deep fissures in the ground and sending shock-waves through the air.

After a series of swings, he reached his maximum of seven times the original .

'Seven times the weight,' he muttered, impressed by the rune's capacity. 'That's not bad at all' he nodded in satisfaction.

It meant that if he was wielding a 100kg weapon, he could enhance its weight with each swing until it reached a staggering 700kg.

This increase was separate from the actual force he applied to his swings, which meant that the actual impact force would be much stronger if timed perfectly.

The reason was in the physics of mass and acceleration.

It was akin to dropping a heavy ball of metal versus dropping a wood at the same height.

Despite applying the same force to both objects, the heavier one would accelerate faster due to its greater mass.

And the greater the acceleration, the more damage it could cause.

'I'll try testing it on my other skills later,' he mentally noted, planning to further experiment with this new ability.

As he reabsorbed the Skull Grinder, he began to ponder the strength and abilities of Satoshi, the creator of the runes.

For someone to craft an object capable of altering the natural laws of the world, Satoshi must have been extraordinarily powerful.

'Just how strong was hei?' he wondered. 'To create runes that can manipulate mass… its even more complex than the elemental runes'

He considered the potential of the rune he had just absorbed.

While elemental runes granted him control over specific elements, this new rune offered a broader range of applications.

Increasing the mass of his attacks, enhancing his physical strength, and even creating defensive measures were just a few of the possibilities.

He knew he had only scratched the surface of its potential. The ability to manipulate mass could change the way he fought.

"I wonder if someday, I could also create things like this," he wondered aloud, contemplating the rune's intricate design and its creator's skill.

Right now, all of his original skills still followed the laws of nature and physics, but the runes, on the other hand, did not.

They were more magical than scientific, if he was being honest.

Even the defense mechanism that he encountered before was something that could not be explained by science or logic.

"Speaking of magic…" He turned towards the stand, thinking there might be still something there that could be useful to him.

He walked closer to study it more closely.