...The nine hundred and ninety-ninth floor!
Green stopped on the final step.
He glanced around. The farther he went, the wider the corridor became. By now, it was as broad as a sports field, and he had to walk several hundred meters to reach the next step.
"Going by the pattern of increasing strength, the creature on the 1,000th floor is probably a Fourth-Level Lifeform!" A hint of delight flickered in Green's eyes.
The Rule progress bar in the interface at the lower right of his vision had reached 12%.
"Secondary Lifeforms have undergone a qualitative transformation. By the usual pattern, this time I should be able to push the Rule progress past 20%!"
With that thought, Green stepped onto the 1,000th-floor platform without hesitation.
Creak!
The moment he set foot on the platform, a creaking sound came from the gray stone wall at the edge of the black spiral staircase. A door appeared in the wall.
As Green stepped onto the 1,000th floor, the door opened partway by itself. Blue light spilled from within, bright enough to overpower the candlelight mounted on the wall.
Instead of the monster he had expected, a door had appeared—and there seemed to be something inside.
"There definitely wasn't a door just now. It only appeared when I stepped onto the 1,000th-floor platform!"
Green slowly approached the door, his mental guard raised to the highest level.
"My Mental Power can't penetrate it?" As he drew closer, Green frowned.
The door in front of him seemed to block all perception. Neither Mental Power nor Soul Power could pass through it.
"But luckily, I'm a Wizard, not a warrior. I don't need to put myself in danger!"
As he spoke, he cast a spell.
Blue and black mist suddenly appeared in the air. The two kinds