Aku felt the adrenaline running through his body, and as it did, an idea occurred to him.
Strengthening every cell and muscle fiber, tendon and bone within his body, but also manipulating them, to achieve more efficiency.
To propel himself, Aku didn't just bend his knees. He contracted every muscle in his legs and then shot forward at an inhuman speed.
The speed he reached was incredible. If not for his superior cognition he wouldn't even have been able to react in time to attack.
He spun his body while his fist, which had also been tensed to begin storing mechanical energy, released all that force.
His arm didn't just transmit the explosive force of his muscles, but also channeled the acceleration of his body and all his weight into a single blow.
The power was monstrous, enough to make the air roar in a brutal shockwave.
Bīng Xuě shot backward with excessive acceleration yet there wasn't a single scratch on his body.
But Aku knew why. He had noticed it upon striking.
Now that he had devoured the curses in his body, he was more familiar with negative spiritual energy, and he could detect how it was acting on Bīng Xuě's body, erasing the damage.
"Now I understand. It's not that you're invulnerable. There's something nullifying the damage in your body, am I wrong?" Aku asked, though deep down he knew he wasn't.
Bīng Xuě smiled. His secret had been discovered.
He, unlike other heroes who had fallen due to their lack of power, had lost due to his lack of will.
Or perhaps his selfishness.
That's why, when the demon queen of his world proposed a deal, he couldn't refuse.
Acquiring cursed powers.
The power of curses.
"So you noticed... well, I suppose there's no reason to hide it anymore. I'll have to go all out," Bīng Xuě said as the aura he was emanating became more ominous.
Suddenly, the veins of his body turned purple, his nails grew, his eyes turned purple, and two long horns grew from his head.
Aku prepared for battle, positioning himself at a half profile with his knees slightly bent and his feet shoulder-width apart.
Meanwhile, Bīng Xuě created a katana of purple ice in one of his hands.
"[Steps of the Dark Mist]," Bīng Xuě announced as his hair came loose and he disappeared, reappearing in front of Aku.
Bīng Xuě's katana descended at high speed while a purple aura surrounded it.
All the damage accumulated by the curse had been expelled and materialized in the form of that aura.
That meant that cut carried the power of every blow he had received.
Aku stepped back, but didn't react in time, and his arm was cut.
His armor was of no use either, as it was cut through too.
Aku however acted fast. His nervous system shot out from the wound and rejoined his arm, then brought both parts back together.
"Heh, that won't work for you anymore. Healing is [Taboo]!" Bīng Xuě exclaimed with a smile as he made another cut toward the demon king's shoulder.
Aku didn't back away. On the contrary, he took the cut head on, but at the same time he twisted his hip and sent a powerful attack at Bīng Xuě.
A punch with his full weight, though it had something special about it.
It was a thermal punch. Aku had transformed the negative spiritual energy into azoth, and with it had generated a small zone of {advanced chaos} around his fist.
This area greatly increased the disorder of the particles, making them more chaotic and therefore raising their energy.
His punch impacted against Bīng Xuě with tremendous force. Every muscle in Aku's arm had unleashed an incredible force channeled into his face.
But there was also the thermal effect that made it a far more lethal blow.
Bīng Xuě's neck twisted as he was sent flying to the side.
Bīng Xuě bounced several times across the ground until his body was stopped by some trees.
However, the hero smiled.
"Ha! Idiot. You sacrificed half your body to land an attack that did nothing to me! Looks like I win, hahahaha!" the young man laughed, still on the ground.
It was true. Bīng Xuě had managed to land a clean cut, slicing Aku diagonally in half.
"Are you sure about that?" the demon king responded, looking at Bīng Xuě with a calm expression.
He was unharmed.
"Huh? How?" Bīng Xuě said confused, trying to get up, but the dizziness brought him back to the ground.
Why was he dizzy?
"Isn't it obvious? When you attacked I simply displaced every cell of my body so they wouldn't come into contact with your blade's edge. It's not that you cut my body, I simply moved the matter aside," the demon king explained calmly. "By the way, are you sure you can say my blow was useless?"
Bīng Xuě raised an eyebrow. What was he talking about?
However, it was true that he could no longer feel one side of his face.
Carefully the boy touched his face, noticing that the side that had taken the blow felt strange.
"What... how?" Scared for the first time in the fight, Bīng Xuě created a piece of ice in his hand to see his own reflection.
Seeing the state of his face, he was stunned.
Half his face was burned, even his eye was damaged, though only when he noticed did he realize he had lost vision in it.
"I... I've been hurt?"
Bīng Xuě was incredulous. He who had been invulnerable since accepting the deal with the demon queen had been damaged.
What kind of monster was he facing?