The senses weren't the only thing he sacrificed...
In the past month, Grey had become a battle-hungry menace. He fought monster after monster, day and night.
There were no F-rank monsters in the forest. So, he mainly hunted E-rank, D-rank, and occasionally C-rank creatures. During that time, he ran countless experiments—sacrificing not just his senses, but his emotions, his limbs… even four hours of his lifespan, all just to test the limits of the rune.
And the results surprised him.
Emotions were the easiest to give up. The stronger the emotion he felt toward someone, the greater the fire the rune could produce. He discovered that the safest sacrifice was, indeed, emotion. But there was a limit. With emotion alone, the rune could only generate enough power to match E-rank threats. If he sacrificed all emotion, he could face off against a D-rank hunter.
But a D-rank monster? That was a different story.
Monsters were built for battle. Their skin was tougher than steel, their bodies like living weapons. Even Elsa had told him: it usually takes three to five D-rank hunters to take down a peak D-rank monster.
As for C-ranks? Grey stood no chance without offering something more—his body, or his time.
In the last month, he had fought two C-rank monsters. One of those times, Elsa had to step in to save him. The second time, he was forced to sacrifice his leg, all his emotions, and every one of his senses for an entire day.
That battle left him feeling truly powerless.
This was the troubling part. The rune did grant him power, but it was temporary. Against a group of enemies attacking one by one, Grey would lose. But if they all came at him at once? He could wipe them out in a single burst.
That was his first major drawback.
The second drawback was even worse.
Without using the rune, Grey was like an ordinary person. Powerless. Even an F-rank could beat the hell out of him.
He once told Elsa that, back in the village before entering the forest, he had fought a so-called D-rank thug and defeated him without using the rune.
Elsa had laughed so hard she doubled over, clutching her stomach.
"That wasn't a D-rank, you idiot. That was an F-rank! If you fought a real D-rank back then, you'd be dead!"
Grey didn't argue. Her explanation seemed reasonable. Compared to the E-rank monsters he had fought, that thug had been far weaker.
Elsa also explained something else—something important.
Unlike him, hunters could learn skills. She even showed him a few scrolls, calling them "Skill Scrolls." If she tore one open, she'd gain a new ability instantly.
"..."
Grey stared at her in silence,
She was a really a walking treasure trove.