Growth

Both of them were exhausted from the given circumstance before ascending to the next floor. Getting stronger in a short time was the appropriate thing to do. Why? Because they never knew what kind of opponents they were going to face sooner or later.

Yet, not all the adventurers would have the same opportunity. The thing here was, that Kai had the skill to grow in just the blink of an eye, which was absorbing the monster's ability by eating the core. The only downside, using this skill could easily take his life, especially, the cores from the high-level monsters.

To elaborate it, he had [Core manifestation], [Appraisal] skill that allowed him to have extra comrades, especially, the gaming interface that allowed him to increase his stats, at the same time, bestowed different skills.

As of now, he had skills that came from different skills like, [Stealth] skill came from rogue, [Strike] (swordsman), [Deadly reach] (Lancer), and [Appraisal] skill (Necromancer).