The stone door silently closed behind them.
The foul stench was instantly cut off, replaced by an even more pungent smell—the sweetness of rotting flesh mixed with disinfectant, along with the scorched odor unique to certain chakra solutions, like burned metal.
Hyuga Xiao had long since activated his Byakugan.
His vision pierced through the darkness, revealing the full layout of the third level.
This was a more orderly space than the Breeding Farm on the second level, roughly half the size of a training ground. The walls were no longer rough stone, but covered in some grayish-white synthetic material, its surface flowing with pale blue chakra circuit patterns. A fist-sized illumination stone was embedded in the ceiling every five meters, giving off a ghastly white light.
But what truly made Xiao's pupils contract was the thing in the center of the room.
It was a massive transparent cultivation tank more than three meters in diameter, filled with a thick, dark green liquid. Soaking within it was a constantly writhing, tumor-like mass of flesh, its surface covered in vein-like bulges, as well as—
Dozens of eyeballs.
Byakugan.
Every one of them remained activated. Their pale bluish-white pupils slowly rotated across the tumor's surface like eerie gemstones embedded in a monster. The tumor itself had no fixed shape, swelling and contracting at times. Every wriggle squeezed the surrounding liquid and produced a dull, bubbling gurgle.
"This is..." Clone Shisui's voice sounded from behind Xiao, carrying obvious shock. "Danzo's Laboratory records mentioned it before... the Byakugan Aggregate experiment. The Main House had always been trying to fuse the power of multiple Byakugan and create humanoid weapons that could be mass-produced. But every test subject collapsed because of chakra conflicts."
Xiao said nothing.
His gaze was fixed on one eyeball on the tumor's surface.