Shinobi World No. 1.
Konoha Year 43, autumn.
Deep within Sandcastle Base, on the border of the Land of Wind.
This place appeared on no known map and lay beyond the reach of any perception. Thick layers of rock, dense Sealing Runes, and the distorted force field of the Dragon Vein Great Formation completely isolated this underground space from the outside world. Even the Sage of Six Paths' Rinnegan could not penetrate these layers of barriers.
Toyotomi Yinglang stood at the center of a massive formation nexus built from dark-gold Dragon Vein crystals, a pale golden halo of energy surrounding him. His gaze rested on the "mountain" slowly taking shape before him.
It was no ordinary mountain.
It stood roughly a hundred meters tall, pitch-black throughout, its surface covered in dense, dark-red patterns resembling blood vessels. Those patterns pulsed slowly, as though the mountain were alive-it was breathing. Within the mountain, countless tiny points of light could faintly be seen, flickering like stars in the darkness. Those lights were the nascent forms of "Soul Yin Stones."
Soul Yin Mountain.
Toyotomi Yinglang had spent three years "creating" this mountain, combining the Forbidden Technique: Emotion Transformation, Dragon Vein power, the Evil God's faith feedback mechanism, and various fragments of knowledge obtained from the system's lottery.
Its workings were convoluted to explain, but the core was simple:
Convert emotions into spiritual energy, then solidify that spiritual energy into absorbable "ore."
The Forbidden Technique: Emotion Transformation originally could only convert its user's negative emotions into a temporary power boost, with severe side effects and no lasting effect. Toyotomi Yinglang had extracted and reconstructed its core principles. Combining the Dragon Vein power's fine control over energy with the cycle in the Evil God's faith system-"believers provide emotions → the Evil God converts them → evil